Abstract
Salient non-targets usually interfere with target selection and produce increased reaction times (RTs) and lower accuracy (e.g. Posner, 1980). Here we demonstrate that a perceptually salient (i.e. high contrast) non-target can facilitate target selection in a visual search task, when it is predictable. Eye-tracking data indicate that this facilitation is due to better inhibition and faster non-target rejection when attention is captured. Inhibition was indexed by more first fixations away from the salient non-target as well fewer subsequent fixations on the non-target. Faster rejections due to attentional capture were indicated by shorter first saccade initiation times to the salient non-target followed by shorter dwell times once the non-target had been fixated. This effect of salient non-target facilitation was modulated by working memory such that higher visual short term memory loads produced less inhibition (more attentional capture) and less effective non-target rejection of the salient non-target. This suggests that working memory is essential for maintaining a representation of the salient non-target's task-relevance and initiating commands to move attention and the eyes away from it. We argue that while attentional capture by perceptually salient stimuli may be automatic, information regarding the current statistical relevance of that stimulus may be held in working memory and used to guide voluntary attention and maximize behavioral efficiency.