Autism Theory 25 Years in the Making

Summary: New autism theory is consistent with the current science on the genetics of the disorder but shifts the focus to the positive traits of ASD and historical events that altered the prevalence of autism in society.

Source: Vanderbilt University

A unifying explanation of the cause of autism and the reason for its rising prevalence has eluded scientists for decades, but a theoretical model published in the journal Medical Hypotheses describes the cause as a combination of socially valued traits, common in autism, and any number of co-occurring disabilities.

T.A. Meridian McDonald, PhD, a research instructor in Neurology at Vanderbilt University Medical Center, has spent 25 years researching autism, from a time she could read literally every research paper on the topic in the 1990s until now, when there is an overload of such studies.

“Up until now there have been a lot of theories about the possible causes of autism but none of those theories account for the majority of autism cases,” McDonald said. “There are also a lot of theories as to why the prevalence of autism has been increasing in the population but, to date, there hasn’t been a theory that provides an explanatory model that accounts for all of those phenomena, including the genetics, social history, or characteristics of autism.”

The CDC estimates that 1-in-54 persons are on the autism spectrum.

Consistent with Genetics Research in Autism

McDonald’s theory, titled ‘The Broader Autism Phenotype Constellation-Disability Matrix Paradigm (BAPCO-DMAP) Theory,’ is consistent with the current science on the genetics of autism but shifts the focus to positive traits of autism and to historical events that changed the prevalence of autism in society.

“The BAPCO-DMAP theory describes how people are attracted to other people who are very similar. They are attracted to certain traits that are very common in the population, and this leads to offspring who are more likely to have certain traits, as well as a greater intensity of traits.” McDonald said.

“The (BAPCO) traits are not what people expect. They expect the traits to be about challenges or difficulties, but instead there are six main traits — increased attention, increased memory, a preference for the object world vs. the social world and their environment, increased nonconformity, increased differences in sensory and perception, as well as systemizing.”

BAPCO Can Interact with Development

BAPCO traits alone are not necessarily disabling. A person can have BAPCO traits and still have excellent communication and socialization skills, but too much of any of these traits can affect development.

For example, although it seems counterintuitive, McDonald outlines how increased memory and attention can delay language development in children with BAPCO traits.

“Typical babies have tiny attention spans and working memory. These limitations on memory and attention actually help babies learn their first language by breaking the words into their tiniest parts,” she said.

“But an infant with very high levels of attention and memory has a harder time with learning language because they are unable to break the language down to very small parts, so they learn groups of sounds instead.”

McDonald describes how increased memory and attention can lead to echolalia, where children speak in, or repeat, long phrases without seeming to understand them.

“You can often see children with autism engaging in sense-making activities, such as watching the same show over and over and memorizing information,” she said.

BAPCO Can Interact with Disabilities

BAPCO traits can also interact with disabilities. If a person has BAPCO traits and they also have a disability such as Down syndrome or information processing disorder, then those things combined can create greater challenges than what would be experienced by an individual who has only a BAPCO personality or a disability, but not both.

Increased Prevalence of BAPCO and Autism

McDonald’s theory also highlights how the prevalence of autism has increased in higher income countries due to societal changes that increase freedoms in education, employment and other opportunities for both men and women.

In societies where people do not have freedom to pursue their interests and passions, where meritorious education is not valued, where men and women do not have freedom to choose their careers, and where nonconformity is not tolerated, McDonald predicts the frequency of BAPCO traits in these populations will be very low.

This shows a child playing with colorful building blocks
A person can have BAPCO traits and still have excellent communication and socialization skills, but too much of any of these traits can affect development. Image is in the public domain

“The frequency and intensity of BAPCO traits in the U.S. have increased, for example, because individuals are more likely to meet and have children with other individuals with similar education, occupations and interests than would have been possible 100 years ago,” she said.

“When men and women with BAPCO traits have children it can increase both the frequency and intensity of BAPCO traits in the population.”

No Cure for Autism

McDonald said she now knows what causes autism but it is not something that could be cured and, honestly, she wouldn’t want to do that.

“What we call ‘autism’ is the BAPCO personality combined with a disability or very intense BAPCO traits,” she said. “Because the BAPCO is made of socially valued traits, it is not possible to cure autism. Instead, we need to focus on the full range of disabilities that affect people with and without the BAPCO personality.”

McDonald said future research should focus on the causes and treatment of underlying disabilities and also on providing supports such as interventions for individuals with disabilities, including those who have this combination of BAPCO and disability intersection.

“When we talk about autism we need to address the developmental disabilities that these individuals are experiencing but also find way to support and enhance their broader autism trait constellations,” she said.

About this autism research news

Source: Vanderbilt University
Contact: Craig Boerner – Vanderbilt University
Image: The image is in the public domain

Original Research: Closed access.
The broader autism phenotype constellations–disability matrix paradigm: Theoretical model for autism and the broader autism phenotype” by T.A. Meridian McDonald. Medical Hypotheses


The broader autism phenotype constellations–disability matrix paradigm: Theoretical model for autism and the broader autism phenotype

The prevalence of autism has increased dramatically over the last 60 years, and the cause of this increase is unclear. In this paradigm-shift paper, I propose an explanatory paradigm for the cause of autism and its increased prevalence in the general population. I also discuss how social and historical contexts may have influenced the evolution and manifestation of specific traits in the autism population. These traits expand the characterization of the broader autism phenotype to include a constellation of socially valued traits, termed Broader Autism Phenotype Constellations (BAPCO). The frequency of these traits may have increased due to assortative mating opportunities that occurred alongside social changes in education and occupational opportunities over the last 100 years. I propose that assortative mating can lead to both positive and negative developmental consequences affecting social and language development. I also propose that BAPCO traits, which are not intrinsically disabilities, could interact with co-occurring conditions in a new model called the BAPCO-Disability Matrix Paradigm (BAPCO-DMAP). In this paradigm, autism is located at the intersection of BAPCO traits and at least one co-occurring condition. These proposed models support the need to create a more comprehensive definition of autism that includes constellations of BAPCO traits. The BAPCO-DMAP paves the way to testable predictions of autism prevalence and provides a framework to better understand the foundational traits of autism. Finally, this paradigm radically redefines the broader autism phenotype with characteristics that can inform therapy and child development.

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  1. This is by far the dumbest article I’ve ever read. I feel like I’ve just been pranked?

  2. Why must certain differing opinions be presented so viciously and in such a demeaning manner? We are all learning as we go. Closed-minded attacks and humiliating rebuttals do not help. All research and opinions should be considered to form a full and accurate picture.

  3. Good grief… have you not read anything on the gut brain interaction ever? Science is littered with it, every time I search scientific articles there is more info… articles like this only serve to rationalise personal inaction and surrender to the mythical concept of Fate. It sounds as if you want to disempower people.

  4. Aren’t Autism and Asperger’s part of what used to be called mental retardation, which was also a “spectrum” of disabilities and seems no longer to be used as a term or definition (which is a GOOD thing, because it seems to keep people from making snap/negative decisions or forming opinions about a person and enables much more research to go forward, instead of pigeonholing people into what would essentially be non-treatment)? If this is NOT the case, then where have all the retarded children/people gone?

  5. My autistic son just turned 50. His cause is the cause of many with that syndrome. He was the product of a natural child birth that took 12 hours when the possibility of a surgical delivery was not present. The extended birth trauma caused a lack of O2 to the brain for some time causing permanent damage. His ability to cope with part of a functioning brain has been his disability. To this day, he speaks almost not at all, but can write and spell with the best. He displays many of the traits associated with the syndrome.
    When children are given vaccines, they may have an allergic reaction which is severe. That reaction may not be recognized by the care giver, as an unconscience child is a sleeping child and not needing attention. If the child does not come out of the coma, it is called SIDS, and dismissed. If it does, it may have autism as part of the brain was killed during the time of comatose reaction.
    Since children are rarely diagnosed with autism until they are over 25 mos. old, such connection is not established in most cases.
    To avoid the above, surgical deliveries should be the norm where the prospects of a natural delivery are in jeopardy. Also, when giving infants and toddlers vaccinations, they should be observed closely for 6 hours minimum.
    Larry FOSGATE

  6. Yes, this reports misses out diet. Diet can make a difference to negative symptoms. Autistic children often have physical health issues too. The positive aspects of autism are welcomed, but they tend to die earlier.

  7. I have never read such an unscientific and ridiculous article.
    Autism is a hyperactive fear response to sensory stimuli. An overactive amygdala with a fear response that is hard to extinguish.
    This interferes with forming strong connections in the prefrontal cortex and has a weakened corpus callosum.
    That is the science.
    Look it up.
    This is a result of inflammation and toxicity.

    Yes you can treat and cure autism if you understand the root mechanisms.
    Exposure therapy and attention/ affection. To ameliorate the fear response.

    Uninformed babble

    1. Did you read the paper, or are you running a naturopathy grift on Facebook called “Family Focus Autism Center” whose ability to do business without criminal liability requires that you NOT EVER read this paper?

      1. I am not grifting as you call it.
        I make no money whatsoever.
        I freely offer my knowledge of independent research that I have been accumulating for over twenty years.
        I base my recommendations on science, experience and common sense.

    2. Thank you Carri – Your comment helps me to hang on when I just want to throw up my hands.

      When I attempt to explain such realities to people who have the wrong belief due to misinformation I invariably get the dismissive response that “it’s just too complicated for anyone to really understand” usually summed up as “you can’t know, nobody can really know”. This is just hog wash. As a lifelong autodidact I am always amazed by how much data can easily be accessed and digested, winnowing out the truth of an issue, or at least as close as one can. Even easier than discerning truth is how incredibly easy it is to disprove the lies and misinformation.

      Most people are not looking for the truth, they are looking for confirmation of their existing beliefs. Critical thought is no longer prevalent in society and is in fact discouraged.

      1. Jeff
        Thank you for the encouraging comment.
        Too true that most people don’t like to have their beliefs challenged.
        I actually enjoy it because it makes me examine and defend my position.
        I find I grow more and learn more when challenged.
        So it is good for me.

    3. Thank you. Don’t dismiss the possibility of increasing ambient microwave radiation from wireless communication devices on embryo logical development though.

  8. Another rather useless paper/research.
    First — diagnose ‘Autism’ properly, rather than from a grab bag of symptoms. This
    diagnosis is simply a description.

    There are many many different behaviours, mental problems and social problems with many many different causes.
    Then just because a certain personality type is different from the major (normal in statistical terms) does not a handicap maketh. Some or the greatest inventors. scientist, writers and artists would have need called “Asperger’s” if they were alive today. By and large their behavior is NOT dysfunctional. In fact, to many of us, ‘normal’ behaviour seems far more dysfunctional!
    But them ‘
    Autism also includes people who are totally unable to care for themselves, people whose behavior is dangerous or disruptive in public, or seems to mostly stem for low intelligence or serious brain damage.

    1. Bravo Jenny
      Yes this kind of stuff just interferes with actually helping autistic individual.
      No science all supposition
      Happy to see you comment

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