Normal eye drift and saccadic drift correction in darkness

Abstract

Eye drift at direct forward and lateral gaze angles in darkness, and concurrent saccades were examined in 15 normal subjects. Gaze dependent (centripetal) and constant (unidirectional) eye drift were found; four subjects had no systematic eye drift.

In darkness, the appearance of saccades in an opposite direction to that of the eye drift was dependent upon drift velocity, and not upon the total amount of eye deviation. Drift velocities over 0.6 deg/ s were regularly accompanied by 'countersaccades', whereas during lower drift velocities deviations up to 15 deg were not interrupted by saccades.

Key Words:

• eye drift
• normals
• saccadic correction