Saccadic trajectories change with amplitude, not time

Saccadic trajectories were examined in ten young normal subjects for amplitudes of 5,15,30, and 40 deg. Multiple saccades (m) and discrete decelerations (dd) were seen not in conjunction with any fatigue effect but rather as a function of amplitude, being much more frequent at larger amplitudes. The presence of m and dd in the large saccades of normals and in even small refixations of patients with myasthenia and Eaton-Lambert syndrome suggests that they are a normal consequence of high innervation levels.