Sensory defensiveness in persons with developmental disabilities

Little empirical data about the nature of tactile defensiveness and other types of sensory defensiveness are available. Clinicians speculate that these various phenomena are related as part of the more general construct of sensory defensiveness. Furthermore, although it is suspected that these behaviors are prevalent in persons with developmental disabilities, no estimates are currently available. This study used data from a 54-item survey about various kinds of stereotyped and unusual behaviors completed by a large sample of adults (n=158) and children (n=88) with developmental disabilities. Six items from the survey were selected that were thought to represent types of sensory defensiveness. Estimates relative prevalence of these behaviors ranged from 3% to 30%. Developmental differences emerged; children in the sample displayed a higher prevalence of noise sensitivity and other, general sensitivity. Many of the items were significantly correlated with one another An initial principle component analysis provided some evidence for a general factor Of sensory defensiveness. A second principle component analysis with varimax rotation demonstrated two subtypes: ''Auditory/Other Hypersensitivity'' and ''Tactile Defensiveness.'' These findings elucidated the complexity of the structure of sensory defensiveness and have implications for occupational therapy assessment and treatment, particularly in the area of sensory integration theory.