Nearly 90 percent of children with autism are estimated to suffer from sensory abnormalities, often hypersensitivities, to stimuli that a neurotypical individual could ignore. These hypersensitivities can, in principle, be caused by abnormally acute sensory capabilities. However, empirical data contradict this possibility; individuals with autism do not differ systematically from neurotypical controls in their sensory acuity. Pawan Sinha and his colleagues at the Massachusetts Institute of Technology plan to consider an alternative account of hypersensitivities in autism.
Our ability to habituate plays a key role in suppressing sustained stimulation. It follows that reduced habituation would reduce stimulus suppression. Immersion in an unrelentingly salient stimulus would lead to a sense of being overwhelmed. Thus, the aversion to environmental stimuli that individuals with autism exhibit could arise from reduced habituation.
Sinha and his group propose to undertake experiments to rigorously test the hypothesis that autism is associated with reduced habituation. Their findings could have a significant impact on our understanding of a prominent aspect of the autism phenotype, and could also inform the design of novel kinds of early diagnostic tests.