Blink‐induced saccadic oscillations

A patient with a neurodegenerative disease had abnormal saccades only when he blinked. These saccades were hypermetric and were followed immediately, without any intersaccadic interval, by a large, oppositely directed saccade (dynamic overshoot). To explain these findings, we hypothesize that a blink‐related neural signal can modulate the activity of pause cells that normally inhibit saccadic burst neurons during fixation. In pathological circumstances, abnormal function of pause cells could lead to large‐amplitude saccadic oscillations. In normal subjects, blinks could induce short bursts of low‐amplitude flutter.