The fate of visual working memory items after their job is done

Visual working memory is a competitive, capacity-limited system for the storage of feature and object-based information. In change-detection tasks, items are encoded into memory and, after a retention period, are compared against a test set. Loss of information can occur from attentional interference or prioritizing some items over others. But what happens to the memory representations after the change-detection task is completed? The current article examines the fate of a memory item after its behavioral purpose has been fulfilled. Participants encoded a single item in memory for a difficult change-detection task. Visual search trials were presented both before and after the memory test was completed. Singleton distractors were present in these search trials that could match or not the memory item. In Experiment 1, memory-driven capture (the memory-matching distractors led to longer search response times than the unrelated distractor) was observed in the pre-memory test and, in a weaker form, the post-test search trials. In Experiment 2, we introduced cues that indicated the memory test would not occur on a subset of trials, controlling for re-exposure to the memory stimulus. Memory-driven capture was again observed for these post-cue search trials, but only at a short time interval, at a longer interval this effect was attenuated. These results suggest that the memory representations only linger briefly in the visual system.