William’s Syndrome and Autism: Two Extremes on the Social Spectrum

August 23rd, 2010 in Uncategorized 0 comments

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Are you an extravert or an introvert? It is likely that if you have not been asked this directly, you have been tempted into the bi-categorical systemization in the privacy of your internal self-judgment. These two prototypes which show some truth in the extremes of human sociability are represented in the symptoms of William’s Syndrome and Autism. Recent studies focusing on the contrasting linguistic abilities associated with either disorder illumined a correlation between linguistic aptitude and sociability (consequently also drawing a correlation between linguistic ineptitude and unsociability).

The symptoms of the two disorders oppose one another all the way down the line. Meet Peter. Peter harbors no hostilities towards others. In fact, he feels quite indifferent around others, perhaps, moderately uncomfortable. He has little to say, unless the topic falls on one of his oddly specific hobbies. The conversation then bounces from one piece of chit chat, gossip, and light anecdote to another with erratic playfulness. Peter doesn’t disapprove of anything said; he simply finds no need to comment. He observes it with a disinterested blankness, so that the look on his face could not tell one way or another as to his affect or comprehension.

He sees a Rubik’s cube on a shelf nearby, which is of far more fascination to him. He observes people blankly, but objects illumine his eyes like one experiencing spiritual reverie. He finishes the puzzle in less than a minute. He perks up only when the conversation touches upon the esoteric topic of the impossible last problem on the physics exam, which he explains with enthusiasm on the spot, mostly looking at the room, rather than people’s faces. He mumbles as if  there were no audience. Peter exemplifies the Autistic persona. Characteristics vary on a spectrum, but key qualities are depreciated response to social cues, greater fascination with objects than people, standoffishness, high spatial or mathematical ability, and a tendency toward the literal, rather than the conceptual.

Introversion

Now meet William. When presented with Peter’s Rubik cube he strains with it for a few moments before abandoning it completely to study Peter’s face. He watches with delight as Peter’s eyes move to the floor to avoid his gaze, but William stares with unbreakable solidity at Peter’s eyes. William could hardly begin to solve the physics problem Peter was just explaining, but he narrates the events of the test day with incredible fluidity. He rejoices at his ready audience and speaks unrestrainedly as one would only to a friend, though they are all total strangers.

William exemplifies the syndrome he is named after in his lack of social reservation, high responsiveness to facial emotionality, linguistic capability, and low spatial intelligence going hand in hand with his poor IQ test performance. Approximately one in 10,000 people have this disorder, which is the result of a genetic deletion leading to an altered amygdala structure (an area of the brain highly involved in social and emotional processes). Those with William’s syndrome demonstrate higher than normal reactions on brain scans to happy facial expressions and lower than normal ones to unhappy ones, suggesting a cause for their extreme extroversion. Those with autism express a lower than normal reaction to positive facial expression. However, William’s syndrome is attributable to a particular genetic deletion, while autism exhibits more variance.

The extreme contrast between these two disorders led to an investigation in the differing mechanisms of language processing in the brains of individuals with either disorder to find a correlation between linguistic aptness and sociability. Inna Fishman and Debra Mills focused on the so named N400 pattern of electrical brain activity, measured through electrodes on the scalp. The N400 is part of a normal brain response to words and meaningful stimuli that peaks 400 milliseconds after the stimulus. Participants were given odd sentences such as “I take my coffee with sugar and shoes.” Those with WS had an abnormally high response in comparison to the control, while those with autism did not show such negativity, demonstrating an inability to integrate lexical information into an overall conceptual context. This demonstrates that those with autism have difficulty with non-literal or conceptual meaning.

Comparing with preliminary data, there was a direct correlation between level of sociability and N400 response. The study revealed a connection between the degree of social aptitude and linguistic ability. It seems likely that depreciated language ability would be related to social ineptitude. However, the complexity of what makes one socially apt and what makes one withdrawn reaches a greater level of depth than the exposed correlation. Nonetheless, the juxtaposition of these two social extremes is a fascination in itself, and study often wins merit not by grasping truth in its entirety, but by probing it.

Language as a Window into Sociability
Science Daily Article
Sociability Traced to Particular Region of Brain Science Daily on William’s Syndrome

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