Formally known as sensory integration dysfunction, sensory processing disorder (SPD) is a neurological condition in which the brain has difficulty receiving and responding to sensory information (e.g., smell, touch, taste, etc.) that an individual perceives, thus, resulting in atypical responses.
Individuals with SPD can be hypersensitive (over responsive) and or hyposensitive (under responsive) to things in their environment. For example, some sounds may be painful or overwhelming to a child, but the child could not be responsive to touch and would seek tactile input by crashing into objects or people. SPD exists on a spectrum, like many illnesses. Children are typically considered for an SPD diagnosis when a child has atypical responses that begin to affect normal functioning and disrupts their everyday life.