The express saccade has been discovered in 1983 in the monkey and in 1984 in man.
Express saccades are a visually guided saccades that constitute an early mode (peak) around 70-80 ms in the monkey and around 100 ms in man in bi- or even trimodal distribution of saccadic reaction times.
The gap task favours express saccades, in the overlap task they are usually absent. Training can increase the frequency of express saccades, but they can be produced by naive subjects as well. Multimodality is not always observed, sometimes express saccades can occur as a single peak. Express saccades occur also as erratic saccades (prosaccades to the stimulus) in the antisaccade task.
The express saccade occurs as an optomotor reflex mediated by the tectal system. With the fixation system deactivated express saccades occur frequently. Attention (parietal system) and decision (frontal system) modulate the generation of express saccades.
Express saccades occur often as erratic prosaccades in an antisaccade task.
The neurophysiological basis of express saccade generation at the tectal level has been investigated by the group of Douglas Munoz at Queens University, Kingston, Canada.