Abstract
Representations maintained in visual working memory (VWM) can exist in either an "active" or "accessory" state such that an item in an active state can interact with attentional guidance, but an item in an accessory state cannot. Frequent attentional capture by VWM-matching items under one-item memory load suggests that item is in an active state, but it is unclear whether the states of multiple items in VWM will be active, accessory, or a mixture of the two. Extant studies have relied on continuous variables like manual response times (RTs), and the subsequent results might obscure capture – especially if VWM representations cycle through active and accessory states. Unlike RTs, oculomotor capture provides a discrete measure – did the first eye movement go toward the target or the distractor? Therefore, we examined oculomotor capture by VWM-matching distractors under both high and low VWM load. Participants were presented with one or two colored squares to remember, then asked to saccade to a left/right target disk while eye movements were recorded. Once the target disk was fixated, participants completed a forced-choice memory test. On some trials, a distractor disk appeared above/below central fixation simultaneous with the target. Either the target or distractor could appear in a VWM-matching color. Eye movements were more frequently directed to a VWM-matching distractor compared to a non-matching distractor both with a one-item (28% vs. 7%; t(18)=5.60,p< .001) and two-item (13% vs. 8%; t(18)=3.97,p< .001) memory load. Critically, when multiple items were maintained in VWM, oculomotor capture by a VWM-matching distractor occurred, though at a reduced rate compared to a one-item memory load (13% vs. 28%; t(18)=5.67,p< .001). The current results suggest that, in absence of task demands to maintain both VWM items in an active state, only one item at a time was held in an active state.
Meeting abstract presented at VSS 2018