Neurocognitive and electrophysiological evidence of altered face processing in parents of children with autism: Implications for a model of abnormal development of social brain circuitry in autism Dawson G, Webb SJ, Wijsman E, Schellenberg G, Estes A, Munson J, Faja S Abstract: Dev Psychopathol. 2005 Summer;17(3):679-97 Findings There is strong evidence for a genetic basis of autism, although autism risk genes have not yet been identified. Autism spectrum disorders (ASD) involve at least three different symptom domains: social, communication, and restrictive behaviors/flexibility. The presentation is extremely heterogeneous, making it likely that multiple susceptibility genes are involved. In addition, many studies have shown that relatives of individuals with autism display some autism related impairments at a rate higher than that seen in the general population, and while they do not meet the threshold of autism, this is referred to as the “broader autism phenotype”. The authors discuss the likelihood that autism susceptibility genes do not cause autism per se, but rather increase the chance that an individual will develop one or more components of the syndrome. If an individual has multiple genetic susceptibility traits, they may develop “full-blown” autism. Past studies have analyzed specific autism characteristics to determine those with the highest heritability, and therefore the most promising for gene mapping. The investigators in this study focused on face processing ability as a potential neural marker for autism susceptibility. Many of the social impairments of autism such as eye contact, joint attention, and face recognition rely upon the ability to attend to and process faces, so it is not surprising that individuals with autism have been shown to have impairments in face processing. For this study, verbal, visual-spatial and face processing abilities of 143 parents of children with autism were measured. The parents exhibited significant difficulty in face recognition ability compared to their verbal and visual-spatial abilities. A subgroup of 21 parents from the group and 21 control parents also participated in an experiment to measure their response to face and non-face stimuli. Parents of children with autism showed an atypical response to face stimuli which mirrored the pattern shown by individuals with autism, i.e. slower than expected processing of faces and abnormal cortical specialization of face processing. Conclusions The authors suggest that abnormal face processing ability is a functional neural trait marker for autism. They note the importance of identifying and defining neural trait markers for susceptibility to autism so that autism risk can be identified early and interventions that target the specific domains can be initiated while the brain systems supporting these domains are developing and most easily molded.
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