Sensory integration (SI) is a theory and technique developed by A. Jean Ayres, a psychologist and occupational therapist. Ayres described SI as “the organization of sensation for use” (Ayres, 1979). In sensory integration theory, SI is referred to as a neurological process that occurs naturally within the brain with little conscious effort or attention. It involves the processing and integration of external and internal sensory information within the brain, and the ability to use this information functionally through appropriate adaptive responses. The sensory information that is received into our nervous systems from our environment or from within our bodies includes not only the senses most people are familiar with auditory (hearing), visual (seeing), olfactory (smell), gustatory (taste), tactile (touch), but also other sensations that arise from within our bodies, such as vestibular (movement) and kinesthetic/proprioceptive (where we are in space) sensory input. It is believed that the process of integrating all of our senses has an impact on our development, motor control, learning, and behavior.
Efficient organization of sensory information provides the foundation for the development of functional skills. Sensory Integration is used to describe certain processes that go on in our brain, allowing us to make sense of the information we get from our environment and act on it. The term refers to the process by which the brain interprets and organizes various sensory experiences including sight, sound, smell, touch, movement, body awareness, and the pull of gravity.
Sensory integration is a normal phenomenon of central nervous system functioning and provides a foundation for more complex learning and behavior. For some individuals sensory integration does not develop as efficiently as it should. Sensory integration dysfunction can result in motor development difficulties, learning difficulties, or behavioral concerns.
A disruption in sensory processing can result in sensory defensiveness (sensory seeking or sensory avoiding behaviors) problems in self-regulation (activity levels too high or too low for the task at hand), and difficulties with praxis (the ability to conceive, organize and execute skills of all kinds). Disruptions in processing sensory information can interfere with self-care skills, language skills, motor skills, academic skills, and social/emotional skills.