Saccadic eye movements to peripherally discriminated visual targets

J Exp Psychol Hum Percept Perform. 1982 Feb;8(1):113-26. doi: 10.1037//0096-1523.8.1.113.

Abstract

Two experiments required subjects to identify a peripheral target embedded among nontarget stimuli and fixate it as quickly as possible with a single saccadic eye movement. Experiment 1 varied both the target distance and its angular position between trials; the mean oculomotor latency, the proportion of erroneous movements, and the proportion of (correct) movements followed by a corrective saccade all increased as a function of target distance. Experiment 2 held target distance constant (12.7 degrees) and used verbal instructions to manipulate the speed and accuracy of the subject's oculomotor performance between conditions. The speed/accuracy trade-off was similar for all subjects. The reduced uncertainty about target distance in Experiment 2 made each subject's oculomotor performance more efficient. Error trials not only included apparent perceptual errors (initial movements to nontarget stimuli) but also motor errors - that is, instances when the initial erroneous movement was followed, with an extremely short latency, by a large saccade to the target. The characteristics of these motor errors suggest that the saccade is not planned in terms of its amplitude and direction in retinal coordinates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Discrimination Learning
  • Distance Perception
  • Eye Movements*
  • Female
  • Form Perception*
  • Humans
  • Male
  • Reaction Time
  • Saccades*
  • Visual Fields*