Abstract

Using a visual-persistence method described by Ginsborg and Maurice,¹ coupled with high-speed photography and eye-tracker records, we have explored the eye movements that take place during a blink. With straight-ahead binocular fixation each eye typically rotates nasalward and downward by 1° or 2° during the closing phase of a blink. The movements of the eyes are more rapid, however, than those of the lids. Maximum rotation of the eyes occurs slightly before lid closure is complete, and the eyes return to their initial positions well before the lids are fully reopened. Measurement of the direction, amplitude, and time course of such eye movements provides evidence for recent proposals that, with off-center viewing, a blink causes each eye to rotate toward its primary position of regard. Indeed, if the eye is already in that position when the blink takes place, there is scarcely any eye movement at all. In normal conditions of viewing there is no evidence of conjugate saccades or of any large upward rotation of the eyes (Bell’s phenomenon) that was formerly thought to take place during a blink.

© 1985 Optical Society of America