Short-latency fixational saccades induced by luminance increments.
We investigated the effect of peripheral visual stimulation on small-amplitude saccades that occur naturally during fixation. Two macaque monkeys were rewarded for fixating while a colorful stimulus flickered randomly in the periphery. Reverse correlation revealed a lawful relationship between the stimulus sequence and saccade occurrences: on average, a transient increase in stimulus intensity evoked saccades at a latency of approximately 70 ms. The spectral tuning of this increase was roughly, but not exactly, consistent with a pure luminance increase. We conclude that peripheral luminance increases can evoke fixational saccades.
Horwitz
Gregory D
GD
Howard Hughes Medical Institute and Vision Center Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037, USA. horwitz@salk.edu
Albright
Thomas D
TD
D000818:Animals; D005403:Fixation, Ocular / Q000502:physiology; D008253:Macaca mulatta; D010775:Photic Stimulation; D012438:Saccades / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology