Recovery of Visual Acuity in People With Vestibular Deficits

Inclusion Criteria: * Patient had to have either a unilateral vestibular or bilateral vestibular hypofunction defined as follows: Unilateral vestibular deficits were defined by a \> 25% difference in slow phase eye velocity between right and left sides on either the caloric or rotary chair test. Bilateral vestibular deficits were defined included refixation saccades made in response to unpredictable head thrusts to the right and left, a gain \< .1 on rotary chair step test and a peak slow phase eye movement of \<5 degrees/sec during irrigation of each ear on bithermal water caloric testing * Healthy subjects with normal vestibular function test results * must be able to complete DVA test Exclusion Criteria: * Patients with central lesions will be omitted from the study because vestibular adaptation or other compensatory mechanisms may be compromised and * Patients with visual acuity when the head is stationary of 20/60 or worse. * Patients on medication that suppress or facilitate vestibular function will not be excluded from the study but data will be analyzed to assess the effect of medication. * Patient who do not understand the purpose of the study and what it involves