Abstract
Gaze stabilizing function during active head rotations at high frequencies was investigated in 12 normal adults. Head rotation amplitude decreased as the frequency increased, from 31° at 2 Hz to 11° at 5 Hz on average ; the corresponding maximum head velocity and acceleration amounted to about 170-200°/sec and 2500-5000°/sec2, respectively. At the frequencies higher than 2 Hz, the amplitude of compensatory eye movement exceeded head rotation amplitude ; the mean ratio of the former to the latter increased linearly from 1.19 at 2 Hz to 1.80 at 5 Hz.
The present study indicated that the compensation for head rotation by the vestibulo-ocular reflex, which is adapted in daily experienced head movements, deteriorates quickly as head oscillates over this functional range.
