Looking sharp: Becoming a search template boosts precision and stability in visual working memory

Abstract

Visual working memory (VWM) plays a central role in visual cognition, and current work suggests that there is a special state in VWM for items that are the goal of visual searches. However, whether the quality of memory for target templates differs from memory for other items in VWM is currently unknown. In this study, we measured the precision and stability of memory for search templates and accessory items to determine whether search templates receive representational priority in VWM. Memory for search templates exhibited increased precision and probability of recall, whereas accessory items were remembered less often. Additionally, while memory for Templates showed benefits when instances of the Template appeared in search, this benefit was not consistently observed for Accessory items when they appeared in search. Our results show that becoming a search template can substantially affect the quality of a representation in VWM.

Do we remember templates better so that we can reject distractors better?

“…While the difference between template and accessory memories was larger following heterogeneous searches in Experiment 2, Experiment 3 demonstrated that this was likely caused by differences in the opportunities for perceptual resampling. On the basis of these results, it seems most sensible to conclude that the template memory advantage we have observed in this task before (Rajsic et al, 2017) reflects the need to make a decision about the template color during search rather than an effort to improve the guidance of attention toward target-defining features and away from distractors during search. We should note as well that template memories could have, in principle, been sharpened during the difficult search as distractors were being rejected, and not in advance of the search.…”

“…When we look for one of two things we are remembering, our memory for what we looked for is better than our memory for what we did not look for (Rajsic et al, 2017). Here, we asked whether this is because we sharpen template memories so that we can later filter out distractors more effectively during search (the adaptive-weighting hypothesis) or because we need to respond affirmatively to a specific feature, once attended, and not others (the recognition-weighting hypothesis).…”

“…Recently, Rajsic, Ouslis, Wilson, and Pratt (2017) found that a consequence of assigning template status to a representation in working memory is that this memory can be reported with greater fidelity than an accessory memory. This was the case even when neither remembered color was encountered during search, suggesting that making a memory into a search template does not only prevent accessory items from interacting with visual attention, but shapes the memories themselves.…”

“…We ran two between-subjects conditions: a heterogeneous search and a homogeneous search. Borrowing from the design of Rajsic et al (2017), we had participants remember two colors on each trial. One was the target, which we call the template in following text, and the other was an item that they knew they would be tested as often, that we will call the accessory item in the following text (see Fig.…”

Distinct prioritization of visual working memory representations for search and for recall

“…The priority of items within a memory array is typically determined following clear task instruction, such as explicitly assigning an item template status (Carlisle, Arita, Pardo, & Woodman, 2011;de Vries et al, 2017;Rajsic, Ouslis, Wilson, & Pratt, 2017;Vickery, King, & Jiang, 2005;, or using cues to identify the item(s) most likely to be the object of a subsequent memory test (Dube et al, 2017;Emrich et al, 2017;Hollingworth & Hwang, 2013;van Moorselaar, Theeuwes, & Olivers, 2014, Experiment 4). Recently, it has been shown that identifying an item as a template for an upcoming search not only causes that item to bias attentional selection, but it also causes that representation to be encoded with greater precision than those items that are accessory (Rajsic et al, 2017). Across two experiments, Rajsic et al (2017) had participants encode two colored forms for a subsequent memory test, and a cue indicated which of the two items should serve as the template for an intervening search task requiring a present/absent judgment.…”