It is estimated that nearly 90% of all children on the autism spectrum suffer from sensory abnormalities, often hypersensitivities, to stimuli that a neurotypical individual could easily ignore (Leekam et al., 2007). 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 (DePape et al., 2012; Bölte et al., 2012). Here we consider an alternative account of hypersensitivities in autism. We hypothesize that autism is associated with reduced habituation, which in turn leads to reduced stimulus suppression. Immersion in an unrelentingly salient stimulus would lead to a sense of being overwhelmed. In this proposal, we describe experiments to rigorously test this hypothesis across multiple sensory modalities, and present preliminary data. This hypothesis can have significant impact on our understanding of a prominent aspect of the autism phenotype, and also help design novel kinds of early diagnostic tests.
With this motivation, our specific aims for this project are: 1. To investigate habituation in multiple sensory modalities in individuals with autism 2. To develop a quantitative measure of habituation and correlate it with scores from standardized autism tests pertaining to severity and sensory profiles 3. To study habituation across early development in NT and ASD children 4. (Contingent on results from aim 1) To explore the factors underlying reduced habituation in autism
Interagency Autism Coordinating Committee (IACC)
Autism Research Database (AFD)
