Elsevier

Vision Research

Volume 49, Issue 16, 12 August 2009, Pages 2045-2055
Vision Research

Attentional release in the saccadic gap effect

https://doi.org/10.1016/j.visres.2009.02.015Get rights and content
Under an Elsevier user license
open archive

Abstract

Can a release of attention from fixation help explain the saccadic ‘gap effect’, the shortening of saccadic latency (SL) when the fixation spot is extinguished just before saccade target onset? Practiced observers generated SLs and button-presses to one of four 10° eccentric targets in overlap (fixation spot stays on), gap0 (fixation offsets at target onset), and gap200 conditions; in gap200, the fixation spot was removed, dimmed, expanded, or brightened 200 ms before target onset. Our data excluded speed-accuracy trade-offs, express saccades, stimulus salience, and oculomotor readiness, while fixation offset and general warning had minor effects, leaving attention release as the default explanation. Supporting this notion, finger-press reactions to foveal probe dots presented after the fixation spot was brightened (to hold attention) were faster than those made after the spot was removed (to release attention). Varying the time from gap onset to the probe dot mapped out the time-course of the putative attentional release, which takes ∼140 ms.

Keywords

Saccades
Latency
Motor reaction times
Gap effect
Warning effects
Attention release

Cited by (0)