Question

People with vestibular dysfunction sometimes experience blurred vision. Why and how might this occur?

Answer 1

VESTIBULAR DYSFUNCTION:

The dysfunction or disorder in the Vestibular system which includes the parts of the inner ear and brain that works to control balance and eye movements is called vestibular dysfunction.

This vestibular system can get damaged by disease, aging or head injury which leads to vestibular disorders resulting in blurred vision, vertigo and dizziness. Genetic and environmental factors may also cause vestibular disorders.

Reason why Vestibular Dysfunction cause blurred vision:

The Vestibular system sends motor control signals to muscles of the eyes through the nervous system. This takes place with an automatic function called the vestibulo ocular reflex (VOR). This Vestibulo ocular reflex is important part in maintaining balance and clear vision. This controls eye positions so that gaze remains stable even when the head moves.

For example Vision system can be compared to photography. The camera must be held steady by photographer to produce clear picture, if not the picture will be blurry. Likewise malfunctioning vestibular system changes a person with good vision into blurred vision.

How vestibular dysfunction cause blurred vision:

Usually the eyes should work in perfect synchrony as the number of impulses transmitted from right side vestibular organs are equal to the number of impulses from the left side while head is not in motion but when head turns towards right the number of impulses transmitted through nervous system from right ear increases and the number of impulses from left ear decreases. The difference in impulses from each side controls eye movements and gives stable gaze in active head motions. Stable gaze has a predictable ratio. If the head rotates at one angle at certain speed, the eyes rotate with same speed but in the opposite angle or direction. Normally Both the ears provides symmetrical sensory information. But if there is a dysfunction in vestibular organs in one or both the ears the brain receives conflicting signals during movement or motion, resulting in blurred vision or vertigo or dizziness.