Comparison of vestibular subjective sensation and nystagmus responses during computerized harmonic acceleration tests.

A comparison was made between the phase of vestibulo-ocular reflex (VOR) responses to sinusoidal rotatory tests and the phase of the subjective sensation (SS) to rotation. A parallelism was found between the results of both sets of data such that they behaved in accordance with the prediction of the pendulum model of vestibular function. The time constant of the VOR (17.5 seconds) was longer, however, than that of the SS (13 seconds). Measurements in patients with unilateral labyrinthine pathology also showed comparable changes in both responses. One group of patients with complete unilateral labyrinthine paralysis showed an advance of the phase of the VOR and of the SS. However, phase measurements in the group of patients with only partial unilateral labyrinthine paralysis were not significantly different statistically from those of normal subjects.