Autism is a mysterious developmental disease because it often leaves complex abilities intact while impairing seemingly elementary ones. For example, it is well documented that autistic children often have difficulty correctly using pronouns, sometimes referring to themselves as "you" instead of "I."
A new brain imaging study published by scientists at Carnegie Mellon University (CMU) provides an explanation as to why autistic individuals' use of the wrong pronoun is more than simply a word choice problem. Marcel Just, Akiki Mizuno and their collaborators at CMU's Center for Cognitive Brain Imaging (CCBI) found that errors in choosing a self-referring pronoun reflect a disordered neural representation of the self, a function processed by at least two brain areas — one frontal and one posterior.
"The psychology of self — the thought of one's own identity — is especially important in social interaction, a facet of behavior that is usually disrupted in autism," said Just, a leading cognitive neuroscientist and the D.O. Hebb Professor of Psychology at CMU who directs the CCBI. "Most children don't need to receive any instruction in which pronoun to use. It just comes naturally, unless a child has autism."
For the study, the research team used functional magnetic resonance imaging to compare the brain activation pattern and the synchronisation of activation across brain areas in young adults with high-functioning autism with control participants during a language task that required rapid pronoun comprehension.
The results revealed a significantly diminished synchronisation in autism between a frontal area (the right anterior insula) and a posterior area (precuneus) during pronoun use in the autism group. The participants with autism also were slower and less accurate in their behavioral processing of the pronouns. In particular, the synchronisation was lower in autistic participants' brains between the right anterior insula and precuneus when answering a question that contained the pronoun "you," querying something about the participant's view.
"Shifting from one pronoun to another, depending on who the speaker is, constitutes a challenge not just for children with autism but also for adults with high-functioning autism, particularly when referring to one's self," Just said. "The functional collaboration of two brain areas may play a critical role for perspective shifting by supporting an attention shift between oneself and others.
"Pronoun reversals also characterise an atypical understanding of the social world in autism. The ability to flexibly shift viewpoints is vital to social communication, so the autistic impairment affects not just language but social communication," Just added.
REHACARE.de; Source: Carnegie Mellon University
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