Unisensory and Multisensory Disruptions in Autism Spectrum Disorders

SENSORY OBSERVATIONS IN AUTISM One insight into the sensory disturbances in autism comes from autobiographical reports. For example Temple Grandin, a well known highfunctioning professor with autism, describes her hearing experiences as “like having a sound amplifier set on maximum loudness.” Other reports indicate difficulty for individuals with ASD to process stimuli from multiple senses concurrently which often results in “sensory overload.” Retrospective analysis of home videos of infants who would later be diagnosed as autistic have found symptoms of abnormal reactions to sensory stimuli indicating that sensory disruptions are present even before a diagnosis is made. One strategy for quantifying sensory disturbances in ASD which has been used extensively since 1977 is the sensory questionnaire. These questionnaires are administered to parents or caregivers and usually include items on all modalities and varying reactions to stimulation in each modality (i.e. aversions and fascinations). These studies have shown that abnormal reactions to sensory stimulation as reported by parents are nearly universal in ASD with estimates up to 90% of individuals with ASD showing sensory symptoms. These studies have also shown that sensory disruptions are present in multiple modalities and include both hypoand hyperresponsiveness to stimulation. Collectively, this literature represent the entire range of both age and ability in autism indicating that sensory disturbances are an integral component in autism. Although this literature is vital in describing and quantifying abnormal reactions to sensory stimulation, it does not provide any information as to the underlying mechanisms of sensory disruption in ASD.