Visual event boundaries trigger forgetting despite active maintenance in visual working memory

The contents of visual perception are inherently dynamic-just as we experience objects in space, so too events in time. The boundaries between these events have downstream consequences. For example, memory for incidentally encountered items is impaired when walking through a doorway, perhaps because event boundaries serve as cues to clear obsolete information from previous events. Although this kind of "memory flushing" can be adaptive, work on visual working memory (VWM) has focused on the opposite function of active maintenance in the face of distraction. How do these two cognitive operations interact? In this study, observers watched animations in which they walked through three-dimensionally rendered rooms with picture frames on the walls. Within the frames, observers either saw images that they had to remember ("encoding") or recalled images they had seen in the immediately preceding frame ("test"). Half of the time, a doorway was crossed during the delay between encoding and test. Across experiments, there was a consistent memory decrement for the first image encoded in the doorway compared to the no-doorway condition while equating time elapsed, distance traveled, and distractibility of the doorway. This decrement despite top-down VWM efforts highlights the power of event boundaries to structure what and when we forget.