The broad autism phenotype

Published on February 27, 2020   32 min

A selection of talks on Neurology

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Hello, my name is Noah Sasson. I'm an Associate Professor of Psychology at the University of Texas at Dallas. My research examines mechanisms of social disability in autism. Today I'm going to be talking about "The Broad Autism Phenotype", which is generally defined as mild characteristics of autism that don't meet the threshold for diagnosis.
So the concept of the broad autism phenotype dates back to the earliest clinical descriptions of autism, including Leo Kanner's seminal 1943 paper in which he presents 11 highly detailed case studies of children who he described as having a "disturbance of affective contact". So what he wrote in this paper is that "these children have come into the world with an innate inability to form the usual biologically provided affective contact with people, just as other children come into the world with innate physical or intellectual handicaps". So he conceptualizes autism as primarily a social disorder, but he also notes some non-social features as well, such as repetitive behaviors, fixated interests, and an insistence on sameness. All of these characteristics, of course, are reflected in the current diagnostic criteria in the DSM-5.
Kanner's first case study was a boy named Donald. Kanner first observed Donald in 1938 when Donald was five years of age. But what's very interesting about this case study is that Kanner wasn't the first one to provide a detailed description of Donald. Rather it was Donald's father who first wrote Kanner about his son and described his behavior and tendencies with great acuity and specificity. For instance, he wrote that, "At one year, Donald could hum and sing many tunes accurately. He very soon new an inordinate number of pictures in a set of Compton's Encyclopedias. He quickly learned the whole alphabet backwards and as well as forwards and to count to 100, but he was not learning to ask questions or answer questions. He seemed to be self-satisfied. He had no apparent affection when petted, he does not notice when anyone comes or goes, he seems to draw into his shell and live within himself. When interfered with, he has temper tantrums during which he is destructive. At two years, he developed a mania for spinning blocks and pans and other round objects." So Kanner noted that this 33-page letter sent by the father was full of "obsessive detail" and described the father as successful, meticulous, hardworking, who takes everything very seriously. "When he walks down the street, he's so absorbed in thinking that he sees nothing and nobody and cannot remember anything about the walk." He also said, "There's a great deal of obsessiveness in the family background."