The Effect Of Working Memory Load On Attentional Capture

Attentional capture is of great importance in revealing the relationship betweentwo kinds of attentional control: bottom-up process and top-down process. In thetraditional attentional capture researches, most of the researchers used additionalsingleton paradigm, paid more emphasis on the role of stimulus saliency in attentionalcapture, and attentional capture was purely stimulus driven process, while there werefew researches about the top-down cognitive control in attentional capture.Behavioural and neuroimaging studies showed that working memory providedgoal-directed control of visual selective attention. The cognitive control function ofworking memory serves to maintain current priorities between targets and distractorsand decreases distraction by goal-irrelevant distractors in selective attention. Thestudy explored the effect of working memory load on attentional capture, in order toprobe into the effect of top-down cognitive control and the effect of the stimulussaliency on attentional capture.Three experiments were included. The effects of single-task and dual-task onattentional capture of color distractors were compared in Experiment One. Whiledifferent working memory load on attentional capture of color distractors wereexamed in Experiment Two. And different working memory load on attentionalcapture of form distractors were explored in Experiment Three.Some major results were obtained. Firstly, the cognitive control function ofworking memory not only affected in selective attention but also in attentional capture.Secondly, attentional capture was not purely stimulus driven but was subject totop-down control. Thus, it was concluded that the higher working memory load, themore the effects of attentional capture produced by the irrelevant singleton. Thirdly,whether an irrelevant stimulus could capture attention or not, depended on the weightbetween the effect of stimulus saliency and the effect of top-down cognitive controlon attentional capture.In conclusion, working memory had the effect of cognitive control on attentionalcapture and whether an irrelevant stimulus could capture attention or not, dependedon the weight between the effect of stimulus saliency and the effect of top-downcognitive control on attentional capture.