ABSTRACT

Sensory processing is defined as the coordination and integration of the sensory inputs received by the brain through the tactile, visual, auditory, olfactory, gustatory, vestibular, proprioceptive and interoceptive senses, and generating appropriate responses. Although interpersonal differences in sensory processing exist among healthy individuals, specific differences in sensory profile and sensory processing problems are encountered in some of the psychopathologies. Variations in sensory processing and associated clinical conditions are present among many neurodevelopmental disorders (NDDs) including principally autism spectrum disorder and others such as attention-deficit/hyperactivity disorder, intellectual disability, tic disorder and Tourette’s syndrome. In this article, studies on sensory processing in NDDs are reviewed. According to studies; symptom severity, comorbidities, adaptive behaviors, functionality, daily life activities, and participation in activities are associated with sensory processing differences and difficulties in NDDs. The sensory processing difficulties are posited to be based on differences in the activity of peripheral and central sensory systems. Neurophysiological and neuroimaging studies have tried to explain and enlighten the mechanisms underlying these problems. In this context, the main mechanisms are thought to be related to somatosensory inhibition, sensory gating, multiple sensory integration defects, and differences in gamma aminobutyric acid concentrations. There have been an increasing number of recent studies on sensory processing in NDDs. In this field, further randomized controlled studies supported by neurophysiological and neuroimaging techniques are needed. Due to the relationships between sensory processing features and the clinical symptoms of NDDs that they accompany, those features should be borne in mind in clinical evaluations and in treatment programs of children and adolescents.