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. (c) 2005 Elsevier Ltd. All rights reserved.