Abstract
Working memory (WM) is critical for goal-directed behavior. The relationship between the storage of task-relevant items (declarative WM) and task rules (procedural WM) has been under debate, as some studies argue that they are independent while others propose they are interdependent. We aimed to test these rival accounts by investigating the effects of reactivating task rules on the reactivation of task-relevant items. For this, we used contralateral delay activity (CDA), a well-studied EEG index of WM load, to track WM storage of task-relevant items. Participants (N = 34) were given a visual item to be stored for a recognition or a size comparison task. Each item was repeated across six trials to enable its handoff to LTM. On some item repetitions, the task rule changed. These trials allowed testing the effect of updating task rules on the reactivation of task-relevant items. First, we found a significant CDA for novel items, which confirms that novel items are stored in WM. Second, the CDA amplitude decreased with target repetitions suggesting the handoff of WM items to LTM. Importantly, CDA was larger on task-switch compared to task-repeat trials. This result suggests that reactivation of task rules triggers the reactivation of task-relevant items in WM. By demonstrating that WM reactivation of LTM is interdependent for task rules and task-relevant items, this study informs our understanding of visual WM and its interplay with LTM.