T he vestibular system detects motion, gravity and provides us with our sense of balance. The system develops early in utero and through its many connections with the rest of the brain, it is believed to provide the foundation for many other functions. When the influences of vestibular stimuli fail to reach their natural destinations, they cannot adequately contribute to sensory integration.

Hypersensitivity to movement and fear of movement are both indicators of a vestibular disorder. Children who excessively crave movement and appear never to get dizzy also may have disorders of the vestibular system.

Muscle tone can also influenced by the vestibular system and when the vestibular system in not integrating information adequately it can contribute to hypotonia. Muscle tone is the normal level of muscle tension in the body at rest. If it is decreased it is more difficult to initiate movement or maintain tension of a muscle during movement. The person may appear more floppy. Muscle tone is necessary for good proximal stability, and a lack of sufficient postural support can contribute significantly to difficulties in fine/gross and oral motor coordination. All refined movements of the extremities and the head are dependent on an adequate base of muscle tone which provides postural support. The vestibular system provides the opportunity for the two sides of the body to communicate on the brain stem level. In this manner it supports the development of bilateral coordination, which is the ability of the body to use both sides in a coordinated manner. This in turn influences the development of laterality and the specialization of skills on each side of the body.

Position in space perception and visual perception is an end product of sensory integration and is particularly influenced by the vestibular system. The vestibular system has direct connection with the eyes so that the individual is able to know immediately if he/she or the environment is moving. This provides the stability for accurately interpreting information from our visual field. The perception of movement and gravity are central to the origin of space perception, and it appears that developmentally the visual system depends on the vestibular system to make sense out of what one sees. Difficulties with spatial orientation may be related to inadequate integration of information from the vestibular system.

The vestibular system is anatomically joined with cochlear system, and the systems lie closely together throughout the nervous system. This allows for many close neuronal associations with auditory processing and language. Decreased vestibular processing can impact on the area of speech and language development. Research has found that therapy to improve the function of the vestibular system can also result in improved language development.

The vestibular/cochlear system is involved in motivation and attention as it acts to transmit a cortical charge to the brain which enables the person to attend to and integrate sensory information from the vestibular system with other sensory information. It acts to integrate information from the vibration of movement and sound with touch, proprioception, and vision.