Sensory integration is a normal neurological process of organization of sensations for use in our everyday lives.

The process of sensory integration underlies the development of all motor and social skills and the ability to perform daily living tasks. The process involves the brain’s ability to organize and make sense of different kinds of sensory information entering the brain at the same time. Sensory integration is manifested by the ability to produce an adaptive response. The primary sensory systems involved in the process come from the vestibular, tactile and proprioceptive systems.

All three sensory systems play a major role in the development of muscle tone, body posture, motor coordination, body scheme and awareness, and maintenance of a balanced level of alertness. When any or all of the systems are not working properly, individuals may display particular behaviors indicative of SI dysfunction. Sensory integrative dysfunction may be the result of a variety of problems. Messages may be improperly interpreted by the brain; specific sensory systems may not be responding appropriately; messages in the brain may be relayed too slowly or incorrectly; or messages may not be inhibited properly, causing the individual to become overwhelmed or under-aroused.

Key special senses for sensorimotor integration are:

Vestibular sense – The vestibular/cochlear receptors are located in the inner ear and are stimulated by movement, sound and input from other sense receptors. The vestibular/cochlear system affects:

• Balance
• Muscle tone
• Reticular activating system (alertness, learning and motivation)
• Intersensory information – process information from all other senses, such as smell, taste, vision, touch, hearing, and joint and muscle sensation.
• Bilateral integration – coordination of both sides of the body and development of hemispheric specialization) necessary to successfully hold paper and cut with scissors or write with a pencil)
• Oculomotor/visual perception – both eyes must work together in a smooth, coordinated manner to follow a line for reading. Weak neck muscles and poor head stability affect the development of normal smooth eye movement. Many areas of the brain must work together to make the meaning of what is seen.
• Auditory language center – the vestibular/cochlear system contributes to the development of understanding words and speech content. The individual is able to hear but has difficulty with listening.

"The process of sensory integration underlies the development of all motor and social skills and the ability to perform daily living tasks."