How do individuals direct attention to valuable information in working memory tasks? Evidence from eye-tracking

There is now robust evidence that individuals can direct their attention towards particularly valuable information in working memory. However, the cognitive mechanisms underlying such effects are still under debate. One possibility is that participants preferentially encode high value information, creating a stronger representation relative to other information presented. We tested this hypothesis in two experiments. Participants completed a visual working memory task, which involved remembering the color of shapes for a brief period of time. During the encoding phase participants’ eye movements were recorded to assess fixation behaviors. Participants were then presented with one shape and asked to report the color as accurately as possible on a color wheel. In Experiment 1, participants were either told that one particular item was more valuable (i.e., worth more notional points than the rest), or that all items were of equal value. In Experiment 2, each item differed in its value in a graded manner (i.e., 1-2-3-4 points). Across both experiments, participants exhibited the lowest recall error for the highest value information. Moreover, participants spent significantly longer fixating on high value items during the encoding phase relative to other information presented. Further, the extent to which participants fixated on an item during encoding partially mediated the effect of value on recall error. Taken together, these experiments demonstrate that participants vary their eye movements during encoding as a function of value, and suggest that value-driven prioritization effects in working memory are partially driven by such behaviors.