The vestibulo-ocular reflex in the cat during linear acceleration in the sagittal plane

Abstract

The horizontal and vertical components of the vestibulo-ocular reflex (VOR) were recorded in alert cats that were rotated with their head placed on or 45 cm eccentric from the axis of rotation. During off-axis rotation there was a centripetal acceleration along the animal's naso-occipital axis that changed the direction and the magnitude of the resultant otolith force in the animal's sagittal plane. When the animal was upright and eccentric from the axis of rotation, the horizontal VOR (HVOR) had a shorter time constant and smaller amplitude compared to the on-axis HVOR. The effect was symmetrical for both directions of the naso-occipital linear acceleration. When the animal was on its side and faced away from the axis of rotation, there was a decrease in the time constant of the down VOR. When the animal faced the opposite direction, the down VOR time constant was increased. No statistically significant effect was found on the amplitude of the VVOR and the time constant of the up VOR.