The influence of visual perception on working memory throughout the adult lifespan

Previous studies show bidirectional interference between visual working memory (VWM) and ongoing perception, consistent with the common recruitment of perceptual cortical areas (Teng & Kravitz, 2019) in tasks requiring the maintenance of visual detail. Here, we hypothesized that the strength of the maintained representation in perceptual areas will degrade with age. In two experiments, five groups of participants, divided by decade (ages 20 to 69), were asked to maintain a memory cue (Experiment 1: circle color; Experiment 2: Gabor orientation) while performing a detection task in which a sequence of letters appeared on a task-irrelevant background (Experiment 1: color distractor; Experiment 2: Gabor distractor). Following a white letter detection task, participants reported the maintained memory cue using a continuous report. Similarity between the maintained memory cue and the task-irrelevant background (0º, 15º, 35º, 55º, or 75º) was manipulated. For each similarity condition, we measured the bias of the response from the memory cue towards the task-irrelevant background and the standard deviation of the error distribution that conveys the quality of the representation. We replicated previous findings in both experiments, showing that perceived information affects memory representation. As the similarity between the memory cue and the distractor background increased, so did the bias and standard deviation. Additionally, in Experiment 1, which examined memory for color, we found a greater amplitude of bias toward the task-irrelevant background and a larger standard deviation with increasing age. Memory for orientation, however, did not interact with age. Together, these findings identify a very specific way in which VWM degrades with age, pointing to a stronger decrease in the fidelity of memory representations for color than orientation.