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Leo Trottier

Publications and source records attributed to Leo Trottier.

2 recordsLinked to original sources

Pro-saccades and anti-saccades to onset and offset targets.

Pro- and anti-saccades made to either onset or offset targets were examined to determine which of (1) changes in luminance or (2) the appearance of new peripheral objects, is more important in the reflexive generation of pro-saccades. In two experiments, pro-saccades had faster reaction times than did anti-saccades, but the difference was much greater for onset targets than offset targets (both with white targets on black backgrounds and black targets on white backgrounds). These findings suggest that there is a continuum of "prepotentness" in the oculomotor system with new peripheral objects being especially effective in generating reflexive pro-saccades.

Adolescent↗

Visual processing of targets can reduce saccadic latencies.

Normal human saccadic reaction times (SRTs) have been thought to be approximately 200 ms. The present study, using an experimental method that takes advantage of what the saccade system has evolved to do (by instructing subjects to rapidly acquire detailed visual information from the environment), shows that human SRTs are actually on the order of 150 ms. Moreover, when combined with the sensory-based "gap" effect (removal of gaze fixation object prior to target presentation), this method yielded extremely low SRTs. These findings imply that previous approximations of human SRTs may have been too conservative, and that the group of saccades often classified as "express" may instead represent the norm.

Adult↗