Presaccadic spike potential in normal subjects

We examined the characteristics of the presaccadic spike potential (SP) in normal human subjects to clarify some of the discrepancies between previously reported studies. Measurement of SP was performed in 14 normal human volunteer subjects performing saccades to visual stimuli. These were compared left versus right, centripetal versus centrifugal, and in increments of 5, 10, 20, and 40 degrees. SP amplitudes for saccades to center were greater than from saccades away from center at higher degrees. SP amplitudes to abducting saccades were of larger amplitude than those of adducting saccades. This study clarifies some discrepancies in previous reports on SP which did not distinguish saccades to center versus from center. SP data of normal individuals, for multiple saccade angles and directions, provides a basis for studying patients with disorders of ocular motility.