what is an abstract in a research work

Writing an Abstract for Your Research Paper

Definition and Purpose of Abstracts

An abstract is a short summary of your (published or unpublished) research paper, usually about a paragraph (c. 6-7 sentences, 150-250 words) long. A well-written abstract serves multiple purposes:

• an abstract lets readers get the gist or essence of your paper or article quickly, in order to decide whether to read the full paper;
• an abstract prepares readers to follow the detailed information, analyses, and arguments in your full paper;
• and, later, an abstract helps readers remember key points from your paper.

It’s also worth remembering that search engines and bibliographic databases use abstracts, as well as the title, to identify key terms for indexing your published paper. So what you include in your abstract and in your title are crucial for helping other researchers find your paper or article.

If you are writing an abstract for a course paper, your professor may give you specific guidelines for what to include and how to organize your abstract. Similarly, academic journals often have specific requirements for abstracts. So in addition to following the advice on this page, you should be sure to look for and follow any guidelines from the course or journal you’re writing for.

The Contents of an Abstract

Abstracts contain most of the following kinds of information in brief form. The body of your paper will, of course, develop and explain these ideas much more fully. As you will see in the samples below, the proportion of your abstract that you devote to each kind of information—and the sequence of that information—will vary, depending on the nature and genre of the paper that you are summarizing in your abstract. And in some cases, some of this information is implied, rather than stated explicitly. The Publication Manual of the American Psychological Association , which is widely used in the social sciences, gives specific guidelines for what to include in the abstract for different kinds of papers—for empirical studies, literature reviews or meta-analyses, theoretical papers, methodological papers, and case studies.

Here are the typical kinds of information found in most abstracts:

• the context or background information for your research; the general topic under study; the specific topic of your research
• the central questions or statement of the problem your research addresses
• what’s already known about this question, what previous research has done or shown
• the main reason(s) , the exigency, the rationale , the goals for your research—Why is it important to address these questions? Are you, for example, examining a new topic? Why is that topic worth examining? Are you filling a gap in previous research? Applying new methods to take a fresh look at existing ideas or data? Resolving a dispute within the literature in your field? . . .
• your research and/or analytical methods
• your main findings , results , or arguments
• the significance or implications of your findings or arguments.

Your abstract should be intelligible on its own, without a reader’s having to read your entire paper. And in an abstract, you usually do not cite references—most of your abstract will describe what you have studied in your research and what you have found and what you argue in your paper. In the body of your paper, you will cite the specific literature that informs your research.

When to Write Your Abstract

Although you might be tempted to write your abstract first because it will appear as the very first part of your paper, it’s a good idea to wait to write your abstract until after you’ve drafted your full paper, so that you know what you’re summarizing.

What follows are some sample abstracts in published papers or articles, all written by faculty at UW-Madison who come from a variety of disciplines. We have annotated these samples to help you see the work that these authors are doing within their abstracts.

Choosing Verb Tenses within Your Abstract

The social science sample (Sample 1) below uses the present tense to describe general facts and interpretations that have been and are currently true, including the prevailing explanation for the social phenomenon under study. That abstract also uses the present tense to describe the methods, the findings, the arguments, and the implications of the findings from their new research study. The authors use the past tense to describe previous research.

The humanities sample (Sample 2) below uses the past tense to describe completed events in the past (the texts created in the pulp fiction industry in the 1970s and 80s) and uses the present tense to describe what is happening in those texts, to explain the significance or meaning of those texts, and to describe the arguments presented in the article.

The science samples (Samples 3 and 4) below use the past tense to describe what previous research studies have done and the research the authors have conducted, the methods they have followed, and what they have found. In their rationale or justification for their research (what remains to be done), they use the present tense. They also use the present tense to introduce their study (in Sample 3, “Here we report . . .”) and to explain the significance of their study (In Sample 3, This reprogramming . . . “provides a scalable cell source for. . .”).

Sample Abstract 1

From the social sciences.

Reporting new findings about the reasons for increasing economic homogamy among spouses

Gonalons-Pons, Pilar, and Christine R. Schwartz. “Trends in Economic Homogamy: Changes in Assortative Mating or the Division of Labor in Marriage?” Demography , vol. 54, no. 3, 2017, pp. 985-1005.

Sample Abstract 2

From the humanities.

Analyzing underground pulp fiction publications in Tanzania, this article makes an argument about the cultural significance of those publications

Emily Callaci. “Street Textuality: Socialism, Masculinity, and Urban Belonging in Tanzania’s Pulp Fiction Publishing Industry, 1975-1985.” Comparative Studies in Society and History , vol. 59, no. 1, 2017, pp. 183-210.

Sample Abstract/Summary 3

From the sciences.

Reporting a new method for reprogramming adult mouse fibroblasts into induced cardiac progenitor cells

Lalit, Pratik A., Max R. Salick, Daryl O. Nelson, Jayne M. Squirrell, Christina M. Shafer, Neel G. Patel, Imaan Saeed, Eric G. Schmuck, Yogananda S. Markandeya, Rachel Wong, Martin R. Lea, Kevin W. Eliceiri, Timothy A. Hacker, Wendy C. Crone, Michael Kyba, Daniel J. Garry, Ron Stewart, James A. Thomson, Karen M. Downs, Gary E. Lyons, and Timothy J. Kamp. “Lineage Reprogramming of Fibroblasts into Proliferative Induced Cardiac Progenitor Cells by Defined Factors.” Cell Stem Cell , vol. 18, 2016, pp. 354-367.

Sample Abstract 4, a Structured Abstract

Reporting results about the effectiveness of antibiotic therapy in managing acute bacterial sinusitis, from a rigorously controlled study

Note: This journal requires authors to organize their abstract into four specific sections, with strict word limits. Because the headings for this structured abstract are self-explanatory, we have chosen not to add annotations to this sample abstract.

Wald, Ellen R., David Nash, and Jens Eickhoff. “Effectiveness of Amoxicillin/Clavulanate Potassium in the Treatment of Acute Bacterial Sinusitis in Children.” Pediatrics , vol. 124, no. 1, 2009, pp. 9-15.

“OBJECTIVE: The role of antibiotic therapy in managing acute bacterial sinusitis (ABS) in children is controversial. The purpose of this study was to determine the effectiveness of high-dose amoxicillin/potassium clavulanate in the treatment of children diagnosed with ABS.

METHODS : This was a randomized, double-blind, placebo-controlled study. Children 1 to 10 years of age with a clinical presentation compatible with ABS were eligible for participation. Patients were stratified according to age (<6 or ≥6 years) and clinical severity and randomly assigned to receive either amoxicillin (90 mg/kg) with potassium clavulanate (6.4 mg/kg) or placebo. A symptom survey was performed on days 0, 1, 2, 3, 5, 7, 10, 20, and 30. Patients were examined on day 14. Children’s conditions were rated as cured, improved, or failed according to scoring rules.

RESULTS: Two thousand one hundred thirty-five children with respiratory complaints were screened for enrollment; 139 (6.5%) had ABS. Fifty-eight patients were enrolled, and 56 were randomly assigned. The mean age was 6630 months. Fifty (89%) patients presented with persistent symptoms, and 6 (11%) presented with nonpersistent symptoms. In 24 (43%) children, the illness was classified as mild, whereas in the remaining 32 (57%) children it was severe. Of the 28 children who received the antibiotic, 14 (50%) were cured, 4 (14%) were improved, 4(14%) experienced treatment failure, and 6 (21%) withdrew. Of the 28children who received placebo, 4 (14%) were cured, 5 (18%) improved, and 19 (68%) experienced treatment failure. Children receiving the antibiotic were more likely to be cured (50% vs 14%) and less likely to have treatment failure (14% vs 68%) than children receiving the placebo.

CONCLUSIONS : ABS is a common complication of viral upper respiratory infections. Amoxicillin/potassium clavulanate results in significantly more cures and fewer failures than placebo, according to parental report of time to resolution.” (9)

Some Excellent Advice about Writing Abstracts for Basic Science Research Papers, by Professor Adriano Aguzzi from the Institute of Neuropathology at the University of Zurich:

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Organizing Your Social Sciences Research Paper

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An abstract summarizes, usually in one paragraph of 300 words or less, the major aspects of the entire paper in a prescribed sequence that includes: 1) the overall purpose of the study and the research problem(s) you investigated; 2) the basic design of the study; 3) major findings or trends found as a result of your analysis; and, 4) a brief summary of your interpretations and conclusions.

Writing an Abstract. The Writing Center. Clarion University, 2009; Writing an Abstract for Your Research Paper. The Writing Center, University of Wisconsin, Madison; Koltay, Tibor. Abstracts and Abstracting: A Genre and Set of Skills for the Twenty-first Century . Oxford, UK: Chandos Publishing, 2010;

Importance of a Good Abstract

Sometimes your professor will ask you to include an abstract, or general summary of your work, with your research paper. The abstract allows you to elaborate upon each major aspect of the paper and helps readers decide whether they want to read the rest of the paper. Therefore, enough key information [e.g., summary results, observations, trends, etc.] must be included to make the abstract useful to someone who may want to examine your work.

How do you know when you have enough information in your abstract? A simple rule-of-thumb is to imagine that you are another researcher doing a similar study. Then ask yourself: if your abstract was the only part of the paper you could access, would you be happy with the amount of information presented there? Does it tell the whole story about your study? If the answer is "no" then the abstract likely needs to be revised.

Farkas, David K. “A Scheme for Understanding and Writing Summaries.” Technical Communication 67 (August 2020): 45-60;  How to Write a Research Abstract. Office of Undergraduate Research. University of Kentucky; Staiger, David L. “What Today’s Students Need to Know about Writing Abstracts.” International Journal of Business Communication January 3 (1966): 29-33; Swales, John M. and Christine B. Feak. Abstracts and the Writing of Abstracts . Ann Arbor, MI: University of Michigan Press, 2009.

Structure and Writing Style

I.  Types of Abstracts

To begin, you need to determine which type of abstract you should include with your paper. There are four general types.

Critical Abstract A critical abstract provides, in addition to describing main findings and information, a judgment or comment about the study’s validity, reliability, or completeness. The researcher evaluates the paper and often compares it with other works on the same subject. Critical abstracts are generally 400-500 words in length due to the additional interpretive commentary. These types of abstracts are used infrequently.

Descriptive Abstract A descriptive abstract indicates the type of information found in the work. It makes no judgments about the work, nor does it provide results or conclusions of the research. It does incorporate key words found in the text and may include the purpose, methods, and scope of the research. Essentially, the descriptive abstract only describes the work being summarized. Some researchers consider it an outline of the work, rather than a summary. Descriptive abstracts are usually very short, 100 words or less. Informative Abstract The majority of abstracts are informative. While they still do not critique or evaluate a work, they do more than describe it. A good informative abstract acts as a surrogate for the work itself. That is, the researcher presents and explains all the main arguments and the important results and evidence in the paper. An informative abstract includes the information that can be found in a descriptive abstract [purpose, methods, scope] but it also includes the results and conclusions of the research and the recommendations of the author. The length varies according to discipline, but an informative abstract is usually no more than 300 words in length.

Highlight Abstract A highlight abstract is specifically written to attract the reader’s attention to the study. No pretense is made of there being either a balanced or complete picture of the paper and, in fact, incomplete and leading remarks may be used to spark the reader’s interest. In that a highlight abstract cannot stand independent of its associated article, it is not a true abstract and, therefore, rarely used in academic writing.

II.  Writing Style

Use the active voice when possible , but note that much of your abstract may require passive sentence constructions. Regardless, write your abstract using concise, but complete, sentences. Get to the point quickly and always use the past tense because you are reporting on a study that has been completed.

Abstracts should be formatted as a single paragraph in a block format and with no paragraph indentations. In most cases, the abstract page immediately follows the title page. Do not number the page. Rules set forth in writing manual vary but, in general, you should center the word "Abstract" at the top of the page with double spacing between the heading and the abstract. The final sentences of an abstract concisely summarize your study’s conclusions, implications, or applications to practice and, if appropriate, can be followed by a statement about the need for additional research revealed from the findings.

Composing Your Abstract

Although it is the first section of your paper, the abstract should be written last since it will summarize the contents of your entire paper. A good strategy to begin composing your abstract is to take whole sentences or key phrases from each section of the paper and put them in a sequence that summarizes the contents. Then revise or add phrases or words to make the narrative flow clearly and smoothly. A useful strategy is to avoid using conjunctions [ e.g. and, but, if] that connect long clauses or sentences and, instead, write short, concise sentences . Note that statistical findings should be reported parenthetically [i.e., written in parentheses].

Before handing in your final paper, check to make sure that the information in the abstract completely agrees with what you have written in the paper. Think of the abstract as a sequential set of complete sentences describing the most crucial information using the fewest necessary words. The abstract SHOULD NOT contain:

• A catchy introductory phrase, provocative quote, or other device to grab the reader's attention,
• Lengthy background or contextual information,
• Redundant phrases, unnecessary adverbs and adjectives, and repetitive information;
• Acronyms or abbreviations,
• References to other literature [say something like, "current research shows that..." or "studies have indicated..."],
• Using ellipticals [i.e., ending with "..."] or incomplete sentences,
• Jargon or terms that may be confusing to the reader,
• Citations to other works, and
• Any sort of image, illustration, figure, or table, or references to them.

Abstract. Writing Center. University of Kansas; Abstract. The Structure, Format, Content, and Style of a Journal-Style Scientific Paper. Department of Biology. Bates College; Abstracts. The Writing Center. University of North Carolina; Borko, Harold and Seymour Chatman. "Criteria for Acceptable Abstracts: A Survey of Abstracters' Instructions." American Documentation 14 (April 1963): 149-160; Abstracts. The Writer’s Handbook. Writing Center. University of Wisconsin, Madison; Hartley, James and Lucy Betts. "Common Weaknesses in Traditional Abstracts in the Social Sciences." Journal of the American Society for Information Science and Technology 60 (October 2009): 2010-2018; Koltay, Tibor. Abstracts and Abstracting: A Genre and Set of Skills for the Twenty-first Century. Oxford, UK: Chandos Publishing, 2010; Procter, Margaret. The Abstract. University College Writing Centre. University of Toronto; Riordan, Laura. “Mastering the Art of Abstracts.” The Journal of the American Osteopathic Association 115 (January 2015 ): 41-47; Writing Report Abstracts. The Writing Lab and The OWL. Purdue University; Writing Abstracts. Writing Tutorial Services, Center for Innovative Teaching and Learning. Indiana University; Koltay, Tibor. Abstracts and Abstracting: A Genre and Set of Skills for the Twenty-First Century . Oxford, UK: 2010; Writing an Abstract for Your Research Paper. The Writing Center, University of Wisconsin, Madison.

Writing Tip

Never Cite Just the Abstract!

Citing to just a journal article's abstract does not confirm for the reader that you have conducted a thorough or reliable review of the literature. If the full-text is not available, go to the USC Libraries main page and enter the title of the article [NOT the title of the journal]. If the Libraries have a subscription to the journal, the article should appear with a link to the full-text or to the journal publisher page where you can get the article. If the article does not appear, try searching Google Scholar using the link on the USC Libraries main page [scroll down under the heading Quick Links]. If you still can't find the article after doing this, contact a librarian or you can request it from our free i nterlibrary loan and document delivery service .

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How to Write an Abstract (With Examples)

By Sarah Oakley

Table of Contents

What is an abstract in a paper, how long should an abstract be, 5 steps for writing an abstract, examples of an abstract, how prowritingaid can help you write an abstract.

If you are writing a scientific research paper or a book proposal, you need to know how to write an abstract, which summarizes the contents of the paper or book.

When researchers are looking for peer-reviewed papers to use in their studies, the first place they will check is the abstract to see if it applies to their work. Therefore, your abstract is one of the most important parts of your entire paper.

In this article, we’ll explain what an abstract is, what it should include, and how to write one.

An abstract is a concise summary of the details within a report. Some abstracts give more details than others, but the main things you’ll be talking about are why you conducted the research, what you did, and what the results show.

When a reader is deciding whether to read your paper completely, they will first look at the abstract. You need to be concise in your abstract and give the reader the most important information so they can determine if they want to read the whole paper.

Remember that an abstract is the last thing you’ll want to write for the research paper because it directly references parts of the report. If you haven’t written the report, you won’t know what to include in your abstract.

If you are writing a paper for a journal or an assignment, the publication or academic institution might have specific formatting rules for how long your abstract should be. However, if they don’t, most abstracts are between 150 and 300 words long.

A short word count means your writing has to be precise and without filler words or phrases. Once you’ve written a first draft, you can always use an editing tool, such as ProWritingAid, to identify areas where you can reduce words and increase readability.

If your abstract is over the word limit, and you’ve edited it but still can’t figure out how to reduce it further, your abstract might include some things that aren’t needed. Here’s a list of three elements you can remove from your abstract:

Discussion : You don’t need to go into detail about the findings of your research because your reader will find your discussion within the paper.

Definition of terms : Your readers are interested the field you are writing about, so they are likely to understand the terms you are using. If not, they can always look them up. Your readers do not expect you to give a definition of terms in your abstract.

References and citations : You can mention there have been studies that support or have inspired your research, but you do not need to give details as the reader will find them in your bibliography.

Good writing = better grades

ProWritingAid will help you improve the style, strength, and clarity of all your assignments.

If you’ve never written an abstract before, and you’re wondering how to write an abstract, we’ve got some steps for you to follow. It’s best to start with planning your abstract, so we’ve outlined the details you need to include in your plan before you write.

Remember to consider your audience when you’re planning and writing your abstract. They are likely to skim read your abstract, so you want to be sure your abstract delivers all the information they’re expecting to see at key points.

1. What Should an Abstract Include?

Abstracts have a lot of information to cover in a short number of words, so it’s important to know what to include. There are three elements that need to be present in your abstract:

Your context is the background for where your research sits within your field of study. You should briefly mention any previous scientific papers or experiments that have led to your hypothesis and how research develops in those studies.

Your hypothesis is your prediction of what your study will show. As you are writing your abstract after you have conducted your research, you should still include your hypothesis in your abstract because it shows the motivation for your paper.

Throughout your abstract, you also need to include keywords and phrases that will help researchers to find your article in the databases they’re searching. Make sure the keywords are specific to your field of study and the subject you’re reporting on, otherwise your article might not reach the relevant audience.

2. Can You Use First Person in an Abstract?

You might think that first person is too informal for a research paper, but it’s not. Historically, writers of academic reports avoided writing in first person to uphold the formality standards of the time. However, first person is more accepted in research papers in modern times.

If you’re still unsure whether to write in first person for your abstract, refer to any style guide rules imposed by the journal you’re writing for or your teachers if you are writing an assignment.

3. Abstract Structure

Some scientific journals have strict rules on how to structure an abstract, so it’s best to check those first. If you don’t have any style rules to follow, try using the IMRaD structure, which stands for Introduction, Methodology, Results, and Discussion.

Following the IMRaD structure, start with an introduction. The amount of background information you should include depends on your specific research area. Adding a broad overview gives you less room to include other details. Remember to include your hypothesis in this section.

The next part of your abstract should cover your methodology. Try to include the following details if they apply to your study:

What type of research was conducted?

How were the test subjects sampled?

What were the sample sizes?

What was done to each group?

How long was the experiment?

How was data recorded and interpreted?

Following the methodology, include a sentence or two about the results, which is where your reader will determine if your research supports or contradicts their own investigations.

The results are also where most people will want to find out what your outcomes were, even if they are just mildly interested in your research area. You should be specific about all the details but as concise as possible.

The last few sentences are your conclusion. It needs to explain how your findings affect the context and whether your hypothesis was correct. Include the primary take-home message, additional findings of importance, and perspective. Also explain whether there is scope for further research into the subject of your report.

Your conclusion should be honest and give the reader the ultimate message that your research shows. Readers trust the conclusion, so make sure you’re not fabricating the results of your research. Some readers won’t read your entire paper, but this section will tell them if it’s worth them referencing it in their own study.

4. How to Start an Abstract

The first line of your abstract should give your reader the context of your report by providing background information. You can use this sentence to imply the motivation for your research.

You don’t need to use a hook phrase or device in your first sentence to grab the reader’s attention. Your reader will look to establish relevance quickly, so readability and clarity are more important than trying to persuade the reader to read on.

5. How to Format an Abstract

Most abstracts use the same formatting rules, which help the reader identify the abstract so they know where to look for it.

Here’s a list of formatting guidelines for writing an abstract:

Stick to one paragraph

Use block formatting with no indentation at the beginning

Put your abstract straight after the title and acknowledgements pages

Use present or past tense, not future tense

There are two primary types of abstract you could write for your paper—descriptive and informative.

An informative abstract is the most common, and they follow the structure mentioned previously. They are longer than descriptive abstracts because they cover more details.

Descriptive abstracts differ from informative abstracts, as they don’t include as much discussion or detail. The word count for a descriptive abstract is between 50 and 150 words.

Here is an example of an informative abstract:

A growing trend exists for authors to employ a more informal writing style that uses “we” in academic writing to acknowledge one’s stance and engagement. However, few studies have compared the ways in which the first-person pronoun “we” is used in the abstracts and conclusions of empirical papers. To address this lacuna in the literature, this study conducted a systematic corpus analysis of the use of “we” in the abstracts and conclusions of 400 articles collected from eight leading electrical and electronic (EE) engineering journals. The abstracts and conclusions were extracted to form two subcorpora, and an integrated framework was applied to analyze and seek to explain how we-clusters and we-collocations were employed. Results revealed whether authors’ use of first-person pronouns partially depends on a journal policy. The trend of using “we” showed that a yearly increase occurred in the frequency of “we” in EE journal papers, as well as the existence of three “we-use” types in the article conclusions and abstracts: exclusive, inclusive, and ambiguous. Other possible “we-use” alternatives such as “I” and other personal pronouns were used very rarely—if at all—in either section. These findings also suggest that the present tense was used more in article abstracts, but the present perfect tense was the most preferred tense in article conclusions. Both research and pedagogical implications are proffered and critically discussed.

Wang, S., Tseng, W.-T., & Johanson, R. (2021). To We or Not to We: Corpus-Based Research on First-Person Pronoun Use in Abstracts and Conclusions. SAGE Open, 11(2).

Here is an example of a descriptive abstract:

From the 1850s to the present, considerable criminological attention has focused on the development of theoretically-significant systems for classifying crime. This article reviews and attempts to evaluate a number of these efforts, and we conclude that further work on this basic task is needed. The latter part of the article explicates a conceptual foundation for a crime pattern classification system, and offers a preliminary taxonomy of crime.

Farr, K. A., & Gibbons, D. C. (1990). Observations on the Development of Crime Categories. International Journal of Offender Therapy and Comparative Criminology, 34(3), 223–237.

If you want to ensure your abstract is grammatically correct and easy to read, you can use ProWritingAid to edit it. The software integrates with Microsoft Word, Google Docs, and most web browsers, so you can make the most of it wherever you’re writing your paper.

Before you edit with ProWritingAid, make sure the suggestions you are seeing are relevant for your document by changing the document type to “Abstract” within the Academic writing style section.

You can use the Readability report to check your abstract for places to improve the clarity of your writing. Some suggestions might show you where to remove words, which is great if you’re over your word count.

We hope the five steps and examples we’ve provided help you write a great abstract for your research paper.

Sarah Oakley

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Expedite peer review, increase search-ability, and set the tone for your study

The abstract is your chance to let your readers know what they can expect from your article. Learn how to write a clear, and concise abstract that will keep your audience reading.

How your abstract impacts editorial evaluation and future readership

After the title , the abstract is the second-most-read part of your article. A good abstract can help to expedite peer review and, if your article is accepted for publication, it’s an important tool for readers to find and evaluate your work. Editors use your abstract when they first assess your article. Prospective reviewers see it when they decide whether to accept an invitation to review. Once published, the abstract gets indexed in PubMed and Google Scholar , as well as library systems and other popular databases. Like the title, your abstract influences keyword search results. Readers will use it to decide whether to read the rest of your article. Other researchers will use it to evaluate your work for inclusion in systematic reviews and meta-analysis. It should be a concise standalone piece that accurately represents your research. 

What to include in an abstract

The main challenge you’ll face when writing your abstract is keeping it concise AND fitting in all the information you need. Depending on your subject area the journal may require a structured abstract following specific headings. A structured abstract helps your readers understand your study more easily. If your journal doesn’t require a structured abstract it’s still a good idea to follow a similar format, just present the abstract as one paragraph without headings. 

Background or Introduction – What is currently known? Start with a brief, 2 or 3 sentence, introduction to the research area. 

Objectives or Aims – What is the study and why did you do it? Clearly state the research question you’re trying to answer.

Methods – What did you do? Explain what you did and how you did it. Include important information about your methods, but avoid the low-level specifics. Some disciplines have specific requirements for abstract methods. 

• CONSORT for randomized trials.
• STROBE for observational studies
• PRISMA for systematic reviews and meta-analyses

Results – What did you find? Briefly give the key findings of your study. Include key numeric data (including confidence intervals or p values), where possible.

Conclusions – What did you conclude? Tell the reader why your findings matter, and what this could mean for the ‘bigger picture’ of this area of research. 

Writing tips

The main challenge you may find when writing your abstract is keeping it concise AND convering all the information you need to.

• Keep it concise and to the point. Most journals have a maximum word count, so check guidelines before you write the abstract to save time editing it later.
• Write for your audience. Are they specialists in your specific field? Are they cross-disciplinary? Are they non-specialists? If you’re writing for a general audience, or your research could be of interest to the public keep your language as straightforward as possible. If you’re writing in English, do remember that not all of your readers will necessarily be native English speakers.
• Focus on key results, conclusions and take home messages.
• Write your paper first, then create the abstract as a summary.
• Check the journal requirements before you write your abstract, eg. required subheadings.
• Include keywords or phrases to help readers search for your work in indexing databases like PubMed or Google Scholar.
• Double and triple check your abstract for spelling and grammar errors. These kind of errors can give potential reviewers the impression that your research isn’t sound, and can make it easier to find reviewers who accept the invitation to review your manuscript. Your abstract should be a taste of what is to come in the rest of your article.

Don’t

• Sensationalize your research.
• Speculate about where this research might lead in the future.
• Use abbreviations or acronyms (unless absolutely necessary or unless they’re widely known, eg. DNA).
• Repeat yourself unnecessarily, eg. “Methods: We used X technique. Results: Using X technique, we found…”
• Contradict anything in the rest of your manuscript.
• Include content that isn’t also covered in the main manuscript.
• Include citations or references.

Tip: How to edit your work

Editing is challenging, especially if you are acting as both a writer and an editor. Read our guidelines for advice on how to refine your work, including useful tips for setting your intentions, re-review, and consultation with colleagues.

• How to Write a Great Title
• How to Write Your Methods
• How to Report Statistics
• How to Write Discussions and Conclusions
• How to Edit Your Work

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The contents of the Writing Center are also available as a live, interactive training session, complete with slides, talking points, and activities. …

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How To Write A Research Paper Abstract | Steps And Examples

Published by Alvin Nicolas at September 23rd, 2024 , Revised On October 24, 2024

An abstract is written to pique a reader’s interest and if necessary, motivate them to leave the comfort of their home and get the full article or paper.

In simpler words, an abstract is a well-structured summary of your academic work, such as an article, research paper , thesis or dissertation. It outlines the most important aspects of your work and is about 300-500 words. Although the structure may vary from discipline to discipline, it is still a necessary part of academic writing.

Abstract Research Paper Definition

A research paper abstract is the face of the research paper. This means that it is what creates the first impression of the paper. It is the summary of the research paper and communicates the content quality and relevance. They exist with one vital purpose, and that is to sell your research. A reader quickly scrutinises and scans the abstract to gain an idea of your research, the problem statement addressed, the methodologies used and the results gained from it.

An abstract most commonly has the following parts:

• Introduction

Types of Abstracts In Research Paper

One of the main purposes of an abstract is to describe your paper. It can either be informative, descriptive, structured or unstructured. Let’s develop a common understanding of how research paper abstracts are written based on content and writing style.

Structured Abstract

Structured abstracts are mostly written in journals and have a separate paragraph for each section. Each part is organised and has distinct headings such as introduction/background, objective, design, methodologies, material, results and conclusion.

Unstructured Abstract

An unstructured abstract is mostly used in social sciences and humanities disciplines and does not have separate paragraphs for each section. It consists of one whole paragraph that serves as the face of the research paper.

Descriptive Abstract

A descriptive abstract only outlines the crucial details of the researcher’s publication. They are mostly short, consisting of 75-105 words. They briefly explain the background, mission statement, purpose and objective but omit the research methodologies, results and conclusions.

Informative Abstract

This abstract can be both structured and unstructured and provides detailed information on the research paper. This means that it is an extensive paragraph on each aspect of research and provides accurate data on each section, especially results.

How to Make Abstract In Research Paper

The abstract part of the research paper summarises the main points of the article. Whether you are applying for research grants, writing a thesis or dissertation or studying a research problem , it is necessary to know how to make a good abstract for a research paper. Here are some of the details on how to write a research paper abstract.

General Topic In Study

This section serves as the introduction to the research paper. It answers the questions of what is being studied or what problem statement is being addressed here. The hypothesis and purpose are highlighted within this section, setting the context for the rest of the research paper.

It is recommended to never go into detailed information as this part only offers initial information regarding the research. Also, this part is always written in the present or past tense, and never in the future as the research has been completed.

Our study’s main objective was to assess the photoprotective capability of chocolate consumption, by contrasting a simple dark chocolate with a specifically made chocolate with preserved high flavanol. According to the study’s hypothesis, eating chocolate induced with HF can provide nutritional defence against skin damage by the sun.

Research/Analytical Methods

Next, it is important to write the research methods used in the research. Either qualitative or quantitative methods, every aspect of them should be mentioned to give the reader a good idea of what scale, survey and sample was used within the research. Some questions that need to be answered in this paragraph are:

• What was the research setting?
• What was the sample size, and how were the participants sampled?
• What was the research method used?
• What was the primary outcome of the initial test?
• What questions or treatments were administered to the participants?

A double-blinded in vivo study was carried out, where 30 healthy adults participated in it. It included 8 males and 22 females between the age of 10 years to 43 years. Fifteen subjects each were given either an HF or LF chocolate and were divided based on their skin phototypes.

Results/ Arguments

This section can be both in present and past tense and must include the main findings of the study. It should be detailed and lengthy, giving all relevant results. These are the following questions this section of the abstract research paper must answer:

• What did the study yield?
• What were the results in comparison to the hypothesis ?
• What were the predictions and were the outcomes similar to it?

In conclusion, our research revealed that eating chocolate high in flavanol shields humans from damaging UV rays, mainly because of its anti-inflammatory and antioxidant properties. The research indicates that HF chocolate lessens the acute inflammatory response to UV rays, by regulating the synthesis of proinflammatory cytokines and nitric oxide.

Discussions

Finally, you should discuss the conclusions and the author’s thoughts on the research. Whether the hypothesis proved to be right or not is mostly discussed here, along with the limitations or complications encountered during the research. It is necessary to mention this as a reader must be aware of the credibility and generalisability of the research.

Our research concludes by showing that cocoa flavanols have the potential to be a safe natural method of shielding skin from UV damage.

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Research Paper Abstract Example

Here is an abstract example for research papers to help you understand how abstracts are written:

Does the lockdown have a role in stopping COVID-19?

Every day the coronavirus is spreading, with deaths and fatalities increasing day by day. This has led to a nationwide lockdown all over the world. Our study aims to study the effect of lockdown days on the spread of coronavirus in countries. COVID-19 data from 49 countries was gathered from www.worldometer.com. As of May 5, 2020, there were 1440776 approved active cases of COVID-19 from the countries included in this study. Data on COVID-19 days and lockdown days was obtained from the websites of the official institutions of these 49 countries. Moreover, the correlation test was used to analyse the associations between total COVID-19 cases and the lockdown days. The lockdown days were seen to be correlated to the COVID-19 pandemic. The social-isolation phenomenon; the lockdown has been seen to prevent COVID-19 and the spread of this deadly virus. There are several concerns about the ability of the national healthcare system to effectively manage COVID-19 patients. To slow down the spread of this virus, it is necessary to take the strictest of actions. Even though Italy and Spain have the highest death rates because of COVID-19, there has been a sudden drop in the rates because of the strict measures taken by the government.

Frequently Asked Questions

When should i write an abstract.

You should write an abstract when you are completing a thesis or dissertation, submitting a research design or applying for research grants. You can also write an abstract if you are writing a book

What are things to avoid while writing an abstract?

You should avoid using passive sentences and future tenses. Avoid detailed descriptions as an abstract is supposed to be just a summary. Complex jargon and complicated long sentences should also be avoided as they take away the reader’s interest. Lastly, always address your problem statement in a good way. 

Should I cite sources in an abstract?

You should try to focus on showcasing your original work, rather than cite other work. Try to make your work as comprehensive and understanding so that your work is highlighted better. 

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Writing an abstract - a six point checklist (with samples)

Posted in: abstract , dissertations

The abstract is a vital part of any research paper. It is the shop front for your work, and the first stop for your reader. It should provide a clear and succinct summary of your study, and encourage your readers to read more. An effective abstract, therefore should answer the following questions:

• Why did you do this study or project?
• What did you do and how?
• What did you find?
• What do your findings mean?

So here's our run down of the key elements of a well-written abstract.

• Size - A succinct and well written abstract should be between approximately 100- 250 words.
• Background - An effective abstract usually includes some scene-setting information which might include what is already known about the subject, related to the paper in question (a few short sentences).
• Purpose  - The abstract should also set out the purpose of your research, in other words, what is not known about the subject and hence what the study intended to examine (or what the paper seeks to present).
• Methods - The methods section should contain enough information to enable the reader to understand what was done, and how. It should include brief details of the research design, sample size, duration of study, and so on.
• Results - The results section is the most important part of the abstract. This is because readers who skim an abstract do so to learn about the findings of the study. The results section should therefore contain as much detail about the findings as the journal word count permits.
• Conclusion - This section should contain the most important take-home message of the study, expressed in a few precisely worded sentences. Usually, the finding highlighted here relates to the primary outcomes of the study. However, other important or unexpected findings should also be mentioned. It is also customary, but not essential, to express an opinion about the theoretical or practical implications of the findings, or the importance of their findings for the field. Thus, the conclusions may contain three elements:
• The primary take-home message.
• Any additional findings of importance.
• Implications for future studies.

Example Abstract 2: Engineering Development and validation of a three-dimensional finite element model of the pelvic bone.

Abstract from: Dalstra, M., Huiskes, R. and Van Erning, L., 1995. Development and validation of a three-dimensional finite element model of the pelvic bone. Journal of biomechanical engineering, 117(3), pp.272-278.

And finally...  A word on abstract types and styles

Abstract types can differ according to subject discipline. You need to determine therefore which type of abstract you should include with your paper. Here are two of the most common types with examples.

Informative Abstract

The majority of abstracts are informative. While they still do not critique or evaluate a work, they do more than describe it. A good informative abstract acts as a surrogate for the work itself. That is, the researcher presents and explains all the main arguments and the important results and evidence in the paper. An informative abstract includes the information that can be found in a descriptive abstract [purpose, methods, scope] but it also includes the results and conclusions of the research and the recommendations of the author. The length varies according to discipline, but an informative abstract is usually no more than 300 words in length.

Descriptive Abstract A descriptive abstract indicates the type of information found in the work. It makes no judgements about the work, nor does it provide results or conclusions of the research. It does incorporate key words found in the text and may include the purpose, methods, and scope of the research. Essentially, the descriptive abstract only describes the work being summarised. Some researchers consider it an outline of the work, rather than a summary. Descriptive abstracts are usually very short, 100 words or less.

Adapted from Andrade C. How to write a good abstract for a scientific paper or conference presentation. Indian J Psychiatry. 2011 Apr;53(2):172-5. doi: 10.4103/0019-5545.82558. PMID: 21772657; PMCID: PMC3136027 .

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Writing an Abstract

What is an abstract.

An abstract is a summary of your paper and/or research project. It is NOT an introduction to your paper; rather, it should highlight your major points, explain why your work is important, describe how you researched your problem, and offer your conclusions. Typically, an abstract should be approximately 250-300 words; for OUR symposia, we ask for a maximum of 250 words. 

How do I prepare an abstract?

Review the components of an abstract.

The exact content of your abstract will depend on the status of your project, disciplinary norms, and feedback from your mentor; however, it should include several of the components listed below: 

• Problem:  What is the central problem or question you investigated? 
• Context: Provide brief background to place your project into context. Explain previous studies, concepts, or theoretical or critical frameworks relevant to your research (i.e., what’s already known or has been done on this topic). 
• Purpose: Outline how your work is contributing to the existing knowledge or is addressing gaps within your field (i.e., why this area of research is important and what’s the rationale for your work). 
• Hypothesis: What prediction(s) did you make based on your research question? 
• Methods: Describe the important methods you used to perform your research or evidence you examined. 
• Results: What are the major results, findings or arguments of the research project?  
• Interpretation: How do your results relate back to your central problem? 
• Implications: Why are your results important? What can we learn from them? 

Understand the structure of an abstract

Once you are familiar with the key components of an abstract, the next step is to understand how to organize these elements effectively. The composition of your abstract can also take different forms depending on the type of research and the conventions of your specific discipline. Below are common structures for projects in STEM fields and in the humanities suggested by The Writing Center . 

For STEM and experimental projects

• Objective/Goal/Significance (Why did you do it or why did it need to be done? Why is this question important/worth asking?) 
• Methods/Approach (What did you do? How did you attempt to answer this question?) 
• Results (What did you find/expect to find? What did the research reveal?) 
• Conclusions (What did you learn?) 

For humanities projects

(Version 1)

• Background (What’s the importance of your topic?) 
• Thesis (What argument or claim are you making?) 
• Theoretical Approach (if applicable) 
• Conclusion 

(Version 2)

• Background (Existing conversation, contribution of research) 

Consider your audience

For the purposes of the symposium, the wording of an abstract should be understandable to a well-read, interdisciplinary audience. Specialized terms should be either defined or avoided. 

Consult additional resources

• Creating an Abstract resource from  WUSTL University Libraries  
• How to construct a  Nature summary paragraph  (biological and biomedical sciences) 
• Abstract Guide  from the American Psychological Association 
• Writing an Abstract for Your Research Paper  from the University of Wisconsin Writing Center 
• View students’ abstracts from last year’s Fall and Spring Undergraduate Research Symposia 

Get help and feedback

Share your abstract with your mentor well in advance of the deadline to receive their input. Your abstract must have the approval of your research mentor or advisor. 

In addition you may wish to make an appointment  with The Writing Center at any stage of the abstract writing process.  

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Research Project Guide

3 Research Paper Abstract Example For Inspiration + How To Write Them

Discover 3 inspiring research paper abstract examples and learn simple tips to write your engaging abstract.

Nov 2, 2024

Starting a research project can be overwhelming, especially when staring at a blank document and wondering how to begin. One of the trickiest parts is creating an abstract that grabs attention while summarizing your work. This piece is your first chance to make a good impression. But don't worry. This guide will show you how to start a research project that effectively completes the job so you can conduct your research faster and more efficiently. Otio's AI research and writing partner is here to make the process smoother, helping you with everything from drafting to editing.

Table Of Contents

What is a research paper abstract, how to write research paper abstract efficiently, 3 research paper abstract example for inspiration, 7 best tools for writing research paper abstracts, supercharge your researching ability with otio — try otio for free today.

An abstract is like the teaser for your research paper , offering a snapshot of your study. Usually packed into a paragraph of 300 words or less, it covers the essentials in a specific order. First, it states the purpose of the study and the research problems you’re tackling. Then, it outlines the basic design of the study. It also highlights the significant findings or trends from your analysis. Finally, it wraps up with a summary of your interpretations and conclusions.

Why Your Abstract Matters

Your abstract isn’t just a formality. It’s a vital part of your research paper. Professors often ask for an abstract as a general summary of your work . This helps readers decide whether to dive into your paper's rest. So, include enough critical information, like summary results and observations, to make your abstract useful for others interested in your research.

Knowing When Your Abstract Is Ready

How do you know when your abstract is good to go? A simple rule is to put yourself in the shoes of another researcher doing a similar study. If your abstract was the only part of the paper you could access, would it meet your needs? Does it tell the whole story of your study? If not, it’s time to revise.

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This way, you can move from a jumbled reading list to a tidy first draft without tearing your hair out. Plus, Otio helps with writing research papers and essays faster. Researchers love its AI-generated notes and the ability to chat with links or entire knowledge bases. Otio is the AI research and writing partner you’ve been waiting for. Give it a try for free today!

Writing an Abstract for IMRaD Papers: What You Need to Know

If you’re tackling a research paper in social sciences or engineering, you’ll likely use the IMRaD format: Introduction, Methods, Results, and Discussion. The abstract is crucial because readers use it to decide whether they’ll dive into your entire paper. 

You’ll want to write the abstract after completing a full draft of your paper, summarizing the highlights as you go. Typically, an IMRaD abstract is one or two paragraphs long, ranging from 120 to 500 words. You’ll spend 25% of it discussing the research purpose and importance (Intro), another 25% on what you did (Methods), 35% on what you found (Results), and 15% on the research implications. Keep it concise and informative, giving readers a clear picture of your research.

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1. Health Sciences Research Paper Abstract Example

Obesity and vitamin D deficiency often occur together in patients. This study aims to determine if vitamin D supplements help with weight loss in obese patients. In a placebo-controlled trial, 100 obese women received vitamin D supplements over 24 weeks. 

BMI was the primary metric. The mean BMI decreased significantly in the vitamin D group (22.3 ± 0.2) compared to the placebo group (26.2 ± 0.3), with a notable effect (p ≤ 0·001). Our findings suggest vitamin D supplementation may aid weight loss programs.

2. Engineering Research Paper Abstract Example

Errors in the production chain impact digital video quality, and fixing these errors is challenging. We propose automatic error correction methods based on motion flow estimation and image correlation. Our new algorithms outperform existing techniques in quality and speed. This method eliminates the need for visual inspection and automatically restores video integrity.

3. Review Paper Abstract Example

A wide range of techniques has been proposed to produce and consume genetically modified food safely. This paper reviews progress and summarizes the current state-of-the-art technologies addressing food security challenges. This serves as a timely review, providing a risk-benefit analysis to inform future research in this area.

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How to Write an Abstract for a Research Paper: Writing Guide & Examples

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An  abstract is a brief summary of a research paper that is usually between 150 and 250 words in length. The purpose of the abstract is to provide a concise overview of the research paper's main questions, scope, methodology, findings, and conclusions. The abstract is usually located at the beginning of the paper, after the title page and before the main body of the text. It serves as a preview, and can be useful for readers who want to quickly determine whether the paper is relevant to their interests.

This guide describes all the key parts of this crucial segment and demonstrates how to write an abstract for a research paper . Research abstract examples and tips are also offered to help you create this section effectively.

What Is an Abstract in a Research Paper?

First, let’s cover what is an abstract in research. A research paper abstract is a synopsis of your full study. Specifically, writing an abstract involves extracting the main aspects of your work in a given order. These components include your study purpose and study questions, design, main findings, interpretation, and conclusion. Based on this summary, readers will decide whether to look at the rest of your project. Hence, you must include sufficient key information as this makes the abstract of a research paper useful to your audience or professor. To determine if you have included adequate data, imagine yourself as a researcher conducting an investigation. Consider an abstract as the only section, and think about how much information you provided. Are you satisfied with it? Does it describe your study adequately? Revise your writing accordingly. But don’t be confused. An abstract is a self-contained text, not a part of a research paper introduction . Remember that scientific paper abstracts must highlight your manuscript’s selling point and lure a reader to go through it.  At first, it may sound difficult. But this guide will reveal every essential writing step. Alternatively, you can also contact StudyCrumb and pay to write research paper to avoid any further individual work.

What Is the Purpose of an Abstract?

The aforementioned definition demonstrates why abstract writing is important. Nevertheless, it is also necessary to understand the purpose of an abstract in a research paper. Well-written abstracts serve multiple objectives. For example, they communicate your key findings and allow readers to make an informed decision about how relevant your article is based on their interests and whether they should consider it. Reading an abstract of a scientific paper also prepares reviewers to grasp the key points and follow your detailed points and analyses. Another purpose of an abstract is for classification. Online libraries or journal databases, and search engines use abstracts for indexing published works. This allows users to retrieve what they are looking for quickly rather than reading full texts. Thus, a good abstract must include several key terms that potential readers would use for searching, as this makes discovering your work easy.

How Long Is an Abstract?

An abstract is perhaps the only section of your manuscript that is limited regarding how many words you can use. In general, it is usually limited to 150 and 300 words. However, for research paper abstract, most guidelines stick to the range of 200 and 250 words both for simple or small manuscripts and specific types of papers such as theses or dissertations. This restriction should not be exceeded no matter what. However, how long your abstract can be is influenced by the assignment instructions. Thus, it is essential to comply with any guidelines about the abstract length.

What Makes a Good Abstract for a Research Paper?

While the length aspect is vital, it is also essential to write a good abstract. This entails providing an honest and complete synopsis of your work through a coherent flow of ideas. An abstract in a paper should also be self-contained without the need for readers to peruse other parts for further information. Therefore, knowing how to write an effective abstract for a research paper can make a difference. Here are elements that make a good abstract for a research paper:

• Use one finely written, concise, and coherent paragraph that stands individually as an information unit.
• Add all the basic academic features of your manuscript, including background, objective, focus, method, findings/results, and conclusion.
• Do not write about information not covered in your document.
• Ensure the section is understandable to a wide audience and your subject-specific readers.
• Focus on issues instead of people.
• Develop it with the language of your main paper in a simple format for general readers.
• Put it just after your title page.

When to Write an Abstract?

Lengthy texts such as scholarly manuscripts usually require students to write an abstract section. You might also need to write an abstract for a scientific paper when:

• Submitting reports to journals for publication or peer review.
• Working on a book chapter proposal.
• Applying for research grants.
• Completing conference paper proposals.
• Composing book proposals.
• Writing theses or dissertations.

For undergraduates, you may be required to include an abstract in a research paper for others who have not read your main manuscript. Regardless of the type of work you are dealing with, it is necessary to draft your abstract after completing writing, as this enhances accuracy and conformity with other segments of a report.

What to Include in an Abstract of a Research Paper?

Another crucial aspect that you must consider is the structure of an abstract. Good abstracts are well-organized, which makes them more informative. Scientific guidelines emphasize the IMRad format as a standard way of unifying this section. The parts of an abstract in a research paper based on this system consist of: 

Introduction

• Discussion.

Do not forget to balance all your sections properly regarding methods included under each heading. Using this setup allows you to write a helpful, concise, and easy-to-understand abstract of a paper. Nonetheless, some  instructions may necessitate additional subheadings, particularly works such as clinical trials, observational studies, case studies, and meta-analyses. Hence, you should be attentive to your task requirements.

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As the first section, an introduction reveals to readers what your work is about. Consequently, you should know how to start an abstract by writing a good beginning segment. Here, describe the scope, question/hypothesis, main objectives, and rationale for your study. In most cases, you can frame this part in 2-3 sentences. Each of them should describe a specific point to maximize word use. The introduction to an abstract part of a paper offers a background to your investigation, which should smoothly lead to an explanation of the methods that were used. Be careful here because writing an abstract for a research paper containing a lengthy introduction takes up space for other important sections. This affects the quality of an abstract in a scientific paper. Therefore, ensure that you provide brief, specific, and relevant information that keeps readers interested. Look at this example of an abstract introduction:

The present study explored the effect of technology in enhancing employment opportunities today. The benefits of technology have been examined in exploratory and descriptive studies. Nevertheless, no study has considered how technology increases employment opportunities.

Here are some more examples of how to begin your abstract. 

Methodology in research is usually the second longest part of your abstract paragraph. The focus here is on providing adequate information about what you did and how. Specifically, give essential facts about your study design, setting, sample, data collection and analysis instruments, measures, and parameters. The methodology part is vital as you write the abstract section of a research paper because it helps in verifying your manuscript’s credibility. An editor will ignore an abstract missing a methods section or that does not have a clear explanation. Therefore, practice caution and professionalism when writing this unit by including enough details and conveying the maximum quantity of information with few words. If you are unsure of how to organize this segment, consider this example of a good abstract methodology:

This study used a qualitative exploratory design in which data was collected from existing studies and documents. A sample of 120 peer-reviewed works and documents were analyzed using an interpretive paradigm.

This section is about what you found after conducting your research. It is an indispensable and longest part of a research abstract because anyone reading intends to gain insights into your study findings or which data your investigation uncovered. Therefore, avoid compromising its quality by ensuring that you include as much factual information about your results as the word count allows. Drafting the results of an abstract for research papers is not easy. However, the details you should express here include the number of participants, outcomes of your analysis, and actual data such as numbers or mean, etc. Remember to be descriptive and prioritize fresh and substantiated findings contradicting previous studies. Also, indicate any limitations regarding your results’ reliability and accuracy. Look at this sample abstract results:

Nine studies did not meet the research criteria and were excluded. An analysis of the remaining 91 studies revealed five major themes, including ease of skills acquisition, work-at-home opportunities, globalization, digital marketing, and increased networking.

This is a part of the abstract structure where you divulge what readers can take home from your work or what your results mean based on how you interpreted the issue. Use a few but precise sentences to highlight the findings relating to what your study was about. You should also mention any unexpected or important outcomes. Additionally, you can offer a personal judgment regarding the practical or theoretical implications of your results or how significant they are for the study field as a whole. While conclusions are very short parts of an abstract, they are the most impactful on average audiences since readers usually believe authors and consider their views reliable. For this reason, ensure that you are honest when writing an abstract in research by limiting your claims to what your data exposes. Here is an example of a scientific abstract conclusion:

Technology has a positive effect on employment as it creates more job opportunities through remote work. It also enables people from any part of the world to learn essential skills, which enhances their job prospects.

Check our guide on creating a concluding section if you want to know more information on how to write a conclusion for a research paper .

An abstract for research paper must also contain a range of keywords. These are important words or phrases that act as search terms for finding your work quickly. Therefore, in addition to knowing how to write an abstract for a research paper and what to write in an abstract, you should understand how to include useful keywords that capture essential aspects of your manuscript. Think about how you can find your work online. Which words or a combination of them will be typed in a search box? You should use those terms. Acronyms such as OCD, meaning obsessive-compulsive disorder, may also be included. While you are not limited regarding the number of keywords to be used, it is recommended to include 3-5 keywords. Keep in mind that the research abstract format for keywords is a separate line beginning with an indention, like a paragraph below your abstract. Indicate it by italicizing the word Keywords followed by a colon and space look like this:

Keywords: international marketing, globalization, medium-size businesses, B2B, adaptation.

Do not italicize your terms.

How to Write a Research Paper Abstract Step-By-Step

Shrinking a manuscript that you have prepared for several days, weeks, or months into a 300-word paragraph can be challenging when preparing the abstract. However, you can follow specific tricks on how to write an abstract for a paper to address the difficulty. Before you begin, you must consider the instructions provided carefully concerning aspects such as spacing, fonts, word limit, and subheadings. In this section, you will learn how to write a good abstract for a research paper step by step.

1. Explain Your Research Purpose

Students usually start an abstract for a research paper by identifying the study's purpose. Here is where you consider the reasons for conducting your research. For example, if your study problem is about technology and employment, so what? Why should readers care about your topic? In this part of the abstract, you can describe what was solved or why you feel your topic is relevant. Use this section to inform readers about your key argument, as it helps in generating a good abstract for a research paper. Remember to be descriptive by explaining the difficulties of your topic or gaps in knowledge you will address and how your investigation will affect the issue. Consider triggers such as why you conducted your research, how you performed it, what you found, the significance of your study and its results, and why others should read your paper.

2. Define a Research Problem

The next step towards writing a good abstract involves explaining the central issue or problem statement behind your investigation or that your paper addresses. Remember, you first identified your purpose, so build on that by focusing on one key problem. Abstracts for scientific papers usually include this section to demonstrate the scope of a manuscript. Avoid using too much jargon here by making it easy for your readers to see your main message. If your abstract does not include the primary question, then you do not understand why you are conducting your study. Remember that when writing a research abstract, your purpose and problem form the backbone of the work. Thus, do not leave this step until you have one concise study problem.

3. Introduce Your Research Approach

After identifying your research problem, you now need to explain how you addressed it in this part of an academic abstract. In other words, how did you conduct your study following your key problem? When writing an abstract for a paper, let your audience know what you did exactly to get to the findings. Abstract in research paper may include approaches such as experimentation, case study, document analysis, or simulation. You must also highlight the extent of a manuscript, such as how many documents were analyzed and which variables were used. While this section of an abstract for a paper may require a long sentence, ensure that anyone can read it without needing to pause in the middle.

4. Discuss Results

After clarifying your approach, your study abstract must disclose what was found. What is the solution to your research problem? Did you confirm your hypothesis? Remember to be direct, detailed, and clear. Specifically, writing a scientific abstract requires that you describe your results in exact numbers or percentages. This allows you to create an abstract of research paper that cannot be misinterpreted easily. Also, avoid vague words such as “significant”, “large”, “very”, or “small.” In this section, an abstract in a research paper should not include exaggerations or create expectations that your manuscript cannot fulfill. Rather, the focus should be on your most important findings to engage readers. However, do not attempt to fit all your results in this part.

5. Wrap Up Your Scientific Paper Abstract

You should also conclude an abstract after completing the aforementioned steps. This enables you to finish up a research paper abstract and end it. Here, describe what your results mean and why your overall work is important. Mention what the answer to your research problem implies and identify if it is specific or general. For example, are your results generalizable to a wider population or selected groups? When creating an abstract, describe why your readers should care about your results rather than re-stating the findings. What can people do with your study? As stated previously, an abstract is a brief summary in the beginning of a research paper or any other scientific work. Read our guide on how to write an abstract for a research paper and how to structure it for more explanation.

Research Paper Abstract Examples

As you can see, constructing an abstract is not difficult if you follow the above-mentioned steps. You can now compose your own one easily. Nonetheless, if you are still confused or unsure whether you are on the right path, feel free to look at different examples of an abstract for a research paper. You can also consider these three examples of abstracts in research papers and use one of them as a draft for your work. Need a research proposal example ? You will find it in one more blog on our platform. Research paper abstract example 1

Abstract page example 2

Example of an abstract for a research paper 3

Research Paper Abstract Format

Another important consideration is complying with the specified abstract writing format to avoid any confusion on how this section should be completed. Your layout depends on the citation style being used. Specifically, the main styles, such as APA, MLA, and Chicago, have individual rules regarding how to format an abstract in a research paper. However, to make it simple, an abstract template is usually provided to help you with the organization. In general, observe and stick to your paper’s requirements.

Extra Tips for Writing an Abstract

Writing an abstract for a research paper should not be a complex process. You already have a good idea about how to make an abstract after reading the previous sections. Remember that writing this segment is an essential part of your work because it prefaces the entire manuscript. Still, it is usually the last segment of your project to be written, which means that you should summarize your research easily. However, this can be a daunting undertaking for some students. Below are additional abstract writing tips and guidelines to help you.

Draw Inspiration From Research Paper Abstracts Examples

Even if you follow this article’s guidelines, without writing practice, it can be difficult to create good abstracts. Therefore, if you are still struggling to write, you can draw inspiration from sample abstracts. These can be found in peer-reviewed articles or course books in your school library or from online databases. Focus on samples from your study field e.g., science abstracts examples if you are into the sciences or those for social sciences if it is your field. Seek assistance from your professor to ensure that you consider a good abstract paper example. Another option is reading how to write an abstract example segment, as this offers you a quick refresher on composing abstracts.

Prepare an Abstract Outline

It is also essential to write a research abstract outline if you have not done so already. Creating an outline will help you write your actual abstract paper efficiently. Make sure to place your key argument at the top before reading each subheading of your manuscript as a starting point. Write one-sentence summaries of your main sections as you read in the order that they appear in your work. Also, do not forget to summarize your conclusion. What goes in an abstract, however, is limited. For example, the literature review cannot be included. Rather, you can state in a sentence how your work fits into the wider academic discourse.

Write Abstract From the Ground Up

While your abstract is a synopsis, you should write it from scratch and as a completely different part of your manuscript. Copying and pasting quotes or paraphrasing sentences should be avoided. Use new phrases and vocabulary instead when writing this section to keep it engaging and free of redundant words or sentences. Read how to write abstract for research paper for more clarification about what you should include.

Make Your Research Abstract Concise

Ensure that your research paper abstract is clear, concise, and coherent. It should be no more than 200-250 words. If it is longer, cut it down where necessary. Since readers just want to get the overall view of your claim, you can exclude unimportant information and construct brief sentences. This is how to write a paper abstract:

• Include essential information found in the paper only
• No exaggerations or inclusion of new ideas
• No use of abbreviations that are found only in the body because the abstract should be self-contained
• No dwelling on previous studies since this is a synopsis of your report.

Mistakes to Avoid When You Write an Abstract for a Research Paper

Even if you know how to write research abstract, check it several times to ensure that what you included agrees with your manuscript content completely. Avoid these common mistakes:

• Research paper abstracts should not include catchy phrases or quotes focused on grabbing your readers’ attention.
• Do not use direct acronyms because they require further explanation to help readers understand.
• Citing other studies is not needed.
• Do not use confusing/unnecessary terms or obscure jargon, as the general audience may not understand them.
• A scientific paper abstract should not be too specific. Rather, consider a wider overview of your paper.
• Do not include long quotations, figures, or tables. They take up precious space, and your audience does not need them.

Bottom Line on How to Write a Research Abstract

This guide discussed extensively how to write the abstract of a research paper. Reaching this section means that you now understand what is an abstract in writing. The article also provided several abstract writing examples to help you grasp the described ideas. It is your turn now to develop a nice abstract by applying what you have learned. Do not fret if you are still confused or cannot recall some points. You can just re-read a section to fully understand all concepts.

Our professional writers can compose a top-notch abstract or any other section of a research paper. You can also easily ask for comprehensive assistance with any task and get excellent work strictly according to your deadlines.

FAQ About How to Write an Abstract

1. what is an abstract.

An abstract is a takeaway from your research. Specifically, abstracts are standalone sections that describe an issue, techniques utilized in exploring the issue, and the outcome of these procedures. While each study field specifies what to include in this section, it should be a concise synopsis of your work.

2. Where does an abstract go in a research paper?

Place your research paper abstract at the beginning of your work immediately after a title page and before your table of contents. However, some manuscripts have an acknowledgments section. Here, your abstract appears after that part. It should also be on its page and in a single paragraph.

3. Do you write an abstract first or last?

Even though it appears at the top of your work, ensure that you write an abstract last after completing your research paper since it involves abstracting contents from your manuscript. This allows you to align this section with other parts, such as the title, introduction, and background.

4. Do I need to cite references in a research paper abstract?

It is usually inappropriate to include any reference within abstracts because this section should demonstrate original research. The abstract of a research paper must include a description of what you did in your paper, what you argued, and what you found. You will cite specific sources in your manuscript’s body.

5. What should not be included in an abstract?

These are what you shouldn’t include in the abstract of a research paper:

• Long sentences
• Excessive details or lengthy contextual information
• Filler words, redundant phrases, and repetitive information
• Incomplete sentences
• New information not found within your main text.

6. What tense should I use when writing an abstract?

Write an abstract using active voice. However, a substantial part of this segment may need passive sentences. Nonetheless, use concise and complete sentences when writing your abstract. Specifically, get to your point quickly and focus mostly on the past tense since you are reporting completed research.

Joe Eckel is an expert on Dissertations writing. He makes sure that each student gets precious insights on composing A-grade academic writing.

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What is abstract science?

What is Abstract Science?

Scientific inquiry is often associated with concrete, measurable observations and tangible results. However, there is a branch of science that delves into the non-material, non-physical, and abstract realm – abstract science. In this article, we will explore the concept of abstract science, its significance, and its importance in the scientific landscape.

Abstract science, also known as abstract thought or abstract research, is a type of scientific inquiry that deals with intangible concepts, ideas, and theories. It is concerned with understanding the abstract, universal, and essential aspects of human experience, knowledge, and reality. Abstract science is not limited to a specific domain or discipline, but rather draws from and contributes to various fields, including philosophy, mathematics, physics, and cognitive science.

Key Characteristics of Abstract Science

Abstract science exhibits several distinct features that set it apart from experimental or empirical sciences:

• Non-material focus : Abstract science focuses on abstract concepts, ideas, and theories, rather than physical entities or objects. • Theoretical frameworks : Abstract science relies on theoretical frameworks, models, and axioms to understand and describe abstract phenomena. • No direct empirical evidence : Abstract science does not rely on direct empirical evidence, as the objects of study are not directly observable. • Inference and deduction : Abstract science employs inference and deduction to develop and test abstract theories and models. • Open-to-question structure : Abstract science is characterized by an open-to-question structure, allowing for continuous refinement and revision of abstract theories and models.

Significance of Abstract Science

Abstract science plays a vital role in various aspects of human inquiry, including:

• Philosophy : Abstract science contributes to philosophical debates about the nature of reality, knowledge, and truth. • Mathematics : Abstract science underlies many mathematical theories and models, providing a framework for understanding and pattern recognition. • Cognitive science : Abstract science informs our understanding of human cognition, perception, and behavior. • Theoretical physics : Abstract science is essential for developing fundamental theories in physics, such as quantum mechanics and relativity.

Examples of Abstract Science

Some notable examples of abstract science include:

• Mathematics : Abstract algebra, topology, and set theory • Philosophy : Metaphysics, epistemology, and ethics • Cognitive science : Cognitive psychology, artificial intelligence, and human-computer interaction • Theoretical physics : Quantum mechanics, relativity, and string theory

Challenges and Limitations of Abstract Science

Abstract science faces several challenges and limitations, including:

• Lack of empirical evidence : Abstract science often struggles to provide empirical evidence for its theories and models. • Complexity and ambiguity : Abstract concepts can be complex and ambiguous, making it challenging to develop clear and testable theories. • Interdisciplinary nature : Abstract science often draws from multiple disciplines, which can lead to conflicting perspectives and lack of agreement. • Public understanding : The abstract nature of abstract science can make it difficult for non-experts to understand and appreciate its significance.

In conclusion, abstract science is a vital and fascinating branch of scientific inquiry that explores the abstract, non-material, and essential aspects of human experience. While it faces challenges and limitations, abstract science has significant contributions to make in various fields, from philosophy to theoretical physics. As we continue to push the boundaries of human knowledge, it is essential to recognize and appreciate the importance of abstract science in shaping our understanding of the world and the human experience.

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Superior pattern processing is the essence of the evolved human brain

Mark p mattson.

• Author information
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Edited by: J. Michael Williams, Drexel University, USA

Reviewed by: Lei Chang, Chinese Univerisity of Hong Kong, Hong Kong; Lennart Verhagen, Radboud University Nijmegen, Netherlands

*Correspondence: Mark P. Mattson, NIH Biomedical Research Center, 5C214, 251 Bayview Boulevard, Baltimore, MD 21224, USA e-mail: [email protected]

This article was submitted to Evolutionary Psychology and Neuroscience, a section of the journal Frontiers in Neuroscience.

Received 2014 Apr 30; Accepted 2014 Aug 5; Collection date 2014.

This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

Humans have long pondered the nature of their mind/brain and, particularly why its capacities for reasoning, communication and abstract thought are far superior to other species, including closely related anthropoids. This article considers superior pattern processing (SPP) as the fundamental basis of most, if not all, unique features of the human brain including intelligence, language, imagination, invention, and the belief in imaginary entities such as ghosts and gods. SPP involves the electrochemical, neuronal network-based, encoding, integration, and transfer to other individuals of perceived or mentally-fabricated patterns. During human evolution, pattern processing capabilities became increasingly sophisticated as the result of expansion of the cerebral cortex, particularly the prefrontal cortex and regions involved in processing of images. Specific patterns, real or imagined, are reinforced by emotional experiences, indoctrination and even psychedelic drugs. Impaired or dysregulated SPP is fundamental to cognitive and psychiatric disorders. A broader understanding of SPP mechanisms, and their roles in normal and abnormal function of the human brain, may enable the development of interventions that reduce irrational decisions and destructive behaviors.

Keywords: evolution, hippocampus, language disorders, religion and science, neuronal network

Introduction

The fundamental function of the brains of all animals is to encode and integrate information acquired from the environment through sensory inputs, and then generate adaptive behavioral responses. Sensory information is first rapidly encoded as patterns inherent in the inputs, with visual and auditory patterns being most extensively studied in mammals (Wang et al., 2009 ; Sweeny et al., 2011 ). The large numbers of encoded images and sound patterns can then be recalled and mentally manipulated in ways that enable comparisons of different patterns and, at least in the human brain, the generation of new patterns that convey objects and processes that could possibly exist, or are impossible or implausible. In this article, I define pattern processing as the encoding and integration of perceived or mentally-fabricated patterns which can then be used for decision-making and for transfer of the patterns to other individuals. Examples of types of pattern processing that are common among non-human primates and, in many instances, lower mammals and are therefore not uniquely human include: (1) Cognitive maps of the physical environment, such as the encoding and recall of locations of food sources, potential predators and navigation landmarks; cognitive mapping is critically dependent upon the hippocampus (Pearce et al., 1998 ; Spiers et al., 2001 ); (2) The ability to distinguish individuals of the same species, and their emotional state, based on features of their faces (Little et al., 2011 ; Parr, 2011 ; Yovel and Freiwald, 2013 ); (3) The use of gestures to capture the attention of, and to communicate a desired response from, other individuals (Liebal et al., 2004 ). It has been suggested that communication via gestures, which is well-characterized in apes, was a precursor to language during human evolution (Liebal et al., 2004 ; Tomasello, 2008 ).

The cognitive repertoire of humans far exceeds that of all other animals, and understanding the neurobiological basis of this superiority is therefore of interest not only to scientists, but also to society. As humans evolved from their anthropoid ancestors, and the size of their cerebral cortex expanded, novel pattern processing capabilities emerged. The main purposes of the present article are to describe the superior pattern processing (SPP) capabilities of the human brain, to forward the hypothesis that SPP is the neurobiological foundation of human sociocultural evolution, and to describe the roles of aberrant SPP in some major neurological disorders. The types of pattern processing that appear to occur robustly, if not uniquely in the human brain and are therefore considered as SPP include: (1) Creativity and invention, which have resulted in the development of tools, processes and protocols for solving problems and saving time, and the arts (Goel, 2014 ; Orban and Caruana, 2014 ; Zaidel, 2014 ). Examples include all aspects of agriculture, transportation, science, commerce defense/security, and music; (2) Spoken and written languages that enable rapid communication of highly specific information about all aspects of the physical universe and human experiences; (3) Reasoning and rapid decision-making; (4) Imagination and mental time travel which enables the formulation and rehearsal of potential future scenarios; and (5) Magical thinking/fantasy, cognitive process that involves beliefs in entities and processes that defy accepted laws of causality including telepathy, spirits, and gods (Einstein and Menzies, 2004 ). A major purpose of the present article is to forward the proposal that not only is pattern processing necessary for higher brain functions of humans, but SPP is sufficient to explain many such higher brain functions including creativity, imagination, language, and magical thinking.

The results of functional brain imaging studies and of patients with brain injury suggest that multiple brain regions and neuronal networks are involved in each of the different types of SPP. Evolutionary considerations suggest that three brain regions may be particularly important in SPP in humans, the visual cortex, the prefrontal cortex and the parietal—occipital—temporal juncture (Figure 1 ). In humans, the cerebral cortex involved in processing visual inputs is considerably larger than lower anthropoids, likely due an evolutionary transition from being nocturnal, arboreal and relatively solitary, to being diurnal, ground-based and social (Passingham and Wise, 2012 ). Two major changes in the visual system selected for during this transition were forward-positioned eyes to allow binocular vision and depth perception, and changes in the structure of the retina to include a fovea and color vision (Kaas, 2012 ). The abilities to efficiently process complex visual and auditory patterns are also particularly important because of their centrality to language. Functional brain imaging studies have shown that, in addition to Broca's and Wernicke's regions (Damasio and Geschwind, 1984 ), language is processed in a distributed neuronal network that involves multiple cortical regions (Dick et al., 2013 ). While several regions of cerebral cortex are larger in the human brain compared to other anthropoids, the region that evolved most in the human lineage is the prefrontal cortex (Passingham and Wise, 2012 ). Some functions of the prefrontal cortex have been revealed by neuroanatomical, lesion and imaging studies and include insight and rapid decision-making (Passingham and Wise, 2012 ), episodic memory (Allen and Fortin, 2013 ), and complex social behaviors (Teffer and Semendeferi, 2012 ). Detailed consideration of the regional neuroanatomy of the different types of SPP is well beyond the scope of the present article, and is considered in recent articles as follows: creativity (Zaidel, 2014 ); language (Hagoort and Indefrey, 2014 ); imagination and mental time travel (Polyn and Sederberg, 2014 ) and magical thinking (Badzakova-Trajkov et al., 2011 ).

Superior pattern processing (SPP) capabilities of the human brain evolved in association with expansion of the cerebral cortex . A comparison of the gross anatomy of the brains of humans and chimpanzees ( Pan troglodytes ) reveals considerable expansion of three regions in humans, the prefrontal cortex, the visual cortex, and the parietal—temporal—occipital juncture (PTO). Examples of SPP capabilities of humans are listed next to the human brain. Examples of pattern processing capabilities of great apes are listed adjacent to the image of the chimpanzee brain. Source of brain images is Wikimedia Commons. Scale bar, 1 cm.

Pattern processing is an evolutionarily conserved function of nervous systems

“ The difference in mind between man and the higher animals, great as it is, is certainly one of degree and not of kind.” Charles Darwin, The Descent of Man .

What is the reason that the brain of our species is capable of cognitive feats well beyond even our closest non-human primate relatives? The human brain is remarkably similar to the brains of non-human primates and lower mammals at the molecular and cellular levels, suggesting that the human brain deploys evolutionarily generic signaling mechanisms to store and retrieve large amounts of information and, most remarkably, to integrate information in ways that result in the generation of new emergent properties such as complex languages, imagination, and invention. Here I review neurobiological aspects of pattern processing in birds and lower mammals and propose that an evolutionarily rapid expansion of pattern processing capabilities is the major reason that the human brain has capabilities considerably beyond those of lower species.

From homing pigeons to the swallows that return from Argentina to Capistrano each year, many bird species are capable of highly precise navigation. Accumulating evidence suggests that migrating birds encode navigational maps within the neuronal circuits of their brains. For example, in one study it was shown that adult crowned sparrows navigate toward a wintering area known from the previous year and can successfully correct for displacements of over 1000 miles (Thorup et al., 2007 ), suggesting the existence of a long-range experience-dependent global positioning system in the brains of these animals (Thorup and Holland, 2009 ). Acquiring food (foraging) and storing food are two spatial PP-mediated behaviors that, as in mammals (see next section) involve neural circuits in the hippocampus and associated higher cortical structures involved in sensory (particularly vision and olfaction) integration and processing (Bingman et al., 2003 ). The size of the hippocampus has been shown to change by as much as 30% in response to food-storing experiences and the increased hippocampal size associated with memorizing the location of food caches involves an increase in the total number of neurons in this brain region (Clayton, 1998 ; Biegler et al., 2001 ). Song learning and imprinting are two other well-known and well-studied types of learning and memory that are, as with all forms of higher learning, based on pattern processing (Healy and Hurly, 2004 ). As is true for mammals, learning and memory processes involved in pattern processing in birds involve activity at synapses that deploy the neurotransmitters glutamate, GABA and norepinephrine (Gibbs et al., 2008 ).

The human brain has retained many features of brain structure and cellular organization of the brains of birds and lower mammals, but has greatly elaborated upon them by developing more robust cortical neuronal networks involved in the processing of visual and auditory patterns. As in lower mammals, being aware of one's position in the environment, and remembering the locations of resources (food, shelter, etc.) and hazards (predators, cliffs, etc.) is of fundamental importance for the survival of humans. However, the encoding of visual inputs into “cognitive maps” of spatial relationships between objects in the environment (spatial pattern separation), and the encoding of auditory inputs, is necessary but not sufficient for the advanced PP abilities of humans including imagination, invention, and pattern transfer (language). The evidence suggests that expansion of the visual cortex, prefrontal cortex, and parietal—temporal—occipital (PTO) association area enabled the SPP that defines the human intellect capacity and all of its manifestations, including consciousness, language and mental fabrication and time travel. The remainder of this article describes some of the salient evidence for SPP as the basis of most, if not all, higher cortical functions in humans.

Neural substrates of superior pattern processing: a conserved dynamic cytoarchitecture of intellect

The processing of visual images sensed by the eyes involves transfer of the features of those images to neuronal circuits in the primary visual cortex where the images are encoded in neurons in spatially-localized and oriented receptive fields comprised of cooperating neural networks that encode object identity and location (Rao and Ballard, 1998 ). The well-known homunculus of the primary somatosensory cortex provides a clear neuronal network structure-based map of the physical location on the body of the sensory receptors for pressure, pain, and temperature. Pattern encoding by the visual and somatosensory systems is therefore relatively easy to understand because the location of the sensory receptors themselves is “imprinted” in the cellular architecture of the corresponding primary sensory cortices. On the other hand, pattern encoding of auditory input is based largely on the quality and temporal ordering of sounds. In the cases of taste and olfaction, the quality of the tastes and odors is critical information that is encoded, but at the level of the neuronal networks and synapses pattern encoding occurs by mechanisms similar to those of the auditory system. Thus, odors evoke complex spatiotemporal activation of olfactory bulb neurons and a firing rate-based representation of the odors in the piriform cortex (Haddad et al., 2013 ).

While bigger in size, when viewed under the microscope the human brain is remarkably similar to those of non-human primates and lower mammals. At the cellular and molecular levels, there is little to distinguish our brain from those of species that preceded us in evolutionary history. The major cell types (neurons, astrocytes, oligodendrocytes, and microglia) are similar in their morphological features, molecular phenotypes and functions. Neurotransmitters are identical with glutamate and GABA being the major excitatory and inhibitory transmitters, and monoamines and acetylcholine being prominent secondary transmitters in all mammals. Similarly, gasotransmitters (nitric oxide, carbon monoxide, and hydrogen sulfide), neuropeptides and neurotrophic factors (e.g., neurotrophins, fibroblast growth factors, and insulin-like growth factors) are conserved (Amaral and Campbell, 1986 ; Jones, 1986 ; Barde, 1994 ; Mustafa et al., 2009 ). In addition, a range of behaviors including learning and memory, anxiety, aggression and others are modified in the same ways by the same drugs in humans and lower mammals. Moreover, genes that encode proteins involved in brain development, function and/or disease are largely conserved; indeed, genetic mutations that cause psychiatric or neurodegenerative disorders in humans often induce similar neurochemical, cellular and behavioral phenotypes in transgenic animals (McGonigle, 2013 ). Thus, findings from neuroscience research has confirmed the general conclusion of Charles Darwin who proposed in The Descent of Man that the minds of humans and related species are fundamentally similar (Darwin, 1871 ).

While some principles by which the brain uses pattern recognition and encoding to represent the past and the future have been established, a clear understanding of the underlying molecular and cellular mechanisms is lacking. How the encoded patterns are recalled and processed to generate enduring memories of the different patterns and their association with other encoded patterns (e.g., associations of the image of an object with the sound, smell, or feel of that object) is also not well understood. Nevertheless, the human brain is capable of using stored information to generate novel images, sounds, and other patterns in the processes of imagination and invention.

The term intelligence has been defined in different ways by psychologists and neuroscientists, but a general definition proposed by one group of eminent scholars is “A very general mental capability that, among other things, involves the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly, and learn from experience.” (Gottfredson, 1997 ). All mammals are able to learn and to make decisions and choices based upon their prior learning experiences, a fundamental aspect of reasoning. Mice and rats have about 1 billion neurons in their nervous system whereas humans have 100-fold more neurons with approximately 30 billion being in the brain. Neuroanatomical and neurochemical considerations described in this section suggest that the superior intellectual capabilities of humans are solely or largely the result of the increase in the number of neurons and synapses that mediate enhanced encoding, integration and inter-individual transfer of patterns. As referenced above, there is little or no uniqueness in the structural or functional properties of the neuronal circuits that mediate intelligence in humans (Figure 2 ). Moreover, the intellectual capability of any individual requires the integrated function of pattern-processing networks distributed throughout the cerebral cortex (Duncan, 2010 ), indicating that there is no single brain structure responsible for the mental superiority of humans.

Structural features of the brains of mammals are conserved from rodents to humans . The upper drawings show the hippocampal formation of an adult human, a kitten and a young mouse. The lower two drawings show the cellular organization of the cerebral cortex of an adult human and an adult mouse, both of which exhibit six cell layers. All of the drawings are adapted from Santiago Ramon y Cajal (DeFelipe and Jones, 1988 ). CA, cornu ammonis; DG, dentate gyrus; SUB, subiculum.

The cellular and molecular mechanisms of pattern processing have been most intensively investigated in nerve cell circuits of the hippocampus, a brain region that plays a critical role in spatial learning and memory (Yassa and Stark, 2011 ). When our eyes and ears are open they are continually detecting images and sounds, the details of which are transiently encoded in nerve cell circuits in the visual and auditory regions of the cerebral cortex, respectively. The neurally-encoded visual and auditory patterns (as well as olfactory, gustatory and touch/pain inputs) are then transferred into hippocampal circuits via neurons in the entorhinal cortex. Inputs from the other senses (olfactory, gustatory, touch/pain) are also communicated to the hippocampus. Learning and long-term memories of such experiences require the hippocampus in humans, monkeys, rodents, and birds (Stella et al., 2012 ). For example, birds that store food in caches are able to remember, in a hippocampus-dependent manner, not only the locations of the caches, but also what they placed in the cache and when they put it there. Moreover, such birds can modify their caching strategy when they perceive that another bird (a potential pilferer) is watching them (Emery and Clayton, 2001 ). Thus, similar to humans, these birds have an episodic memory system that is modified by social context.

Electrical recordings from neurons in the hippocampus of freely-moving rats have shown the existence of “place cells,” neurons that fire action potentials when the rat is in a specific location of the same test arena (Moser et al., 2008 ; Burgess and O'Keefe, 2011 ). Other neurons fire in response to cues within the test chamber, regardless of the location of the test arena, suggesting that hippocampal circuits encode both spatial and episodic memory information (Leutgeb et al., 2005 ). Lesions of neurons in regions CA1 and CA3 of the hippocampus in rats result in impaired ability to remember a sequence of spatial locations (Lee et al., 2005 ), and selective destruction of dentate granule neurons results in an impaired ability of rats to learn adjacent spatial locations in a radial arm maze (Morris et al., 2012 ). Remarkably, a recent study demonstrated the neuronal network activity basis of the envisioning of the location of a food source by rats (Pfeiffer and Foster, 2013 ). Electrical activity was simultaneously recorded from approximately 200 neurons in the hippocampus of rats while they were foraging for food. Prior to initiating navigation toward a potential food source, there occurred activity in a sequence of neurons (place cells) that accurately tracked the progression of the rat from its current location to the remembered location of the food source. These findings provide evidence that rats are capable of visual imagery in that neuronal ensembles that encode a specific location are activated when the rat is “contemplating” that location.

Neurons in the dentate gyrus of the hippocampus play a particularly important role in spatial pattern separation (PS) in mammals (Gilbert et al., 1998 ). Interestingly, and in contrast to other brain regions, there are neural stem cells in the dentate gyrus that are capable of differentiating into granule neurons that then integrate into the existing hippocampal circuitry. Animal studies have shown that spatial PS is impaired by selective destruction of hippocampal stem cells (Clelland et al., 2009 ) while spatial pattern processing is enhanced by manipulations such as exercise that stimulate neurogenesis (Creer et al., 2010 ; Sahay et al., 2011 ). The newly generated neurons receive sequential inputs from other granule neurons (transient), CA3 pyramidal neurons, cholinergic neurons in the basal forebrain and glutamatergic neurons in the entorhinal cortex (Vivar et al., 2012 ; Vivar and van Praag, 2013 ). Inputs from GABAergic interneurons increase gradually over a period of several months. Young granule neurons are critical for PS, whereas older granule neurons facilitate pattern completion (Nakashiba et al., 2012 ). Interestingly, spatial PS can be enhanced by exercise (running) in mice (Creer et al., 2010 ), and young adult humans perform better than older adults in spatial PS tests (Holden et al., 2012 ). As described in the next two paragraphs, the enhancement of PP by running likely played an adaptive role during human evolution, with the hypothesis being that individuals with superior hippocampus-dependent spatial pattern separation, which involves neurogenesis, would have a survival advantage because of the presumed importance of spatial pattern separation in remembering the location of objects in space and time (food sources, predators, etc.).

One prominent phenotypic change that is believed to have occurred during the evolutionary transition from the Genus Pan (chimpanzees) to the Genus Homo (approximately 5–8 million years ago), was the acquisition of an upright bipedal endurance/distance runner phenotype (Bramble and Lieberman, 2004 ; Lieberman and Bramble, 2007 ; Mattson, 2012 ). Bipedalism also enabled the evolution of the shoulder in ways that allowed humans to throw objects accurately at a high velocity, greatly improving their ability as hunters (Roach et al., 2013 ). This was also the period in the evolution of our species when the size of the cerebral cortex increased relatively rapidly, which suggests that the expansion of the territory covered by individuals and groups of humans (enabled by endurance running) played a role in the expansion of the cerebral cortex. Coverage of a larger territory during the great human expansion (Henn et al., 2012 ) would have provided the opportunity to access more resources (food, water, and shelter), and required a greater pattern processing capacity to remember details of the location and nature of the resources. Importantly, humans evolved the ability to transfer the information acquired and processed in their brains during their journeys to other individuals via gestures, map drawing, and language. Visual and auditory patterns were likely the most commonly processed and transferred because of the ability to readily and accurately reproduce sights and sounds. Accordingly, the regions of the brain that expanded in humans are mostly involved in pattern processing of sights and sounds, and their codification as written and spoken languages. Very interestingly, specialized motor training (sports) enhances language understanding by a mechanism involving recruitment of the left dorsal lateral premotor cortex, suggesting that the language system is functionally connected to motor skill-related areas outside of the core language networks (Beilock et al., 2008 ). The latter findings suggest that the language SPP capabilities of the human brain co-evolved with development of organized “teamwork,” which may have bolstered functional interactions between brain regions involved in language and those responsible for specialized sensory-motor skills.

How might endurance running have contributed to the SPP capabilities of humans? Among mammalian species there are significant positive correlations between brain size, cognitive abilities, and exercise capacity (Raichlen and Gordon, 2011 ). Studies of rodents, monkeys, and humans have shown that running can increase the size of several different brain regions including the hippocampus and midbrain (Rhyu et al., 2010 ; Erickson et al., 2011 ; Biedermann et al., 2012 ; Kolb et al., 2013 ). Presumably, individuals whose brains responded to endurance exercise by increasing the growth of their brain cells would have a survival advantage because of the superior PP ability conferred by the additional neural circuits. Indeed, at the cellular level running can increase numbers of synapses and the production of new neurons from progenitor cells in the hippocampus (Stranahan et al., 2009 ; van Praag, 2009 ). The ability of running to improve pattern processing is evolutionarily conserved, as demonstrated in experiments with rats and mice showing that running enhances hippocampus-dependent spatial pattern separation (Griffin et al., 2009 ; Creer et al., 2010 ). In humans, running improves mood and enhances cognitive and sensory—motor capabilities (Nabkasorn et al., 2006 ; Winter et al., 2007 ; Stroth et al., 2010 ), and running also enhances cognitive performance in monkeys (Rhyu et al., 2010 ). Interestingly, intermittent fasting (which simulates the natural condition of limited food availability encountered by our ancestors) can also enhance cognitive function and increase neuronal network complexity (Martin et al., 2008 ; Singh et al., 2012 ; Li et al., 2013 ). The latter findings are consistent with the possibility that individuals best able to enhance their cognitive function when faced with the challenge of food scarcity are most likely to find food and survive. The neurochemical processes that may link endurance running and fasting/hunger to heightened cognitive performance include the neurotransmitters glutamate, serotonin and norepinephrine and the neurotrophic factor brain-derived neurotrophic factor (BDNF), all of which are critically involved in the neuronal network plasticity required for pattern processing (Richter-Levin et al., 1995 ; Barkus et al., 2010 ; Rothman et al., 2012 ).

Intelligence involves not only the ability to encode large amounts of detailed pattern information, but also the ability to integrate that information and make appropriate (adaptive) decisions. Nerve cell circuits in the frontal cortex play a major role in decision-making in humans and lower mammals as well. Studies of patients who underwent neurosurgical removal of their hippocampus or frontal lobe on one side of their brain demonstrate that the neural circuits in these two brain regions mediate complementary aspects of SPP, namely, visual working memory (hippocampus), and programs of complex behaviors, decision-making and planning for the future (frontal cortex) (Owen et al., 1996 ; Barbey et al., 2009 ). Animal studies support the critical importance of the hippocampus, but not the medial prefrontal cortex (mPFC), in spatial pattern separation and further show the importance of both brain regions in working memory (McAllister et al., 2013 ). Because spatial pattern separation is a type of pattern processing that is conserved among all mammals, it is not considered SPP. However, while not sufficient to explain SPP capabilities of humans, spatial pattern separation is fundamental to the initial encoding of the patterns (letters, words, and other visual images) that are necessary for SPP (language, invention; imagination, mental time travel).

Iriki et al. (see Iriki and Sakura, 2008 for review) performed a fascinating set of studies in which they trained Japanese macaques to retrieve food located beyond their reach using a rake. This species of monkey does not use tools in the wild. Because evidence from human studies suggest that such body image-related tool using skills involve strengthening of synaptic connectivity in the parietal cortex, Iriki et al. performed electrophysiological recordings and positron emission tomography imaging studies of this brain region. They found that learning to use a rake was associated with an expansion of the functional representation (receptive fields) in the parietal cortex of the hand used to hold the rake. Using tract tracing methods, the authors found increased growth of axons and synaptogenesis in the intraparietal cortex of monkeys trained to use the rake tool compared to untrained monkeys. Based upon their findings in monkeys and studies of intellect in humans, the authors propose (Iriki and Sakura, 2008 ) that a major advance in human evolution was the process of “intentional niche construction” in which patterns encoded from prior experiences are used to construct new patterns that allow for prediction of the consequences of future actions within new niches/situations. This suggests that the mental manipulation of patterns to “rehearse” future scenarios is a capability of non-human primates, albeit dramatically less advanced than humans.

Emerging evidence, recently reviewed by Hunsaker and Kesner ( 2013 ), reveals that SPP occurs not only in the cerebral cortex, but also in other brain regions. Structures such as the striatum and cerebellum which are best known for their roles in the control motor function are also involved in episodic learning and memory, and decision-making processes. Neurons in the dorsal striatum are involved in procedural memory and also communicate with neurons in the ventral striatum which, in turn, integrate inputs from the hippocampus and prefrontal cortex to generate goal-directed behaviors (Pennartz et al., 2011 ). The cerebellum is critical for motor learning which involves the same kinds of synaptic modifications (e.g., glutamate receptor-mediated LTP and LTD) that underlie spatial learning encoded by hippocampal neurons (Gao et al., 2012 ). The learning of complex skills, such as those required to become adept at a sport, music or craft, involves neuronal networks that span a broad array of CNS structures (Schlaug, 2001 ). For example, fMRI was used to evaluate regional activities in the brains of shooters before and after 90 h of shooting training (Baeck et al., 2012 ). During mental imagery of shooting prior to or after shooting practice, the subjects exhibited activity in widely distributed regions of the cerebral cortex. However, the basal ganglia exhibited a distinct increase in activity only after shooting practice, suggesting that perfecting a shooting skill involves more focused neural correlates that may involve formation of new synapses. Electroencephalogram recordings of event-related brain potentials in adolescents with different amounts of musical training provided evidence that training improves the ability to detect sound patterns across longer time intervals (Wang et al., 2009 ). The latter findings are an example of experience-dependent expansion of pattern processing capability.

Functional modularity and a hierarchical “command and control” system provide important evolutionary frameworks for how the human brain works (Geary and Huffman, 2002 ; Barrett, 2012 ). The modularity model (Geary and Huffman, 2002 ) would predict that SPP functions of the human brain involve functional modules of neuronal circuits that include multiple brain regions working together to achieve their task (rapid decision making, insight, imagination, language, etc.). Studies of the connectivity of the prefrontal cortex with other brain regions provides strong evidence for such functional modularity (Passingham and Wise, 2012 ). Evolutionary considerations suggest that many neuronal circuits in the human brain are hierarchically organized with certain “design” features shared among different brain regions, while other design features are specific for, or tuned to, specific higher cortical functions (Barrett, 2012 ). The control of such trans-regional neural circuits likely involves a hierarchical mechanism in which a particular neuronal network plays a dominant, but not exclusive, role in a particular type of SPP.

Emotions reinforce pattern processing

“We have seen that the senses and intuitions, the various emotions and faculties, such as love, memory, attention, curiosity, imitation, reason, etc., of which man boasts, may be found in an incipient, or even sometimes well-developed condition, in the lower animals. “Charles Darwin, The Descent of Man .”

Emotions such as fear, anger, pleasure, and love are elevated states of arousal that enhance memory and recall of the events occurring during those emotional states (Bergado et al., 2011 ; Maren et al., 2013 ). This is a major, if not singular, function of emotions. Emotions evolved to reinforce memories of patterns of particular significance vis-à-vis survival and reproduction. Remembering the details of the events of an attack by a predator or intra-species rival will increase the probability of avoidance of such potentially deadly encounters in the future. Memories of the pleasurable experience of intercourse with fertile individuals of the opposite sex provides motivation for additional bouts of intercourse, and so increases the probability of passing one's genes on to future generations. Pattern processing in its most fundamental manifestation is enhanced by perception of the patterns in an emotional setting. Thus, hippocampus-dependent spatial pattern separation is enhanced when human subjects are shown fearful stimuli prior to testing pattern separation (Segal et al., 2012 ). Studies of animal models and human subjects have revealed core mechanisms by which the memory of an emotional experience is strengthened. The neural circuits and neurochemical substrates of emotion-related cognitive processing are conserved among mammals, and include brainstem, limbic and cortical networks, as well as neuroendocrine signaling. Brainstem noradrenergic neurons, limbic and cortical glutamatergic neurons, and neuropeptidergic neurons such as those producing corticotropin-releasing hormone (CRH) and oxytocin play prominent roles in emotion-related cognitive enhancement (van Stegeren, 2008 ; Thoeringer et al., 2012 ). Epinephrine and cortisol, adrenal hormones produced in response to activation of brain fear and anger pathways, also enhance memories of the patterns perceived during the emotional experience (Fitzsimons et al., 2013 ; Toth et al., 2013 ).

Humans have evolved as highly social animals (Chang et al., 2013 ) with close emotional ties to mates, offspring, parents and close friends that enhance their survival and reproductive success (Damasio and Carvalho, 2013 ). As with other emotions, those associated with social interactions may have evolved to enhance SPP. In this view, there is a self-amplifying reciprocal relationship between social interactions and SPP ability. Thus, advanced PP abilities enable the development of social bonds and networks and, conversely, social interactions stimulate SPP. Success in social interactions requires that one recognize others, remember their past experiences with those individuals, and communicate their intentions. Dunbar's social brain hypothesis of evolution of the primate brain includes the possible role of emotional attachments to mates and friends in complex social networks in the expansion of the cerebral cortex during anthropoid evolution (Dunbar, 2009 ; Sutcliffe et al., 2012 ). Because the memories of specific patterns (faces, places, conversations, etc.) can be reinforced or even embellished by emotions (Holland and Kensinger, 2010 ), it is reasonable to consider that evolution of the social brain was bolstered by emotional relationships. In addition to their use of complex language (see next Section), humans have added another dimension to social interactions—they are aware that others have thoughts and emotions very similar to their own. Humans therefore not only encode and process patterns representing their own experiences, but also the experiences of their family, friends and workmates. Social interactions require processing of information regarding the histories, behaviors and thoughts of many other individuals. Whether family members, employees or competitors, there are clear advantages to being able to know what others have done in the past, and to predict their future behaviors. Thus, inter-personal SPP is critical for success in most aspects of life, including acquiring and retaining friends, a job and a mate. Emotions reinforce inter-personal SPP, such that interactions involving anger, pleasure, sadness, etc. are retained, recalled and processed more thoroughly than interactions occurring in a neutral emotional context.

Languages as an advanced pattern encoding and transfer mechanism

Language is the quintessential example of the evolved SPP capabilities of the human brain as it involves (once learned) the instantaneous conversion of sounds to visual symbols, and vice-versa. Language is a complex behavior in which auditory and/or visual patterns learned from other individuals or perceived in the environment are encoded, processed and modified for the purpose of transfer of information to other individuals. Language involves the use of patterns (symbols, words, and sounds) to code for objects and events encountered either via direct experience or communication from other individuals. Language-related SPP can create new patterns (stories, paintings, songs, etc.) of “things” that may (reality) or may not (fiction) exist. Language-mediated encoding and transfer of auditory and visual patterns enabled the rapid evolution of the human brain and is likely a major reason for the current dominance of Homo sapiens . (Aboitiz et al., 2006 ; Berwick et al., 2013 ). Individuals with the ability to communicate to their family/tribe members the precise locations of food sources, hazards and other salient features of their environment would have had a clear survival advantage. In modern times, rapid advances in science, technology and medicine are facilitated by language-based information transfer. However, despite it being a remarkable leap forward in evolution, language may not involve any fundamentally new cellular or molecular mechanisms; instead, language is mediated by recently evolved neural circuits integrated with older circuits, all of which utilize generic pattern processing mechanisms. In this section I briefly summarize what is known of the evolutionary history of language, and then consider the underlying neural circuits and their highly efficient ability to detect, encode, manipulate, and then transfer patterns.

While birds and non-human primates exhibit auditory communication, their vocalizations convey general information such as danger, rather than detailed instructions. It has been proposed by Tomasello ( 2008 ) that the kinds of gestures used by great apes is an evolutionary precursor of language. Studies of infant humans further support the notion that pointing and gestures are an ontogenic precursor to language (Goldin-Meadow, 2007 ; Liszkowski et al., 2009 ). Languages involving complex vocabularies and written symbols and words are believed to have arisen in Homo sapiens beginning approximately 100,000 years ago (Berwick et al., 2013 ). The rapid evolution of language skills, and the underlying neural circuits that mediate language processes, is fully consistent with its fundamental role in the rapid advancement of human societies. Language provides powerful reproductive and survival advantages. A man who engages a woman in stimulating conversation is more likely to attract her as a mate than is an inarticulate man. An army whose soldiers use detailed maps and advanced communication skills is more likely to win a battle than is an army that charges forward “blindly.”

Language involves sensory and motor pathways, and associated cerebral cortical regions that encode and integrate the learned patterns of sounds and symbols/letters (Kuhl, 2010 ). Brain regions that are critically involved in language SPP in humans include ventrolateral prefrontal cortex and parietal cortex (Broca's area), and the posterior region of the superior temporal gyrus and adjacent parietal lobe (Wernicke's area) situated between the auditory and visual cortices. Broca's area is closely associated with motor cortex and, accordingly, is critical for the production of speech. Wernicke's area is critical for the comprehension of language and accurate communication via speech or writing. A comparison of human and macaque brains suggests there are two major “language pathways,” one that connects anterior auditory regions with ventrolateral prefrontal areas and one that connects auditory areas with ventrolateral prefrontal and parietal areas (Aboitiz, 2012 ). The second pathway is more highly developed for phonological and complex syntax processing, whereas in macaques it is involved more in hand and body gestures and involuntary vocalizations. Therefore, the elaborate vocal communication PP capability of humans has an evolutionary overlap with brain structures and circuits used for gesturing in non-human primates (Aboitiz, 2012 ). The neuronal circuits and mechanisms that evolved to enable communication using gestures are not well understood, but may involve a mirror system that matches observed events with similar intrinsically produced movements to enable communication of specific requests or intentions to another attentive individual (Rizzolatti and Arbib, 1998 ).

As they exist today, modern languages are the result of contributions of many generations of people living in the same territory/country. Once the basic set of symbols (letters) were established, specific patterns of the letters (words) were assigned to specific objects or phenomena, and the words were arranged in sequences to describe the temporal and/or physical relationships between the objects and phenomena. The number of words in the English language in common use (in a dictionary) is well over 200,000, but when one considers the number of discipline-specific words (in science, technology, engineering, etc.) the number of words is perhaps at least an order of magnitude greater. Moreover, for all intents and purposes there are an infinite number of sentences and stories that can be fabricated using even a small fraction of the total number of words. Remarkably, the learning of languages and the potentially infinite number of stories (word sequences) that an individual can construct are accomplished using a finite number of neurons that is established during early brain development. Our current understanding of the mechanisms of language learning, memory and communication is that they involve chemical and structural changes in synapses in neuronal circuits involved in encoding (hippocampus) and consolidation (multiple cortical regions) of words and the entities they represent (Shtyrov, 2012 ). Presumably, the synapses involved in language are “strengthened” by repetition (listening and talking, and reading and writing).

Drawings and maps

“The soul never thinks without a picture”—Aristotle

Drawings, including maps, date to at least 30,000 years ago (Valladas et al., 2001 ; Pike et al., 2012 ). Language and drawings serve complementary purposes. Language provided humans with a novel behavioral tool that strengthened a pre-existing ability to integrate both geometric and non-geometric information. Drawing of objects while they are being observed requires alternating observation of the object and drawing, a process with ongoing rapid feedback that allows (with practice) fairly accurate rendering of the objects' features. Drawings of real objects recalled from long-term memory are less accurate in detail but can provide key aspects of the object which the drawer wishes to convey to viewers of the drawing.

From an evolutionary perspective, maps may have been particularly important. According to Landau and Lakusta ( 2009 ): “Maps are the symbolic system par excellence for encoding and permanently retaining spatial information. Unlike language, the format of maps is roughly analog in nature, capturing the spatial layout of an environment by spatial transformations that preserve what is essential to finding things—most often, the geometric properties of layouts.” Maps are particularly valuable because they include large amounts of information about spatial relationships that cannot be readily conveyed via language. Cognitive maps of our environs are routinely constructed, stored, and refined. The maps can then be drawn and used by others to locate places they have never previously been. Grid and place cells in the hippocampus and grid cells in the entorhinal cortex are believed to play key roles in generating cognitive maps by the process of path integration. The parietal cortex and presubiculum, and probably additional connected brain regions, are also likely involved in the generation of cognitive maps. Because the precision of drawings based on cognitive maps is limited, particularly with regards to distances between objects/landmarks, humans have developed technologies to generate accurate maps drawn to scale. Indeed, the measurement and recording of distances have advanced to include modern day laser range finders and satellite-based global positioning systems.

Fabricated patterns: imagination, invention and magical thinking

“The same high mental faculties which first led man to believe in unseen spiritual agencies, then in fetishism, polytheism, and ultimately in monotheism, would infallibly lead him, as long as his reasoning powers remained poorly developed, to various strange superstitions and customs.… Yet it is well occasionally to reflect on these superstitions, for they show us what an infinite debt of gratitude we owe to the improvement of our reason, to science, and to our accumulated knowledge.” Charles Darwin, The Descent of Man .

While the ability to reproduce perceived patterns in drawings and maps is robust in humans, so too is the ability to create new patterns of entities that may or may not exist in the real world. To paraphrase Tattersall ( 2010 ) “the human brain has a superior ability to mentally manipulate animate and inanimate patterns into a myriad of intangible symbols that can then be recombined to produce new images of the world; we therefore live partly in worlds of our own mental creation, superimposed upon or distinct from the natural world.” Studies of the rapid eye movement (REM) (dreaming) state of sleep, and of various states of consciousness (see next two paragraphs), have provided insight into the neural networks involved in SPP that occurs in the brain in the absence of significant sensory inputs.

Functional MRI analyses of normal subjects in various states of consciousness (fully alert and engaged in behaviors, awake and resting, sleep states) and in anesthetized and brain-injured subjects have provided insight into where and how the brain processes patterns. When a healthy person lies quietly with their eyes closed for several minutes (the resting state) there is a network of neuronal circuits that are very active. This so-called default mode network (DMN) includes the mPFC, posterior cingulate cortex/precuneus (PCC), anterior cingulate cortex and parieto-temporal junction (Raichle and Snyder, 2007 ). A range of PP roles have been proposed for the DMN including introspection, social cognition, stimulus-independent thought, and integration of patterns/cognitive processes (Heine et al., 2012 ). For example, functional brain imaging studies suggest that the SPP capability of creativity is associated with strong functional coupling between the mPFC and PCC, two key nodes in the DMN (Takeuchi et al., 2012 ). The DMN activity and intra-DMN connectivity varies with consciousness state. For example, DMN activity in the PCC/precuneus is absent in brain dead patients, reduced in minimally conscious patients and further reduced in patients in a vegetative state (Vanhaudenhuyse et al., 2010 ). As subjects transit from the awake state to deep sleep there is reduced activity in the frontal DMN and reduced connectivity with posterior regions of the DMN (Horovitz et al., 2009 ). Patients in a minimally conscious state exhibit reduced connectivity within the DMN and between the precuneus and thalamus, and as the emerge from this state these connectivities increase (Fernández-Espejo et al., 2012 ).

The nature and function of sleep states has been a topic of considerable interest for centuries, with recent findings suggesting important adaptive functions that enhance brain function during wakefulness, most notably memory consolidation (Walker and Stickgold, 2004 ). Neural networks throughout the cerebral cortex are remarkably active during sleep (for review see Picchioni et al., 2013 ). In the REM stage of sleep there is increased activity in the hippocampus, cingulate and sensory cortices, and amygdala which may play roles in memory consolidation and regulation of emotions. Indeed, recall of dreams suggests that the PP occurring during REM sleep involves the mental construction of scenes that are often emotional in nature (e.g., a dangerous or disturbing situation). Based on recall of dreams, and emerging evidence regarding the neuronal circuits involved in dreaming, the types of SPP that occur during REM sleep in humans include language, imagination and magical thinking (De Gennaro et al., 2012 ). In non-REM light sleep there is a relative preservation of cortical network activities, while in deep (slow wave) sleep there is a marked decrease in activity of cortical networks. The DMN may play important roles in sleep states. During the transition to sleep activity among nodes within the DMN remains high, but interactions of the DMN with anti-correlated cortical networks is reduced. In deep sleep connectivity between the frontal and posterior nodes of the DMN is reduced. Until recently, studies of the DMN have been restricted to humans. However, a DMN that includes homologous brain regions has recently been described in rodents (Lu et al., 2012 ) which provides new opportunities to better understand the molecular and cellular workings of the DMN, and how dysfunction of the DMN contributes to aberrant PP and associated neurological disorders.

The importance of imagination and invention for the rapid advancement of the human species cannot be overstated. The invention of tools and technologies have dominated the recent development of civilizations throughout the world. The earliest evidence for the invention of tools by our human ancestors dates to approximately 2.5 million years ago in Ethiopia and Kenya where stones were fashioned into cutting tools (Plummer, 2004 ). At that time hominid brains were about the same size as those of apes (approximately 500 grams), whereas the brain of modern humans is nearly three times larger. Functional MRI studies suggest that when someone views and then imagines using a tool, widespread cortical neuronal networks are activated including those in the motor areas and temporoparietal, inferior frontal, occipital, parietal, and ventral temporal areas (Wadsworth and Kana, 2011 ). The latter findings are consistent with a scenario in which the ability to invent novel objects, technologies and computations likely required the expansion of circuits involved in the processing of patterns (particularly visual and auditory patterns) perceived in the environment or learned from others. Brain regions involved in episodic (chronologically ordered) memory of past events are also involved in the imagining of future events (Suddendorf et al., 2009 ). Thus, the neural substrates of imagination and invention enable the brain to formulate and construct tangible objects that provide future survival advantages to the individual, tribe or country. Examples include weapons, farming equipment and procedures, transportation vehicles (from horses to airplanes), drugs and medical devices, and sophisticated high-speed communication networks.

A fascinating aspect of human SPP is the ability to fabricate mental entities that do not exist in the real world, including magical thinking. Magical thinking can be defined as “beliefs that defy culturally accepted laws of causality. In Western culture magical thinking refers to beliefs in, among other things, clairvoyance, astrology, spirit influences, and telepathy.” (Einstein and Menzies, 2004 ). Superstitions and rituals are examples of types of magical thinking. The cognitive fabrication of imaginary patterns is prominently illustrated in religious beliefs which have presumably provided an adaptive advantage to many societies. Magical thinking is at the core of all major religions wherein specific life events are believed to be controlled by “God,” and the “believers” behavior is designed to please “God” and avoid “his” wrath (Bloom, 2012 ). Figure 3 illustrates how a type of SPP, magical thinking, has had a major influence on cultural evolution. A recent functional MRI study suggests that religious belief involves neural networks that process information regarding intent and emotion, abstract semantics and imagery (Kapogiannis et al., 2009a ). Transcranial magnetic stimulation focused on the left lateral temporal lobe, but not the right lateral temporal lobe or vertex, reduced magical thinking (Bell et al., 2007 ) providing further insight into the neural networks involved in magical thinking. Interestingly, structural differences between religious and non-religious subjects have been demonstrated including increased volume of right middle temporal cortex and reduced volumes of left precuneus and orbitofrontal cortex in religious subjects (Kapogiannis et al., 2009b ). These findings are consistent with psychological theories of the evolution of religious belief which posit adaptive cognitive functions of such magical thinking (Culotta, 2009 ).

Prominent historical examples of magical thinking, the belief in imaginary agencies, that became commonplace throughout the world, presumably because of its adaptive value for the individual and societies. (A) “Cain Fleeing from the Wrath of God” William Blake, British (1757–1827). The belief that one will be punished by an imagined “God” for immoral acts would be expected to reduce the incidence of such acts. Examples include behaviors that adversely affect monogamous relationships (adultery) or violent acts against other members of a society (murder). (B) “Saint valentine receives a rosary from the virgin” David Teniers III, Flemish, (1600s). The belief in a loving God and “angels” can facilitate cooperation and caring for others.

The history of “Gods” is that they are fabricated in the mind as explanations for phenomena that are not understood. Once those phenomena were explained by scientific investigation, those “Gods” were abandoned in due course. Take my Norse ancestors, for example, who fabricated Thor the “Thunder God” as an explanation for thunder storms. Nowadays most everyone accepts the fact that thunder storms are not caused by a “God,” but instead result from the rapid upward movement of moist warm air. In more recent history, the Gods of the major religions of the world (Christianity, Islam, Judaism..) are imagined to be “personal Gods” who can “answer prayers” heal the sick, and grant “eternal life” to those who follow “their” decrees. Of course the sacred texts that guide members of these religions were written by humans and contain fabricated tales of “creation,” “miracles” and “wrath” of God. Magical thinking may have resulted in the belief by many religions that humans are fundamentally different from other organisms, invoking their possession of a “soul” apart from the brain itself and believing themselves “created in God's image.” However, advances in knowledge of the molecular and cellular underpinnings of brain function during the past 50 years strongly suggest that Gods and an afterlife are delusions fabricated within and confined to neural networks of the human brain (Dawkins, 2006 ). Nevertheless, many dogmatically religious people continue to ignore the incontrovertible evidence for human evolution, and instead embrace the mythology of creation by a God (Coyne, 2012 ). This is a fascinating example in which a type of uniquely human SPP (magical thinking) has sustained a belief that is based on fantasy rather than reality.

Interestingly, as described in the next section, there is fine line between the magical thinking of religious beliefs that have provided adaptive value for many civilizations and societies, and the delusions of psychoses that can place individuals and those they associate with in harm's way. This notion is illustrated in the following two quotes which exhibit the remarkable similarities between the delusions of individuals with schizophrenia and those described in religious doctrine. “Because you think what you're believing is true,” she replied. “I used to know, beyond a shadow of a doubt, that—what other people would think was crazy—I thought was absolutely true, that I was privy to a special truth.” Elyn Saks, Professor and schizophrenia patient . “You have searched me, Lord, and you know me. You know when I sit and when I rise; you perceive my thoughts from afar. You discern my going out and my lying down; you are familiar with all my ways.” Bible NIV, Psalm 139, verses 1-3 .

An understanding of the neurochemistry of delusions has emerged, in part, from studies of psychedelic drugs such as mescaline, LSD and psilocybin which often elicit mystical/spiritual experiences and magical thinking (Griffiths et al., 2011 ; Lyvers and Meester, 2012 ). Research on these drugs has revealed aspects of SPP in the human brain that are shared with lower mammals. First, the serotonin 5-HT(2A) receptor, which is conserved among mammals, is believed to be the molecular target of all three psychedelic drugs. Second, rodents exhibit behavioral responses to the psychedelic drugs consistent with altered perceptions/PP similar to humans including reduced impulsivity and altered time perception (Hanks and González-Maeso, 2013 ). Of course many people come to believe in imaginary agents/Gods (Christians and Muslims) or the “feeling of oneness” (Buddhism) not by taking psychedelics, but instead by indoctrination at an early age, with regular reinforcement with prayer and meditation. Interestingly, differences in serotonin receptor ligand binding between those who are and are not self-transcendent/religious have been reported (Borg et al., 2003 ). It will be of considerable interest to elucidate the SPP mechanisms (neural circuits and neurochemistry) that mediate reality-based thinking and magical thinking, and the transitions between these mental states.

Aberrant pattern processing in psychiatric and degenerative brain disorders

The burden of brain disorders on societies is immense. Anxiety disorders and depression hobble the lives of hundreds of millions of people throughout the world (Baxter et al., 2014 ). Although effective treatments are available for many people affected with these disorders, many others continue to suffer. Less common, but more refractory to successful treatment, are bipolar disorder and schizophrenia (Saarni et al., 2010 ). Because psychiatric disorders often have an early age of onset (second, third and fourth decades of life) and can exhibit a relapsing and remitting course, their lifetime burden is substantial. Later in life many people develop a neurodegenerative disorder, with Alzheimer's disease (AD) and Parkinson's disease (PD) being the most prevalent (Chen, 2010 ; Reitz and Mayeux, 2014 ). AD and PD are progressive fatal disorders with the patients requiring constant care for 5–10 years. Here I consider the roles of aberrant and/or impaired PP in the pathogenesis of these neurological disorders.

In general, psychiatric disorders result from an abnormal skewing of SPP in ways that dissolve the neural circuit-based boundaries between reality and imagination, between the realms of possibilities and probabilities. There are likely evolution-based reasons that anxiety and depression, and “paranoia spectrum disorders” are so common. Everyone experiences anxiety transiently in situations that involve real threats to oneself or loved ones; this heightened state of arousal is an adaptive response that provides motivation toward actions that can mitigate the danger. However, individuals with an anxiety disorder react to perceived threats that either do not in fact exist or are highly unlikely to occur. Depression is a state of self-doubt and hopelessness that often follows a period of chronic anxiety or a catastrophic life event. It involves a pervasive distortion of reality and an unrealistic catastrophic view of the future. During their daily experiences individuals with chronic anxiety and depression perseverate on patterns of “worst case scenarios.” For example, a minor reprimand for an error made at work may be mentally magnified into a pervasive rumination on a scenario in which the person is fired and can no longer support his/her family, etc. Central to the perturbed thought processes in these disorders is the complex SPP repertoire of humans including language and imagination. The cellular and molecular alterations underlying anxiety disorders and depression are partially understood, and involve reductions in synaptic densities in the hippocampus, deficits in serotonergic and noradrenergic neurotransmission, and reduced BDNF signaling (McEwen et al., 2012 ; Blier and El Mansari, 2013 ). Accordingly, treatments that stimulate BDNF signaling, including exercise, serotonin/norepinephrine reuptake inhibitors and electroconvulsive shock therapy are effective in many patients (Domingos da Silveira da Luz et al., 2013 ; Duric and Duman, 2013 ). Studies of animal models have clearly shown that BDNF plays a major role in spatial pattern separation, and that interventions known to elevated BDNF levels and ameliorate anxiety and depression enhance spatial pattern separation (Creer et al., 2010 ; Bekinschtein et al., 2013 ). These findings suggest roles for impaired PP in the pathogenesis of anxiety disorders and depression.

Based upon reciprocal social interactions, language-based communication and the perception of others' emotions, in light of their own introspective thoughts and emotions, humans presume that others have a mind similar to their own. By envisioning future interactions with other individuals, the outcomes of those future interactions can be biased in one's favor. Similarly, the ability to predict the thought processes and actions of others provides major advantages in navigating what are often complex social landscapes in human societies. However, the inferring of agency, beliefs and intentions in others, is dysregulated in schizophrenia, bipolar disorder and autism spectrum disorders (Senju, 2012 ; Martin et al., 2014 ). The diagnosis of schizophrenia is based on a person suffering from delusions, hallucinations and disorganized speech, often accompanied by or oscillating with negative symptoms such as anhedonia, social isolation, and lack of motivation. A key feature of schizophrenia is a blurring of the lines between external reality and internal imagination, between patterns that are real and those that are mentally fabricated (Larøi et al., 2012 ; Howes and Murray, 2014 ). The hallucinations and paranoia that occur schizophrenia patients could be considered a pathological dysregulation of the imagination and mental time travel categories of SPP.

In schizophrenia, patterns generated within the brain are perceived as external. At other times, schizophrenia patients may experience paranoia, an unrealistic belief that others intend to harm them, and a fear of persecution. Such delusions can severely compromise the ability of schizophrenics to perform well in school, a job and social settings. However, more subtle paranoid beliefs are common among the general population, and may often be beneficial. For example, when returning to one's car in a dark parking lot, the belief that there may be a robber lurking in the vicinity will prompt behaviors that reduce the chance of being mugged. Similarly, not providing personal information to strangers can prevent identity theft. For most high-functioning individuals in modern society there is a balance between trust and paranoia, based upon a rationale appraisal of the situation based upon experience and understanding (Green and Phillips, 2004 ; Nelson et al., 2012 ). It has been proposed that religion and schizophrenia have similar evolutionary underpinnings (Dein and Littlewood, 2011 ). In this view, both theory of mind and attributing life events to an external agency are hyperextended and intrude thought processes and actions excessively. One way to view the brains of those who believe in a God, particularly fundamentalists, is that they have a low level of trust in people and so fabricate an external agency, a security blanket in which they trust.

It can be argued that although their symptoms are different, human psychiatric disorders all involve distortions of reality (hallucinations in schizophrenia; unrealistic view of threats to well-being in anxiety and obsessive-compulsive disorders; and a distorted image of one's current and future life situations in depression). In essence, the SPP capabilities of imagination and envisioning future scenarios are dysregulated. Interestingly, structural and/or neurochemical abnormalities in the prefrontal cortex have been implicated in each of the major psychiatric disorders (Huey et al., 2008 ; Rigucci et al., 2010 ; Teffer and Semendeferi, 2012 ), again highlighting the importance of the evolved human prefrontal cortex in both normal and pathological aspects of SPP.

Alzheimer's disease (AD) is rapidly becoming a major cause of morbidity and mortality as an increasing number of people live into their 70 and 80 s, the most common age of disease onset (Mayeux and Stern, 2012 ; Chan et al., 2013 ). AD is characterized by the progressive deterioration of cognitive function with an insidious impairment of short-term memory that becomes amplified to the point of inability to perform even the simplest tasks. As synapses and neurons degenerate in the hippocampus and connected regions of cerebral cortex PP ability is lost. One of the cognitive tests routinely used in the diagnosis and evaluation of disease progression in AD is the clock drawing test in which the subject is asked to draw a clock that includes the hour numbers 1–12 and shows a specific time. Figure 4 shows examples of a clock drawing test when a subject progresses from normal brain function to mild cognitive impairment (MCI) or early AD to advanced AD. This example of progressive deterioration of clock drawing ability in AD illustrates how the degeneration of brain regions involved in SPP can manifest as an all too common human brain disorder. Aging is the major risk factor for AD. During normal aging there is often a decrement in spatial pattern separation performance (Stark et al., 2010 ) which may contribute to age-related episodic memory deficits (Holden and Gilbert, 2012 ). Many individuals may compensate for such age-related alterations, and some cases of AD may result from a failure of such adaptive neuroplasticity (Buckner, 2004 ).

The progressive deterioration of pattern processing ability in a subject as they progress from mild cognitive impairment (MCI) to severe Alzheimer's disease (AD) . In this clock drawing task the subject is asked to draw a clock with the hours and showing the time 2:30. When the person has MCI/early AD the numbers for the hours on the clock are drawn in proper order, but during the time it took to draw the clock the subject forgot that he/she had been asked to show the time 2:30. In the case of the patient with late-stage AD, the drawing bears little resemblance to a clock.

Predictions of the SPP theory of human brain evolution

If SPP has played a fundamental role in the evolution of the human brain, then this should be evident in both the historical record and trajectories of different human populations throughout the world. The SPP theory predicts that populations that more rapidly develop SPP capabilities will experience accelerated accrual of resources and prosperity. The examples of major SPP abilities acquired during human evolution that were considered above (language, invention, imagination, reasoning, and planning for the future) should have each provided a survival and resource-accumulating advantage. The SPP theory therefore predicts that populations that did not develop each of these SPP capabilities would have been outcompeted by those populations with brains that did acquire, through evolution, those SPP capabilities. This prediction is supported by the fact that all surviving populations of H. sapiens use language, invent tools and exhibit imagination and complex reasoning. Hominin populations lacking, or with relatively poorer, SPP capabilities presumably failed to compete successfully, and so no longer exist.

The numbers of extinct hominin species is uncertain, estimates range from 8 to 27, with evidence suggesting that Neanderthal and Denisova hominins extinctions were driven by H. Sapiens , the only surviving species (Bokma et al., 2012 ). The pattern processing capabilities of our most recent ancestral species cannot be fully established, but did include the invention/use of simple tools, drawing skills, and some forms of gesture-based and verbal communications. One prediction of the SPP hypothesis is that the development of qualitatively and/or quantitatively new pattern processing capabilities conferred a survival advantage to H. Sapiens . Brain size deduced from cranial vault volume varies among now extinct hominins, with most considerably smaller than humans and some, notably Neanderthals, close to H. Sapiens (Arsuaga et al., 2014 ). As described above the expansion of the prefrontal cortex and brain regions associated with processing of visual input in humans relative to great apes, suggests that the functional roles of these brain regions likely provide major adaptive advantages. A prediction of the SPP theory is that there was a progressive increase in the size and synaptic/functional capabilities of these brain regions as hominin species evolved. Unfortunately, the latter prediction is not directly testable given the lack of brain specimens from any extinct hominin species.

The SPP theory predicts that variability in SPP capabilities among current human populations will be associated with variations in resources, health and welfare (indicators of fitness) of the different populations. Studies have documented positive associations of brain size with greater intelligence, faster decision making and greater cultural achievements between and within genetically differentiated populations of modern humans (Rushton and Jensen, 2008 ). This suggests that variability in SPP among existing groups of humans may be sufficiently robust to influence their relative fitness and so the future evolution of the human brain. The differential SPP-mediated development of technologies to improve transportation, manufacturing, scientific discovery and health care have resulted in the advancement of some populations above others. Individuals in populations that have most heavily utilized the SPP capabilities of their brains currently enjoy the greatest levels of prosperity, better health and longer lives. The disparities between and within countries are in some cases quite striking, with African countries exhibiting considerably less propensity for SPP, as reflected in poverty, low levels of education, high infant mortality and short lifespans. In contrast, the United States, and many countries in Europe and Asia are experiencing economic growth that is arguably resulting, in large part, from development of SPP-based technologies, with computer-based systems being a prominent example of a human invention that enables processing of information at rates many orders of magnitude beyond the capability of the human brain. Clearly, humans have recognized the central importance of SPP for their advancement as a species.

Interestingly, although variability in DNA sequences is the fundamental molecular basis of evolution, emerging evidence suggests major roles for trans-generational epigenetic mechanisms for the rapid inheritance of traits. For example, changes in DNA methylation can occur in response to life experiences, and such methylation changes can affect gene expression and phenotypes influenced by those genes. The brain may be particularly modifiable by epigenetic processes that can influence its development, function and susceptibility to behavioral disorders (Meloni, 2014 ). Animal studies have shown that changes in DNA methylation that occur in brain cells in response to socio-environmental factors (particularly during early life) play important roles in learning and memory and, importantly, can be transferred from parents to offspring. This has been shown for several behavioral traits in animals including sociality, and susceptibility to addiction or depression (Meloni, 2014 ; Sen, 2014 ; Vassoler and Sadri-Vakili, 2014 ). If epigenetic mechanisms influence SPP, then it would be predicted that SPP capabilities may be rapidly enhanced within only a few generations.

Finally, the SPP theory predicts that human evolution will continue to involve expansion of the prefrontal cortex and functionally associated brain regions, with resulting improvements in the brain's ability to rapidly process information and make (good) decisions. The specific outcomes of advanced SPP for future generations remain to be determined, but may (hopefully) include the invention of technologies that eliminate suffering and help ensure the long-term survival of our species.

Societal implications

This closing section is intended to highlight the importance for society of advancing an understanding of how and why SPP is fundamental to the human experience. To illustrate this point, examples are provided of how SPP has enabled the development of major human cultural practices that are not based in reality.

Considerable evidence, some of which is described above, supports the notion that SPP is the underlying mechanism for many higher cognitive functions of humans (thought, reasoning, imagination, invention). This suggests that humans are the dominant species, in part, because of the superior ability of their brains to store and process patterns and transfer those patterns to others. Technologies developed by the human brain are based on the reproduction and modification of patterns encountered in nature (e.g., airplanes designed around birds), and/or fabrication of new patterns (e.g., the computer I am using to write this article). While the centrality of SPP to all of human consciousness, thoughts and behaviors is congruent with our evolutionary history, some neuroscientists and most of the lay public are unaware of this important fact. For example, in an interesting discourse on how “our minds make inferences that appear to go far beyond the data available,” Tenenbaum et al. ( 2011 ) do not consider advanced PP as the answer to this question and, instead, conclude that “Deeper is a framework for understanding why the mind works the way it does, in terms of rational inference adapted to the structure of real-world environments, and what the mind knows about the world, in terms of abstract schemas and intuitive theories revealed only indirectly through how they constrain generalizations.” For the reasons described in the preceding sections, SPP mediated by brain regions expanded in humans (PFC, in particular) may underlie the ability of humans to make intuitive and rational inferences.

Knowledge of the roles of SPP in human brain function could be incorporated into the primary education so that everyone has a basic understanding of the mechanisms underlying human cognition, creativity and complex behaviors. The ability to distinguish reality from fantasy is one example where education is lacking such that a considerable portion of the human population is unaware of the fact that supernatural entities such as Gods are fabricated within the human brain, and that belief in such mentally fabricated entities is learned from other “believers.” While the percentage of Americans who believe in God is slowly declining, and those that believe in evolution is increasing, recent polls indicate that approximately 75% continue to believe in the actual existence of a “God” or “universal spirit” (Galanter, 2010 ; Harris Poll, 2013 1 ). Indeed, many individuals in positions of authority espouse an external “God” as their guiding “force.” For example, a recent President of the United States stated in a public speech that “I am driven with a mission from God. God would tell me, ‘George go and fight these terrorists in Afghanistan.’ And I did. And then God would tell me ‘George, go and end the tyranny in Iraq.’ And I did.” George W. Bush. August, 2003. Sharm el-Sheikh . This type of delusional SPP has been a justification for violence for millennia and, indeed, is the justification used by the Islamic extremists who chanted “Allâhu Akbar” (God is great) as they crashed airplanes into the World Trade Center buildings on September 11, 2001 (McTernan, 2003 ). Another example comes from the geneticist and current director of the National Institutes of Health who wrote: “God's domain is in the spiritual world, a realm not possible to explore with the tools and language of science. It must be examined with the heart, the mind, and the soul—and the mind must find a way to embrace both realms.” Francis S. Collins, The Language of God ( 2006 ). On the contrary, from the perspectives of neuroscience, realism and moralism, it is important for the advancement of modern societies that children not continue to be deceived into “embracing both realms,” and instead be taught to distinguish reality from fantasy, and to embrace reality and enjoy fantasy. The mental fabrication of “spiritual worlds” can certainly be comforting, and the pursuit of valuable aspects of the major religions such as morality and the principles of “oneness” and caring for one another should continue, albeit with the knowledge of their evolutionarily conserved neural substrates.

Compared to lower species, the human brain is particularly advanced in its ability to fabricate new patterns and transfer them to others. This SPP ability has been fundamental to the development of new technologies and to the dissemination of knowledge of the world and its societies. What are the implications of SPP being the neural basis for the entire human experience for the future of human societies? Computers can now perform many types of pattern processing and are increasingly used to replace people in positions such as accounting, data processing and manufacturing. While computers still fall considerably short of humans in the realms of invention and scientific discovery, one might imagine that as understanding of the mechanisms by which neural circuits in the human brain process patterns increases, computers and robots may equal or even surpass humans in the areas of creativity, invention and even scientific discovery (Sparkes et al., 2010 ). Artificial intelligence is an active area of investigation involving efforts to mimic the brain's SPP capabilities on the one hand, and to interface the brain with machines, on the other hand (Meltzoff et al., 2009 ; Fingelkurts et al., 2012 ). A better understanding of SPP mechanisms, at the molecular, cellular, neuronal network and behavioral levels will not only advance knowledge of brain function and neurological disorders, but may also inform research in wide range of fields of technology.

Conflict of interest statement

The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Acknowledgments

This work was supported by the Intramural Research Program of the National Institute on Aging, NIH.

1 http://www.harrisinteractive.com/NewsRoom/HarrisPolls/tabid/447/ctl/ReadCustom%20Default/mid/1508/ArticleId/1353/Default.aspx

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