Programming saccadic eye movements.

R A Abrams; J Jonides

doi:10.1037//0096-1523.14.3.428

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Programming saccadic eye movements.

R A Abrams·J Jonides

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Abstract

This article addresses questions about the preparatory processes that immediately precede saccadic eye movements. Saccade latencies were measured in a task in which subjects were provided partial advance information about the spatial location of a target fixation. In one experiment, subjects were faster in initiating saccades when they knew either the direction or amplitude of the required movement in advance compared to a condition with equal uncertainty about the number of potential saccade targets but without knowledge of the parameters required to execute the movement. These results suggest that the direction and amplitude for an upcoming saccade were calculated separately, and not in a fixed serial order. In another experiment, subjects appear to have programmed the saccades more holistically--with computations of direction and amplitude parameters occurring simultaneously. The implications of these results for models of eye movement preparation are discussed.

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Attention Eye Movements Fixation, Ocular Humans Orientation Psychomotor Performance Reaction Time Saccades Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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R A Abrams, J Jonides. 1988. Programming saccadic eye movements.. https://doi.org/10.1037/%2F0096-1523.14.3.428

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