Abstract
Rapid resumption refers to an observer's ability to rapidly resume a visual search following an interruption (Lleras, Rensink & Enns, 2005; 2007). Lleras et al. proposed that this ability stemmed from observers having performed some perceptual processing of the target based on the display information before the interruption, even though this pre-processing did not reach conscious awareness and thus did not allow participants to respond until after the search display had been re-presented. In Ahn and Lleras (VSS 2007) we showed that the pre-processing did not involve visuo-spatial working memory resources, since loading visuo-spatial working memory did not lead to a reduction in rapid resumption rates, even though it lead to slower response times overall. The present study explored whether executive working memory is involved in the perceptual pre-processing of the target. To do so, we manipulated the executive working memory load while participants performed an interrupted search task. In the dual-task condition, participants had to re-order 4-randomly chosen letters while they completed the interrupted visual search task, and performance was compared to a single-task condition in which participants only performed the interrupted search task. Our results showed that in the dual-task condition, response times were substantially delayed compared to the single-task condition. This detrimental effect of executive memory load was only found when observers were asked to perform the reordering task, and was absent in a control condition in which participants simply had to maintain the information in verbal working memory, which did not require the use of executive working memory. In spite of a general slowed down in response times in the dual task condition, the proportion of rapid resumption responses was unaffected by this working memory load, paralleling the results of Ahn & Lleras (2007) with visuo-spatial working memory.