A Study Of P300 On The Attentional Boost Effect

Decades of work on dual-task performance and selective attention has provided clear and robust evidence that dividing attention(DA)during encoding generally impairs subsequent memory performance.However,recent research reports that detecting infrequent targets in a DA condition while simultaneously encoding a series of images into memory can enhance memory of images on subsequent memory test.This unusual phenomenon was labeled as the attentional boost effect(ABE).Jin firstly adopt ERP(Event Related Potential)technique to investigate the time course and psychophysiological processes underlying ABE,and found that target condition induced a larger P300(300-500ms)amplitude than distractor condition.Jin therefore proposed that the difference between target and distractor condition in the mean amplitude of P300 reflected the enhancement triggered by target detection.However,considering the P300 also related reflected the specificity of stimuli and the updating of working memory,in this study we designed two experiment to explore the relation between the P300 property in the attentional boost effect,the specificity of stimuli and the updating of working memory.In the experiment 1,we change the frequency of detection stimuli to control the specificity of stimuli,and found that the specificity of stimuli not only could moderate the memory advantage by target detection,but the P300 amplitude between the target and distractor condition.In the experiment 2,we control the load of working memory during the task operation process,and found that the load of working memory could moderate the advantage by target detection,but did not affect the difference of P300 amplitude between target and distractor condition.Those findings suggested that the specificity of stimuli and the load of working memory could influenced the ABE,and the P300 property of the ABE could partly reflect the specificity of stimuli,but the updating of working memory.