Abstract
Visual working memory has been demonstrated to be flexibly distributed across sample items depending on each item’s priority (Emrich, Lockhart, Al-Aidroos, 2017). This ability to flexibly prioritize information may depend on attentional control (Salahub, et al., in-press), which is the ability to select goal-relevant target information and suppress goal-irrelevant non-target information from entering visual working memory. To test this hypothesis, we examined flexible prioritization in a group of older adults, a population known for impairments in attentional control. Participants performed a delayed-recall task in which the number and validity of simultaneously presented spatial cues was varied. On some trials, memory load was manipulated by presenting 1, 2, or 4 cues with 100% validity. In the flexible prioritization condition, 1 item was cued with a 50% valid cue. Errors were modeled with the three-component mixture model to distinguish precision, guess-rate, and non-target errors (Bays, Catalao, & Husain, 2009). In a sample of older adults (ages 65-85), recall precision was consistently lower, and guess-rate was consistently higher than in a group of young adults (ages 18-30) across all conditions. Importantly, older adults, but not young adults, also made significantly more swap errors when flexible prioritization demands increased but memory load remained constant. This deficit was most evident under the highest flexible prioritization demands: when an un-cued item was probed. These results suggest that flexible prioritization is impaired in those with reduced attentional-control. Moreover, these findings are consistent with work showing that working memory impairments observed in older adults are due to a mis-allocation of resources (Hasher & Zacks, 1988; Gazzaley et al., 2005).