What is the theory behind it?

On a daily basis, most people experience events that simultaneously stimulate more than one sense ⁽⁵⁾. We use our multiple senses to take in this varied information, and combine them to give us a clear understanding of the world around us. We learn during childhood how to do this ⁽⁶⁾. Thus, through childhood experiences we gain the ability to use all of our senses together to plan a response to anything we notice in our environment ⁽⁵⁾. Children with autism are less capable of this kind of synthesis and therefore they may have trouble responding appropriately to differently stimuli.

Children with autism may also have a difficult time listening when they are preoccupied with looking with at something. This is an example of their difficulty in receiving information via more than one sense simultaneously ^{(5, 7)}. Physicians who treat children with autism believe that these difficulties are the result of differences between the brains of children with autism and other children ^{(5, 7, 8)}.

The underlying concepts of sensory integration therapy are based on research in the areas of neuroscience, developmental psychology, occupational therapy, and education ^{(1-3, 9)}. Research suggests that sensory information received from the environment is critical; interactions between the child and the environment shape the brain and influence learning. Furthermore, research suggests that the brain can change in response to environmental input, and rich sensory experiences can stimulate change in the brain.