Does Memory-driven Attentional Capture Happen Automatically?

Currently there were mixed evidence on whether the contents of working memory could influence visual attention. The studies in whether working memory contents could affect the deployment of attention in visual search had reported conflicting results. The present study was designed to address this discrepancy and figure out the influence of the so called "strategy" or "cognitive control" on memory-driven attentional capture, by solving this question:the way working memory contents capture attention in visual search.Experiment 1 was designed to explore the way working memory contents capture attention in visual search by the use of an arrow cue, which would indicate in which side of the search filed the target would appear (either left or right side) before the search task. From Experiment 1, we found strong evidence that attention was captured by the matching distractor even when it was presented at the opposite side of the target. The results also showed that this capture might take place in the early stage of the search task, which means the memory-matching distractor might capture attention immediately after the onset of the search task. And this process could not be override by cognitive control, it was inevitable. The finding that RTs were equally the same between invalid-inconsistent and invalid-consistent conditions, suggested the effect of memory-driven attentional capture should be mainly caused by this early capture.The goal of Experiment 2 was to address the limitation of Experiment 1 and provide a stronger test of the results from Experiment 1. To achieve this, a new cue was employed in Experiment 2, which would indicate not only in which side of the search filed the target would appear, but also the possible target locations. The results of Experiment 2 yielded even stronger evidence that the memory-matching distractor could strongly capture attention right after the onset of the search task. And this also showed the contents of working memory had robust effects on the deployment of visual attention.Experiment 3 was designed to rule out the remote possibility that the memory-driven attentional capture found in our experiments might be mainly caused by the occasional capture of attention by the matching distractor presented at the opposite side during the search task, rather than the capture of attention by the matching distractor at the very beginning of the search task, in which a distractor (either a memory-matching distractor or a neutral distractor) presented at the opposite side would turn gray in a short time (300 ms or 500 ms) after the onset of the search task. Thus any effect caused by the matching distractor would be limited in this period of time. The results showed that the matching distractor could still capture attention even when it turned gray 300 ms after the onset of the search task. This finding also confirmed our hypothesis that the contents of working memory could affect the deployment of attention immediately after the onset of the visual search task.In conclusion, the contents of working memory had robust effects on the deployment of visual attention. And this process tended to take place at the early stage of the search task, which could not be override by cognitive control or the so called "strategy".