Abstract: Many studies addressed the interaction between working memory (WM) and selective attention. However, these studies mostly concerned with the voluntary or endogenous mechanisms of selective attention and little is known about the relationship between WM and involuntary attention. Moreover, by investigating the relationship between WM and involuntary attention, we could get a deeper understanding of the cognitive control mechanism of WM. Therefore, the present study aimed to examine how WM impact involuntary attention by manipulating the WM load. Meanwhile, in order to examine the load theory of selective attention, we adopted verbal WM task and spatial position discrimination task to avoid the competition of perceptual attentional resource between WM and selective attention. The spatial position discrimination task demanded participants to discriminate the position (left versus right) of a dot presented in a square. In half of these trials, visual distraction produced by a “pop-out” red Korean presented from one of the four side of the square. In the verbal WM task, a numeric string of 3-digits, 5-digits or 7-digits (low, middle and high WM load conditions, respectively) was presented in random order and participants had to remember the order for report at the end of each trial. Participants made signi?cantly more recall errors in the high and middle WM load conditions than in the low WM load condition, demonstrating that the verbal WM load manipulation had been effective. Repeated-measures analyses of variance (ANOVA) for mean RTs of spatial position discrimination task showed that distraction effect was influenced by WM load: the distraction effect was significant under high WM load condition; however, it was not significant under low and middle WM load conditions. This indicated that the cognitive control resources was consumed by high load on WM and resulted in a failure of suppression of distraction, so the distraction effect was significant; while in the low and middle WM load conditions, subjects could assign resource to suppress the processing of distracters, so there was no distraction effect. This result supported the load theory of selective attention: load on WM would reduce the available resources for cognitive control and result in increased distractor processing.

Key words: working memory, load theory of selective attention, involuntary attention

摘要： 通过探讨工作记忆负荷对无意注意的影响，考察工作记忆的认知控制功能对选择性注意的作用机制。为了避免工作记忆和选择注意的目标或者干扰子之间的知觉注意资源的竞争，采用言语工作记忆任务和视觉空间位置辨别任务，同时视觉干扰刺激采用被试无法识别的韩语。结果发现，在高负荷条件下，干扰效应显著；而在低和中负荷条件下，没有观察到干扰效应。说明在高负荷条件下，被试没有额外的资源来抑制干扰加工，从而出现了显著的干扰效应。由此，本研究支持负荷理论的观点：工作记忆在选择性注意中执行认知控制功能。

关键词: 工作记忆, 负荷理论, 无意注意