Neurotypical babies' social behavior takes off as their attention to social input plummets: Why we should be wary of autism theories based on attention to people vs. objects

During the second half of the first year, usually around nine months, most babies learn to share attention with others by alternating their gaze between another person and an object. Their repertoire of social gestures expands enormously, too. With such a rapid spurt of social development, typically developing babies must be paying more attention to people and less attention to other things in their environment, right?

As it turns out, when you measure what babies are actually looking at, the opposite is true.

Babies' visual environments
There are lots of theories about what babies learn from their environment, how much they can learn from the environment, and how much must be present innately. For example, is the language babies hear complex and varied enough to allow them to figure out the grammatical rules of language? Or, is an innate grammar-understanding part of the brain necessary to explain it (a "poverty of the stimulus" argument)?  Do babies need lots of exposure to faces to learn to recognize them, or are they just born with a specific part of the brain that processes faces in a unique way that supports recognition? These issues are easy to speculate about, but hard to actually test: you need a way to measure what babies see and hear in their homes and communities. And until recently, this was very hard to do.

One particularly important aspect of babies' environments is the other people they see, particularly their faces. Faces are a particularly important part of the visual environment because they are vital for recognizing others, contain emotional and social information, and convey cues that are helpful for language perception (e.g., mouth movements). So, Swapnaa Jayaraman, Caitlin Fausey, and Linda Smith [1] wanted to measure the faces babies saw during their first year, at home and in the community. How often did they see faces? Whose faces did they see? How close up were they, and what parts were visible? Did these variables change as babies grew?

They measured the faces babies saw using small head cameras mounted on top of a hat, which babies wore1. The cameras showed a broad view of whatever was directly in front of the child's head. Parents were shown how to use the camera and asked to try to capture 4-6 hours of video during a variety of daily activities while the baby was awake and alert. They were given up to two weeks to make the recordings.

Left: A baby sits in a toy-covered baby seat at home, wearing a blue soft hat with a head camera on top. Right: Examples of three 5-second frames recorded by the head camera, showing a woman spooning out food and bringing it towards the baby. Her head takes up a large percentage of the frame.
Above: a) A baby at home, wearing the head camera mounted on a hat. b) Example frames coded during data analysis.
From Jayaraman, Fausey & Smith (2015).

Families of 22 babies ranging from 1 to 11 months old participated, providing over 100 hours. Most of the recordings were in the child's home (84%), but some took place outdoors or in group settings (11%), in the car (4%), or other locations (2%), such as during errands. From this data, one still frame per five seconds of video was coded (a total of 72,150 frames).  Coders looked for the following:

  1. Is there a face, or part of a face, in the frame?
  2. Whose face is in the image?
  3. Estimated distance of the face from the head camera.  This estimate was made by comparing the face or face parts in the frame with templates created by filming a female face at increments of 1 foot (1 foot, 2 feet, etc.) from the camera.
  4. Are both eyes visible?

Smith's team wanted to know how many faces babies saw, to determine how much experience they actually had looking at faces. They also wanted to know how close-up and clear the faces would be, because quality might matter as well as quantity. Further, they wanted to know how many people's faces babies saw. If babies only saw a few faces, such as those of family members, they might get very good at recognizing their family's and similar-looking faces, but might be less skilled at recognizing very different-looking faces. Lastly, the researchers wondered how these variables changed as babies learned to crawl and walk, and their visual acuity improved.

Smith's team found that babies saw an average of 8 unique people during the videos--but the number ranged from 2 to 20. The number of different faces babies saw wasn't related to age.  However, the most frequently-viewed faces (generally parents) appeared proportionally less often for older babies. (This was true for the most frequent, two most frequent, and three most frequent faces).

Babies are born with very poor eyesight, which gradually gets more acute. So, not surprisingly, faces were under two feet from the youngest babies, and higher distance correlated with greater age.

Regardless of age, babies typically saw faces from the front, with both eyes visible. Thus, they usually get fairly high-quality views of faces.

There was one surprising finding: The proportion of frames containing faces dropped dramatically with age. The youngest babies saw faces nearly 15 minutes out of every recorded hour, while the oldest saw them only about 5 minutes per hour. So as babies are becoming more competent at social interaction behaviors, they are actually getting less exposure to social stimuli.
Above: The proportion of frames containing faces drops by about half between 1 and 11 months.
From Jayaraman, Fausey & Smith (2015).

A brave new world of objects
So, if older babies are seeing fewer faces, what are they looking at instead? Another head camera study by the same research team [2] suggests an answer.

Smith and colleagues compared head camera views from six 1-3 month old babies, who could neither sit independently nor hold objects, with five 7-9 month olds, who could crawl and manipulate objects.  Forty-four hours of video were sampled every 5 seconds. Younger babies saw mostly faces, ceiling, and walls, with very few objects. By contrast, older babies typically saw hands, objects within close reach, and floors. In order to see objects, younger babies have to have these objects placed within their view by others, or the objects must be coincidentally present near where the babies are lying or being held. But when babies learn to crawl (typically around six months), they spend a great deal of time on the floor and can maneuver themselves within reach of many objects.

Objects, not faces, dominate the visual worlds of babies at the very age they are developing joint attention and social gestures.

Researchers in my department are highly aware of this dynamic, and argue that a central problem for babies in the second half of the first year is to balance the competing demands of attending to others with attending to objects. Because attention control is still limited at this age, this is a big challenge.

This increased focus on objects and decreased focus on faces should not be assumed to reflect a lack of social motivation by these typically developing babies (as would be assumed if they were autistic). Rather, developing motor skills are changing what babies see, and therefore what they can attend to.

How do typically developing babies solve the problem of maintaining social engagement in a world of fascinating objects? They use cues produced by others interacting with objects to share attention. Parents' hand movements are coordinated with their eye gaze, and babies can use these movements to determine what parents are attending to. In so doing, babies consistently look at the same object at the same time as parents, an experience that may allow them to appreciate shared attention before they start using eye gaze or facial expressions as a cue.

Implications for social attention theories of autism
Some researchers speculate that autistic children are biased to look at "nonsocial" stimuli, such as objects or interesting geometrical patterns, more than faces early in life. This in turn limits their exposure to faces and the information they convey, potentially delaying their social development.

Ami Klin's team--well-known proponents of this explanation of autism--even argued that whether male "high-risk siblings" were later diagnosed autistic themselves could be predicted based on how much they looked at the eyes while watching short video clips of a female caregiver.  Although this study was widely reported in the media, Jon Brock points out a number of fatal flaws with this study--including that the trajectories of the later-diagnosed-autistic and low-risk control groups did not actually differ until the final test session at 24 months. When the analyses are carefully restricted to 2-6 month olds only, boys who developed autism showed declining eye gaze while low-risk controls showed increasing eye gaze--but this can be explained simply by the fact that the high risk babies had higher eye gaze than the controls to begin with. 

So, there is plenty of reason to be skeptical about this account of autism even on its own terms.

But it's the research with typically developing babies that truly suggests we should take social attention theories of autism with a large dose of salt. Typically developing babies are reducing their attention to faces and increasing their attention to objects, so if the autism theorists are right, their social development should decline. In fact, it soars. Moreover, rather than distracting babies from social engagement, objects and the hands that manipulate them offer new ways to share attention with others. If attention to objects over faces doesn't necessarily impair social development in neurotypical children, there is no reason to assume that it does in autism, either.

Too often, researchers assume a specific trait, such as social disability in autism, and then reach backwards looking for something to explain it. Or, they might see two traits--social disability and avoidance of eye contact--and link them together, because intuitively, eye contact seems related to social functioning. This is not good science, and the flaws of this approach become especially obvious when it is done without reference to how the trait typically develops, as happened here.

To determine the real explanation, we need to use head camera measures like these, along with eye tracking, to better understand what autistic babies are seeing and doing during this crucial developmental stage. How does this compare with typically developing babies? Are they seeing the same amount and type of faces? Do they see fewer faces and more objects during the second half of the first year, too--or might delays in motor development affect this pattern? Do autistic babies also use others' manipulations of objects to share attention and maintain social engagement? If there are differences here, whatever they are, they are likely to be more subtle and interesting than any social attention theories that have so far been proposed.

[1] Swapnaa Jayaraman, Caitlin M. Fausey, and Linda B. Smith (2015). The faces in infant-perspective scences change over the first year of life. PLoS ONE vol. 10 iss. 5, e0123780. Open access PDF.

[2] Swapnaa Jayaraman, Caitlin M. Fausey, and Linda B. Smith (2013). Visual statistics of infants' ordered experiences. Meeting abstract presented at Vision Science Society 2013.

1 A limitation of head cameras is that the head and eyes are not always perfectly aligned, although they usually are--especially for babies. Another limitation is that they miss peripheral information; however, babies' central vision is much more acute and probably more used anyway.


Does language develop differently in autism? [Summary of book chapter]

Image courtesy of ShutterStock.

When autism first appeared in the "diagnostic bible," the 1980 Diagnostic and Statistical Manual, one of the few criteria for diagnosis was "gross deficits in language development" (APA, 1980).  Autism was once associated with:
"marked abnormalities in the production of speech, including volume, pitch, stress, rate, rhythm, and intonation" (1987)
"marked abnormalities in the form or content of speech, including stereotyped and repetitive use of speech" (1987)
"delay in, or total lack of, the development of spoken language." (1994, 2000).
Today, in the most recent version, language disabilities are not even referenced (2013).

So, as the definition of autism expanded, abnormal language development started out as a defining characteristic, then became an optional trait, and now is no longer part of the diagnosis.

This change might seem strange to most people exposed to autism in the media, and even many who know autistic people personally. After all, many autistic children still do not produce spoken language, and some people who speak fluently sound "odd" in their volume, pitch, or even choice of words. So, what is autistic language like? Has it really changed in the past forty-odd years, or have researchers and clinicians just deemed it less essential?

Morton Ann Gernsbacher, Elizabeth Grace, and I tried to find out. We read hundreds of papers on the topic that came out since 2000. These studies examined every imaginable language skill, in every imaginable age group, with every imaginable method. What we learned might surprise you. Details can be found in our book chapter here, but since it will likely be hard to access, I'm summarizing the important points here.

Autistic Language is Often Delayed.
Studies often find that autistic children develop language more slowly than typically-developing peers, especially when it comes to spoken language. They may be delayed in speaking their first words, first combinations of words (e.g., "blue-car") and first grammatical sentences1-7.

Parents report that young autistic children say fewer words than age peers1,8-14. In fact, their concern about late talking often leads them to seek out a diagnosis15.

Parents also often report autistic children understand fewer words1,8,10,11,16-20. However, parents can easily either underestimate or overestimate what a young autistic child knows. If an autistic child responds with atypical words or body language, or does not respond at all, a parent may mistakenly assume the child does not understand. Alternatively, a parent may think a child understands language associated with a routine (e.g., "let's go outside") when the child really only understands the behavior that accompanies it (e.g., taking the child's coat and shoes out of the closet).

Fortunately, there are more objective ways to measure children's language understanding, which involve testing them directly. These include standardized tests such as the Peabody Picture Vocabulary Test (PPVT) and its equivalent, the British Picture Vocabulary Scale (BPVS); the Preschool Language Scale; or the Clinical Evaluations of Language Fundamentals (CELF). Many studies using such tests indicate delays in understanding language, not just speaking8,9,10,17,20-29.

Autistic Language is Variable.
Some studies do not find any difference between autistic people and age peers30-34. These studies range from toddlers to adults, and evaluate skills as various as spoken vocabulary, understood vocabulary, and quality and quantity of writing.

Typically, studies find a wide range of performance in autistic groups. The majority are often unimpaired, while a minority may have significant delays35,36. Some examples:

  • One group surveyed parents of a large sample of autistic toddlers with a wide range of IQ scores. Over three quarters of this group said their first words before 18 months, which is within the range of typical development. However, a little over 5%  had still not spoken their first words by six years of age--a huge delay.37
  • In a group of autistic children and teenagers, half had average receptive vocabulary scores (on the BPVS). One quarter performed one to two standard deviations below average, and another quarter scored over two standard deviations above average.38

Standard scores often range from as low as 4 standard deviations below average to two standard deviations above28,39-41. Thus, autistic people can rank among the most language impaired--or the most verbally gifted.

When researchers measure the rate of language development--instead of ability level at a given moment in time--autistic people are similarly variable.

Sometimes, despite lower initial performance, autistic people develop language skills faster, and for longer, than age peers6,42. Vocabulary may even improve into adulthood43.

However, different individuals have very different rates of language development. The graph below shows the growth in spoken vocabulary development for 35 autistic preschoolers44. Parents reported these children's vocabulary (using the MacArthur-Bates Communicative Development Inventory) four times over two years.

All the children started with a spoken vocabulary of fewer than 60 words, but they ended up with very different vocabulary sizes two years later. Those with the steepest growth could say nearly 700 words at the end of the study; another group showed little change at all. All these children were the same age, with similar levels of autistic traits, and similar measured IQ. Interestingly, they were also all undergoing the same interventions--which included speech and language therapy.

Overall, it seems that language development can be slower than normal during the first few years of life45, but more rapid later on. However, individuals differ so greatly that it would be hard to identify a "typical rate" of autistic language development.

Autistic Language is Similar to that of People with Similar Language Skills.
Psychologists often draw a distinction between "delay" and "deviance." Delay is when a person develops in the same way as others, but does so more slowly. For example, someone with delayed spoken vocabulary might have the vocabulary of the typical two year old at the age of six. Deviance is when a person develops in a qualitatively different way. They might develop a different pattern of skills, or they might develop the same skills in a different order. For example, some people have claimed that autistic people have a unique difficulty understanding nonliteral language, such as metaphors. A person with a disability could, in theory, be delayed, deviant, or both. So, do autistic people have "deviant" language, or are they just more likely to be delayed?

In order to answer this question, we have to compare autistic people to those with similar levels of language development, but who are not autistic. Such comparison groups might include younger typically-developing children, late talkers, or children with specific language impairment. If autistic people are simply delayed, they will learn the same language skills in the same order as these "language-matched" peers.

And in fact, they do.

Autistic children do not have a unique difficulty with learning social or emotional words, or an advantage in learning words associated with special interests. They learn the same words in the same proportion and in the same order as younger typically developing children. For example, they are no less likely to learn words for people or social routines, and no more likely to learn words for vehicles.1 They also are no less likely to say emotion words46.

Autistic people also do not have any reliable difficulty with understanding and using nonliteral language, once their general language delays are taken into account. Autistic children in grade school learn to understand metaphors, draw inferences from stories, and structure their own narratives at the same time as language-matched peers47-52. Their level of language impairment, not their degree of autistic traits, predicts how much difficulty they have with nonliteral language47-51.

Autistic children sometimes develop language for a time, then seem to abruptly lose it--this is called "regression." Some people have argued that regression is characteristic of, and unique to, autism.

Regression is hard to define and measure. However, it seems that only a subgroup of autistic children lose language this way. Interestingly, those who lose language were previously experiencing little or no delay53,54.  Language loss also occurs in a seizure disorder called Landau-Kleffner syndrome.

Some people have claimed that autistic children use language in unique ways--for example, echolalia (repeating what they or others say), or pronoun reversal (e.g., switching "you" for "me" and vice versa). These characteristics appear to occur in only a small minority of autistic children, and are reported less and less frequently now that they are no longer included in the diagnostic manual. They also occur in other disabled groups.

Pronoun reversals do not occur in all autistic children, and they also occur in other populations (see my earlier post here, and Dr. Jon Brock's here). Young typically developing children sometimes confuse first- and second-person pronouns for a short time while learning them55. Children with other developmental disabilities, such as Down Syndrome, also reverse pronouns56.  Like these other groups, autistic children are more likely to have difficulty producing the correct pronouns when using more complex sentences, or complex types of pronouns57-60. Thus, pronoun reversals may be a normal part of early language development; it simply lasts longer in autistic children and those with Down Syndrome because their language develops more slowly.

Echolalia was once viewed as unique to autism. However, very young typically developing children also produced echolalia--that is, they imitate all or part of the preceding utterance without any change. As they get older, they produce less echolalia61,62. Similarly, autistic children also may produce less echolalia as their language improves. The majority of children who were reported to have "lost" their autism diagnosis by age nine had once exhibited echolalia, but no longer did so63. A longitudinal study followed autistic and non-autistic children with language delay and measured their increase in language comprehension. During this time period, both groups made fewer immediate, exact repetitions, and increased their use of mitigated echolalia (e.g., making small changes to the repeated sentence to better express the desired meaning)64. Echolalia appears to be a stepping stone to full self-generated language, and it may last longer in autistic children when their language develops more slowly.

Some people, after observing young autistic children progress from repeating whole phrases unchanged to self-generated speech, have concluded that autistic children must learn language in an entirely different way than typically developing ones. That is, whereas typically developing children first learn what words mean and then how to put them together, autistic children first learn whole phrases, and only later learn what the words mean and what grammatical rules link them together. As far as I know, this hypothesis has yet to be directly tested with a large group of young autistic children. However, there is also nothing more than anecdotal evidence for it. If every known population learns language in one way, the burden of proof must be very high to show that one group learns it in the opposite way.

What can we conclude about language in autism?
In short:

  • Autistic people's language is heterogeneous. Their language ability at any given time ranges from the most delayed to the most advanced possible. Their rate of development ranges from virtually nil44 to nearly ten times that of typically developing peers42
  • Language delays are common in autism.
  • Autistic language is "delayed, not deviant." Researchers have yet to identify any characteristics of autistic language that are universal in autism or cannot be found in other groups. Autistic language is not unique, but continuous with typical development and language disabilities.

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Disability, difference, and impairment: What's the difference?

If you've spent much time in the autism community, you've probably seen people arguing about whether autism is a difference, a disability caused by autism itself (an "impairment"), a disability caused by society, or a disability caused by both. So, what do these terms mean, and why does it matter? 

To make these issues clearer, let's look at some examples that have nothing to do with autism.

At one time, left-handedness was considered bad. Children were punished for writing using their left hands, and forced to write with their right. This occurred until quite recently, and still seems to occur occasionally in the U.K. President Obama reports that, as a child in Indonesia, his teachers hit him with a ruler for writing with his left hand. President Obama explains that left-handedness was viewed as impolite in Indonesia, and a variety of other negative associations exist. In cultures that developed a practice of eating, interacting and handling food with the right hand while cleaning their bodies with the left, the left hand was considered "unclean" and regarded with disgust. In Christianity, Jesus sits at God's right hand, while those who have lost God's favor are described as "sent to the left."

A disability is when people's characteristics do not fit with the society in which they live, which leads to bad treatment, diminished opportunities, and ultimately, less success in life. See, for example, the Americans with Disabilities Act's definition of "disability," whose last sentence hints at the important role of society:
An individual with a disability is defined by the ADA as a person who has a physical or mental impairment that substantially limits one or more major life activities, a person who has a history or record of such an impairment, or a person who is perceived by others as having such an impairment. 
Left-handedness was then a disability, for several reasons. First, left-handed people were viewed and treated negatively. Second, the environment was not accessible to them: everyday tools and furniture (e.g., desks) were set up for right-handers, making them difficult for left-handed people to use. Lastly, the educational system was dedicated to eliminating left-handedness. 

Today, many of us see this discrimination against left-handed people as backward. We realize there is nothing inherently wrong or harmful about using the left hand. If society had not chose to view left-handedness as bad, it would not be a disability. Left-handedness is not an impairment, something that would make it hard for people to do important activities no matter how they are treated. It is simply a harmless difference. Choosing to view a trait like left-handedness as an impairment makes it into a disability. 

However, if we could talk to the teachers who punished children for using their left hand, we would probably find that they believed left-handedness was an impairment. They probably thought they were doing the child a favor. If they could just make the child more like the right-handed majority, he would never face stigma or lose access to jobs and relationships. In other words, they probably were like many teachers and clinicians working with disabled children today. They saw that left-handedness was a disability, and instead of blaming the true cause--society--and trying to change it, they blamed the trait and set out to eliminate it. The only difference between those teachers then and special educators today is whether their culture considered left-handedness an impairment or a difference. 

That should make us alert to the possibility that some of the disabilities we currently consider impairments are just differences, like left-handedness.  Our children will probably look back at our treatment of stuttering, learning disabilities, autism, or ADHD with the same disgust and pity we have when considering how our ancestors treated left-handed people.

That, in fact, is the great insight of the neurodiversity movement--that people come with a wide variety of traits, and that this diversity makes the human species healthier and more likely to survive. While it's natural for humans to devalue minorities, like left-handed people, the world would be worse off without them in it. Because we are prone to view all differences as impairments whether or not they really are, we should be cautious about attempts to eliminate their disabilities--especially if it involves treating them in ways we would never treat a non-disabled person. Furthermore, the more subjective the impairment (e.g., "inappropriate" social interaction), the more skeptical we should be.

Some things we currently consider impairments may really be impairments. Even so, stigmatizing people and limiting their access to the world only makes their impairments worse. A person who cannot walk can still move around at will and live independently if there are wheelchairs, sidewalks and curb cuts, but could not before the Americans with Disabilities Act (ADA) made these technologies widespread. 

It would be hard to imagine any impairment that could cause as much suffering as being excluded from school, fired from jobs (if you are even hired at all), unable to access transportation, denied the right to vote, forcibly sterilized, forbidden to enter into contracts, or denied medical treatment. This was the normal state of affairs for people with disabilities before the ADA, and some of this treatment continues today.

One reason many people with disabilities like the term "disability" is because it acknowledges the importance of society in making people disabled, while embracing the whole spectrum from those who are a little different to those who are severely impaired. This invites people with a variety of disabilities--and attitudes about their own disability--to work together. (I have seen fewer parents of disabled children who are comfortable with the term "disability"). 

In short: A difference is a harmless trait, like left-handedness. An impairment is a trait that makes important activities difficult or impossible. A disability can be either a difference or an impairment. The distinction matters. However, for both, the way society treats people with disabilities may be what holds them back most.


Is all research really "me-search?" And is "me-search" bad?

J. Sumerau at “Write Where it Hurts” makes a provocative argument that the word “me-search” is used as a slur, and that all scientific research is, in a sense, “me-search”:
"In my experience, many scholars refer to work that engages some aspect of personhood as me-search. While this is a cute phrase, it is generally used to bolster claims to objectivity and/or to marginalize scholars who work in areas that have personal significance for them. ...On the surface, the best answers I have been able to find for this question at conferences, online, in departments, and in informal conversations suggests the therm refers to any case where someone conducts research in an area or with a population that is personally relevant to them. Based on this suggestion, me-search could actually just be considered a synonym for science. When, for example, an American demographer studies American population trends, ze is conducting me-search because ze is studying zir own population...One could even go so far as to say that if science is the study of the natural world, all science is me-search because all of us are parts of the natural world, and both influence and are influenced by this phenomena. Unless someone can find some area of study that does not influence human life or somehow become non-human prior to doing any kind of research, all research is ultimately me-search because all research seeks to make sense of the world we (or me) live in to the best of our current abilities."
Sumerau seems to be right about how the term “me-search” is used. A heterosexual psychologist who studies heterosexual couples would not be accused of doing “me-search,” while a gay man studying homosexual couples would be. Heterosexual psychologists studying mainly heterosexual couples are quite common in relationship research, and they often appear to present themselves as researching the relationship of couples in general, regardless of sexual orientation. They can get away with this because the vast majority of people are heterosexual or in opposite-sex relationships, so even if many individuals are completely different from these research participants, the average person is like them. Because homosexual couples are in the minority, a researcher studying them could not claim to be studying couples in general, even if she wanted to.

Thus, I agree that “me-search” is in the eye of the beholder. “Me-search” is a way of denigrating the subjectivity of those in the minority while ignoring that of those in the majority. However, subjectivity comes with problems that Sumerau does not even mention. The problem is not that people ask minority researchers engaged in “me-search” to question their assumptions and biases. The problem is that they are not asking majority researchers to do the same.

("Me-search” is a continuum, not a binary. Sumerau’s first example—American demographers studying American population trends—is uncontroversially “me-search,” while his last example, a physics or geology study, seems much less so. In a trivial sense, yes, studying the natural world is “me-search” because we live in the world and understanding it better will change our technology, our behavior, and the way we understand the world. But, are our identities bound up in whether the Higgs boson exists? Frankly, most of us don’t care if there is a Higgs Boson, both because the phenomenon itself is distant from our experience, and because we don’t think discovering it will have much effect on our lives. By contrast, determining whether people have free will could alter how we see ourselves and perhaps administer justice. Discovering what makes people happy would not only affect our lives, but also directly concerns our experience. Physics seems “objective” and not like “me-search” and sociology the opposite because physics is more remote from our experiences, concerns, and identities than sociology. So, I disagree with Sumerau’s claim that everything is me-search, and therefore nothing is me-search. Different research areas can involve more or less me-search, and the difference matters).

I believe “me-search” should be undertaken with a great deal of critical thinking and self-examination. When our identities are at stake, we tend to engage in two behaviors that hamper our reasoning and communication: motivated reasoning and non-constructive arguments. Guarding against these requires constant vigilance. When our identities become part of our work, the opportunities for motivated reasoning and non-constructive arguments multiply.

The first pitfall of Me-search: Motivated Reasoning
No one is immune to motivated reasoning: the tendency, when our values and identities are at stake, to cling to evidence that supports our beliefs while ignoring or rejecting counterevidence. We look for ways to discredit those with whom we disagree, while ignoring the misdeeds of our own side. If you regularly read scientific papers, for example, you might find yourself poring over tiny details of the methods and statistics in papers you disagree with, while skimming papers you want to cite to support a point you were already planning to make in your introduction. When no legitimate evidence comes to hand, people even build elaborate conspiracy theories, and if all else fails, attack their opponents' motivations. For example, in the absence of evidence that vaccines cause autism, people with this belief allege a government coverup of the evidence, or claim their opponents are funded by drug companies. Attacking their opponents' funding works because drug companies are associated with corruption and untrustworthiness, which provides a convenient excuse to ignore the researchers' message. Of course, funding isn't a magic button you press to get exactly the result you want. Just because someone is funded by a corrupt source does not mean that their results are wrong, or were obtained with unethical methods. This argument is only convincing if you are already looking for an excuse to disbelieve).

Ironically, descriptions of motivated reasoning, like this one from Skepdic.com, are often good examples of motivated reasoning themselves. They use examples that are far outside the mainstream of public opinion (or at least, educated public opinion), such as “the Apollo moon landing was a hoax,” “the Holocaust did not happen,” or “evolution is a hoax.” This makes it seem as if only conspiracy theorists and the extremely religious engaged in motivated reasoning, while educated, skeptical people—like the audience of Skepdic.com—would never fall prey to such an error. This is an example of all the key ingredients of motivated reasoning—a self-serving belief, hypersensitivity to opponents’ errors, and blindness to one’s own. No one is more susceptible to motivated reasoning than those who believe themselves immune to it. 

The second pitfall of Me-search: Destructive emotional reactions
When identities are at stake, heated disagreements can go from productive debates to feuds, or cutting off communication entirely. The intense arguments that blow up occasionally on the Thinking Person’s Guide to Autism’s website and facebook page are a great example.  A certain sort of non-disabled parent of autistic children has invested an identity in being an “autism mom,” a “warrior”   “fighting autism” in order to “get their kid back.” It follows directly from the messages about autism promulgated by the media and the largest autism charity, Autism Speaks. And to a parent who feels overwhelmed by parenting a child with a disability, resents it, and doesn’t feel supported, this narrative gives them control and purpose, making them feel more heroic and less helpless. The problem, of course, is this ideology comes from attacking a basic part of their child that cannot be removed, and easily leads to ignoring the child’s communication, treating them with utter disrespect, making them feel hated, traumatizing them for years, abusing them, putting them in abusive therapy, or even murdering them. When parents talk about parenting their child this way, it presses all thebuttons of autistic people who have been traumatized by parents who behaved that way. Often, autistic adults lash out. But even if they find the commendable patience to politely explain why these parents are being hurtful, the parents react even more viciously. While parents’ rhetoric is an existential threat to autistic adults’ identities, autistic adults’ claim that parents might be hurting their child hits them in the part of their identity that matters most—their role as a parent. Most react defensively, although a few have listened and have transformed the way they view their role and parent their child—a change that improved their mental health. In short, both autistic adults and nondisabled parents feel their identity is threatened and react defensively, leading to over-the-top arguments, people being banned from the community, and many of the debaters cutting off communication by blocking each other on Twitter and Facebook. Emotional reactions based on identity can prevent people from communicating and working together.

Less extreme versions of these blowups occur in research, not just in the autism community. Psychology is full of theoretical disagreements that sometimes border on personal feuds, such as the old one between Lance Rips and PhilipJohnson-Laird, or the more recent one between Isabel Gauthier and Nancy Kanwisher . Since I am closely connected with people on one side of each of these debates I will not discuss any details. Each involves a long series of papers, so I invite you to read them and see for yourself. Personally, I think that the papers would have been clearer and more inviting to read had they been written in a less emotional context.

The Benefits of Me-search
So, if bringing identity into research can lead to motivated reasoning and personal feuds, does that mean everyone should avoid doing “me-search?” I think not, for two reasons.

First, lived experience provides knowledge that might be difficult or impossible for outsiders to gain. Autistic people talked about sensory overload and other sensory processing problems for decades before neurotypical researchers took an interest. Many autistic people and parents noticed echolalia can be a first step towards generating one’s own communicative language; only a handful of neurotypical researchers, such as Barry Prizant  in the 1980’s bothered testing the hypothesis. Many proclaimed the opposite and a few recent papers still do. In fact, behavior programs have tried to discourage echolalia (e.g., this). Yet, although responsive communication from caregivers helps typically developingchildren develop language, (and also autistic children), we don’t even know if having their best language ignored or discouraged by therapists stunted generations of autistic children’s development. Autistic people have known for a long time that stimming has many positive functions; researchers are still looking for new ways to stop them from doing it through behavior modification or even drugs.

Autism viewed from the outside is different from autism experienced from the inside, and both are aspects of what autism, the phenomenon, actually is—a set of genetic, brain, mind, and behavior states. If only neurotypical clinicians research autism, then we will not have the complete picture—we will only learn about autism as viewed from the outside. While autism-viewed-from-the-outside is real and sometimes important, it is not necessarily the most important part of autism. Without understanding autism-from-the-inside, we risk confusing the outward appearance of autism with what it really is. We would not have been stuck with obviously inadequate psychoanalytic, theory of mind, or “extreme male brain”  explanations of autism for so long had autistic people been involved sooner in researching their own condition.

Me-search is also important in so-called “translational” or “clinical” research fields, where the goal is to learn something that will improve people’s lives. People in a particular group do not always focus on the same outcomes as those outside of it. For example, autistic people often want to see less emphasis on finding causes and cures, and more emphasis on services, education, and employment. By contrast, people with ME or chronic fatigue syndrome would like to see more basic biochemical research on the causes behind their symptoms.  In both cases, those with the condition disagree with those doing the research—who do not have it. When people in a specific group have a say in what outcomes are considered helpful, research is more likely to actually help them. 

Me-Search: Approach, with Caution
I support neurodivergent people researching their own and similar diagnoses, so long as they observe themselves carefully to avoid motivated reasoning and unhelpful emotional reactions. I would also like to see neurotypical psychologists and neuroscientists recognize that they are engaged in “me-search,” and take similar precautions.

We need to be careful about endorsing theories that fit our experiences regardless of the strength of the evidence. For example, many autistic and other neurodivergent people describe being sensitive and overreactive to other people’s emotions. Thus, even before learning the details, I am predisposed to support the intense world theory of autism, proposed by Kamila and Henry Markram. Intense World Theory proposes specific neural mechanisms behind this hypersensitivity, based on rodent research. They also propose a specific way of raising autistic children that contradicts findings in typically development research: Because autistic people are hyperaroused all the time, the Markrams recommend providing very little stimulation, whereas in typically developing humans and animals, deprivation of stimulation can actually cause developmental delays. While I and others may be tempted to adopt Intense World Theory because it fits experience well, it need not be the correct mechanism. Not every promising finding in rats translates to humans. Even if this mechanism is correct, that may not imply that drastically reducing sensory input is good for autistic development. For example, maybe gradual increases in exposure would help them learn to tolerate the environment better. Or maybe the optimal level of stimulation is lower than typical, but not as low as the Markrams suggest. The Markrams’ research program will have to follow two steps: demonstrating that intense world theory applies to a significant portion of autistic humans, and determining whether reduced stimulation really does help. These are separate programs requiring very different research skills, and each will likely take years.

We also need to be careful to avoid dismissing any research evidence that contradicts our experiences. When our identities are involved, we may be more tempted to explain away contradictory evidence, for example, by calling it a methodological problem. (Maybe they didn’t design their task right, or choose the right participants, or explain their task properly). This is easy to do because there are lots of small factors that go unreported that affect how a study comes out, and sometimes there really are methods problems. But we have to be willing to admit when our theories are wrong—even when they’re based on personal experience—or we’re not doing science.

Many researchers probably have difficulty acknowledging their mistakes, and not all of them do me-search. Me-search simply increases the temptation. Me-searchers might have an easier time letting go of theories based on experience if they remind ourselves that they may not be representative. What they know about themselves may not be true of the whole population they study.

Sumerau seems insufficiently concerned with these pitfalls of “me-search.” However, he or she lays bare the unequal way “me-search” is used, to discredit those in the minority and reassure those in the majority. Neurodivergent researchers who want to research similar groups need both sorts of knowledge. They need to know the sociology of terms like “me-search” so they can combat this prejudice. They also need to understand the biases that come with me-search so their identities help, not harm, their science. Armed with this knowledge, they could transform their fields.

For their part, neurotypical psychology and neuroscience researchers who study the general population need to recognize that they are doing "me-search," and are just as susceptible to biases as those in the minority. If anything, they may be more so. Because those in the majority encounter more people like themselves, they can more easily have their "people are like me" biases confirmed. If researchers recognized identity-based biases as a normal part of researching human beings, not some weird property of minority researchers, they would do better science. 


How can you measure a non-speaking person's understanding of language?

The autism community has become increasingly concerned about understanding people with no spoken language, and often, severe developmental delays. Such people have previously been excluded from many research studies, in favor of more convenient subjects. However, psychology offers a variety of tools for learning about the mental life of people who cannot speak, most of which involve measuring eye movements. Some of these, such as habituation/preferential looking, come from research with babies. This makes sense, because working with babies means making inferences about the thoughts of people with little or no speech or gesture. Surprisingly, another paradigm comes from research on how adults interpret language, and is called the "looking while listening" or "visual world" paradigm.

Visual World Paradigm
Image result for visual world paradigm
Example of the visual world paradigm, using the words "peach," "beach," "sheep," and "lock."
Back in 1974, a researcher named Cooper measured people's eye movements while they listened to short narratives and looked at pictures of common objects. Some of the objects were referred to in the spoken narrative, while others were not. Participants were told their pupil size was recorded, but they could look anywhere they wanted. The listeners tended to look at objects that were being mentioned in the narrative--either while the word was still being spoken, or within about 200 ms after it [4]. In the 1990's, when eye movements became easier to measure, Tanenhaus's research team found something similar. The method, dubbed the "visual world paradigm," quickly took off [4].

While people do not consciously choose to look at the objects they are thinking about, and may not even realize they're looking at them, their eye movements still reflect their thoughts.  That makes the visual world paradigm attractive for understanding language comprehension.

Researchers used this method because they were interested in how people's language abilities interacted with their non-language ones (such as the ability to recognize objects)[4]. They were also interested in when and how we distinguish a word from other, similar-sounding words. While it feels like one recognizes short words all at once, they actually take several hundred milliseconds to say. During this time, information about the word gradually accumulates, and your brain uses it to predict what word the person is saying. The visual world paradigm can be used to measure how long it takes to distinguish a word (e.g., "beaker") from another word that sounds the same at first (e.g., "beetle"), as opposed to a rhyming word (e.g., "speaker") or a completely unrelated one ("dolphin") [1]. The first study I ever worked on [2] used the visual world approach with these exact types of words, while measuring brain activity with EEG.

An important aspect of this method is timing. It doesn't just matter which picture people look at, it matters when they look at it. The timing for the eye movement data is matched up very precisely with the timing of the audio and the picture, or "time locked." Then one can say, for example, that at the point where the speaker has said "bea," the listener glances at both the beetle and the beaker, but by the time the word finishes, the listener is only looking at the beaker.

Looking While Listening
A simpler version of the visual world paradigm, the "looking while listening" procedure, is used to measure very young children's language comprehension [3]. Children look at a pair of pictures while listening to speech that names one of the pictures. Just as with visual world, their gaze patterns are measured and time-locked to the speech signal.

One difference is that only two pictures appear onscreen instead of four. Fewer distracters is suitable for very young children, or those with limited ability to control their attention. The pictures are also very carefully matched on how bright and interesting they are.

Researchers code where the child is looking during each trial a frame at a time. Trials are categorized depending on where children are looking when the word begins and ends [3].

For example, if a child starts out looking at the correct object (the "target") and continues looking at it the entire time the word is presented, this is a "target-initial" trial. This pattern reflects comprehension. If the child starts out looking at the distracter picture, but shifts during the word to looking at the correct picture, this is a "distracter-initial trial," and it also indicates comprehension.

Certain patterns indicate the child probably does not comprehend the spoken language presented, including:
  • The child starts out looking at the distracter picture and never shifts to looking at the correct picture.
  • The child starts out looking at the target picture and switches to the distracter.

Other patterns suggest that the child was not performing the task at all, and his or her comprehension can't be judged:
  • The child was looking somewhere between the pictures the whole time and not directly at either of them.
  • The child was looking away (not at the display at all) the whole time.
Data can be plotted continuously, like this, to see how children's comprehension gradually unfolds, and how it improves with age:
Above image is from Fernald and colleagues (2008) [3].

However, other measures are more intuitive and easier to compare between groups. Perhaps the most intuitive is accuracy, the proportion of time spent looking at the correct picture as opposed to the distracter (or anything else) [3]. If the child consistently looks at the labeled picture for most of the time, then he or she probably understands that the label refers to that picture.

Children look more consistently at the correct picture as they get older and develop higher language skill. Looking while listening comprehension might also reflect individual differences in language abilities in general. For example, typically-developing children with higher looking while listening comprehension at 25 months may have higher standardized language scores (CELF-4) at 8 years [3].

Using looking while listening with autistic children
Looking while listening has been used to measure young autistic children's language in their own homes [5]. Children view videos with two side-by-side images, accompanied by audio that only matches one of the images. If children understand which image matches the audio, they will look at it rather than the distracter. Videos were used instead of static pictures because these are better for measuring children's understanding of verbs, including who did what to whom. This video by Letitia Naigles and Andrea Tovar [5] show how the videos are designed and presented to children. It's a great example of how high-quality, well-controlled research can be done outside the lab, so participants can be comfortable.

Of course, this method isn't perfect. One question to be resolved is how well it works for people with difficulty making eye movements. Difficulty making controlled eye movements sometimes occurs in autism, and may be especially common in those with language impairments. The eye movements made during the looking while listening paradigm are not deliberate, so I am not sure if a person with difficulty making controlled eye movements would also have difficulty with these. If so, this task won't be suitable for every nonspeaking person. But no assessment method is suitable for everyone, and this is more accessible than most standardized tests.

Measuring people's understanding of nouns, verbs, and sentences is very far from understanding a person's experience. So, the looking while listening paradigm and similar methods do not completely solve the problem of understanding nonspeaking people. However, they might help with presuming competence and offering an appropriate education. When we can actually measure whether a nonspeaking person can understand what we say to them, we no longer have any excuse for assuming they do not understand. Most likely, many nonspeaking autistic people will demonstrate comprehension beyond what their parents or teachers predicted.


  1. Paul D. Allopenna, James S. Magnuson, and Michael K. Tanenhaus (1998). Tracking the time course of spoken word recognition using eye movements: Evidence for continuous mapping models. Journal of Memory and Language vol. 38, pp. 419-39.
  2. Amy S. Desroches, Randy Lynn Newman, and Marc F. Joanisse (2009). Investigating the time course of spoken word recognition: Electrophysiological evidence for the influences of phonological similarity. Journal of Cognitive Neuroscience vol. 21, iss. 10, pp. 1893-1906. Full text HTML.
  3. *Anne Fernald, Renate Zangl, Ana Luz Portillo, and Virginia A. Marchman (2008). Looking while listening: Using eye movements to monitor spoken language comprehension by infants and young children. In: Irina A. Sekerina, Eva M. Fernandez, & Harald Clahsen (editors), Developmental Psycholinguistics: On-line methods in children's language processing xviii, pp. 97-135. Open access PDF.
  4. *Falk Huettig, Joost Rommers, and Antje S. Meyer (2011). Using the visual world paradigm to study language processing: A review and critical evaluation. Acta Psychologica vol. 137, pp. 151-71.
  5. *Letitia R. Naigles & Andrea T. Tovar (2012). Portable intermodal preferential looking (IPL): Investigating language comprehension in typically developing toddlers and young children with autism. Journal of Visual Experimentation 70, e4331 (Paper & video). URL.