Human express saccades: extremely short reaction times of goal directed eye movements

  title={Human express saccades: extremely short reaction times of goal directed eye movements},
  author={Burkhart Fischer and E. Ramsperger},
  journal={Experimental Brain Research},
SummaryHuman subjects were asked to execute a saccade from a central fixation point to a peripheral target at the time of its onset. When the fixation point is turned off some time (≈ 200 ms) before target onset, such that there is a gap where subjects see nothing, the distribution of their saccadic reaction times is bimodal with one narrow peak around 100 ms (express saccades) and another peak around 150 ms (regular saccades) measured from the onset of the target. Express saccades have been… 
Human express saccades: effects of randomization and daily practice
If the fixation point is turned off some time (200 ms) before the target is turned on, the distribution of the saccadic reaction times is bimodal and the proportion of express saccades increases with daily practice and their reaction times decrease slightly.
The time of secondary saccades to primary targets
Using the gap task with random target locations, it is found that large errors after anticipatory saccades — especially those after direction errors — can be corrected very fast.
Dead zone for express saccades
For small saccades the express way is blocked functionally or does not exist anatomically and their velocity falls above the main sequence as defined by the least square fit of an exponential v=vo(1-exp(-a/ao) to the maximal velocity (v) versus amplitude (a) relationship.
Visual processing of targets can reduce saccadic latencies
Express saccades: is there a separate population in humans?
Work is reported which confirms the existence of short latency visually guided saccades in humans but questions whether these form a separate population of “express saccade latencies”.
Further observations on the occurrence of express-saccades in the monkey
It appears that for an express-saccade to occur, the process of interruption of previous active fixation must be completed at the time when a new target becomes visible.
An examination of the variables that affect express saccade generation
Increasing the gap time between fixation spot termination and target onset increased express saccade frequency but was progressively less effective in doing so as the number of target positions in the sample was increased.
The differentiation of visually guided and anticipatory saccades in gap and overlap paradigms
It is shown that the latency of foveating saccades can be altered by changing the offset time of the current fixation point relative to the onset of the peripheral target by Saslow and others.
Influences of motor instructions on the reaction times of saccadic eye movements
Separate populations of visually guided saccades in humans: reaction times and amplitudes
The results suggest that, in the gap task, most of the naive subjects exhibit at least two clearly separated peaks in the distribution of the saccadic reaction times, which indicates that express saccades almost never overshoot.


Express-saccades of the monkey: Reaction times versus intensity, size, duration, and eccentricity of their targets
Comparison with response latencies of afferent visual neurons suggests that the dependence of the reaction times of express-as well as regular-saccades on the physical parameters of the target is mostly determined by retinal factors.
Express-saccades of the monkey: Effect of daily training on probability of occurrence and reaction time
The results indicate the existence of a fast-operating visuo-to-oculomotor pathway which can be quickly and reversibly modified by daily exercise.
Effects of components of displacement-step stimuli upon latency for saccadic eye movement.
  • M. Saslow
  • Biology, Psychology
    Journal of the Optical Society of America
  • 1967
The standard displacement-step stimulus often used to produce lateral saccadic eye movements is considered in terms of the effects of its components: termination of stimulation at an initial fixation
Saccadic eye movements after extremely short reaction times in the monkey
Two-dimensional eye movement monitor for clinical and laboratory recordings.