The effects of the visual system are farther reaching than most realize. Vision is not an isolated system, it is inseparable from the brain and the brain is inseparable from the body. This concept is essential to the understanding of how the vestibular system and vision are related. The vestibular system is what gives you your sense of balance and an awareness of your spatial orientation. It is a sensory system located in your inner ear that coordinates movement with balance. According to the Vestibular Disorders Association, we are able to successfully navigate our physical world because of the integration of the vestibular, visual, and proprioceptive (information perceived through our muscles and joints) systems. Our vestibular system develops before our visual system, causing our movement to guide our vision in the first few years of life. But when the necessary visual skills are developed, vision guides movement.
The College of Optometrists in Vision Development states, “One way the visual and vestibular systems work together is via the vestibular-ocular reflex (VOR). When motion of the head is sensed by the vestibular sensors in the inner ear, the information is processed by the central nervous system. Signals are sent to the eye muscles which cause our eyes to move in the opposite direction. The result is a stable image on the retina.” A brain injury could result in a vestibular- ocular reflex dysfunction which can cause dizziness, imbalance, and an unstable binocular system. When this happens, there is a lack of integration between the vestibular and vision systems. Vision therapy can effectively integrate the two systems.
One way vision therapy works to integrate the two systems is through strengthening awareness of your peripheral vision. Most go through their daily routines without thinking twice about their peripheral vision. In fact, most children have no idea what it is. By becoming aware of and processing what you are seeing in your periphery, your spatial awareness increases. Not only does there need to be a balance between the visual and vestibular systems but also between the visual systems: the central processing system and the peripheral processing system. It is just as important to be able to clearly see what your eyes are pointed at as it is to be aware of your surroundings (think driving). In vision therapy, we work to balance out the two visual systems first, and once those are sufficient, we begin to incorporate vestibular work. We do this by including head movement, body movement, balance, filters, and prisms. By simultaneously working on movement and vision, the two systems become neurologically reconnected.
The Dynamic Vision Therapy Center has a great list of possible visual symptoms when the vestibular-ocular reflex is impaired:
• Uncontrolled, repetitive movement of eyes
• Issues with balance, coordination, depth perception, and visual acuity
• Objects appear to bounce
• Light sensitivity
• Difficulty looking at moving objects, rows of similar objects, lines of text, etc.
• Visual dependence:
o Additionally, with the lack of integration between the vestibular and visual system, the movement of objects near the individual can be mistaken for one’s own movement in space.
If any of the above sounds like you or your child, schedule a comprehensive vision evaluation with us today!