Asymmetric learning of dynamic spatial regularities in visual search: facilitation of anticipated target locations, no suppression of predictable distractor locations

Abstract

Static statistical regularities in the placement of targets and salient distractors within the search display can be learned and used to optimize attentional guidance. Whether statistical learning also extends to dynamic regularities governing the placement of targets and distractors on successive trials has been less investigated. Here, we applied the same dynamic cross-trial regularity (one-step shift of the critical item in clock-/counterclockwise direction) either to the target or a distractor, and additionally varied whether the distractor was defined in a different (color) or the same dimension (shape) as the target. We found robust learning of the predicted target location: processing of the target at this (vs. a random) location was facilitated. But we found no evidence of proactive suppression of the predictable distractor location. Facilitation of the anticipated target location was associated with explicit awareness of the dynamic regularity, whereas participants showed no awareness of the distractor regularity. We propose that this asymmetry arises because, owing to the target’s central role in the task set, its location is explicitly encoded in working memory, enabling the learning of dynamic regularities. In contrast, the distractor is not explicitly encoded; so, statistical learning of distractor locations is limited to static regularities.Public significance statementCan we learn the cross-trial dynamic regularity of a target or a task-irrelevant salient distractor (e.g., one-step shift of the critical item in clock-/counterclockwise direction) to boost search performance? The present study found robust learning of the predicted target location, but no evidence of proactive suppression of the predictable distractor location. Facilitation of the anticipated target location was associated with explicit awareness of the dynamic regularity. This asymmetry highlights the important role of the target-centered task set in the learning of dynamic regularities.

Learning regular cross-trial shifts of the target location in serial search involves awareness – an eye-tracking study

“…When the target was a bottom-up salient shape-singleton item (among differently but homogeneously shaped non-target items), summoning focal attention automatically, participants were able to extract the dynamic target-to-target location shift across trials, as evidenced by facilitated responding to targets at the new, predictable location (compared to targets at non-predictable, random locations). This is consistent with our own study (Yu et al 2023), in which the search target could also be detected and localized ‘in parallel’; we, too, found that search was facilitated when the target moved predictably across consecutive trials to the neighboring position in either clockwise or anticlockwise (blocked) direction – a somewhat simpler dynamic regularity compared to that introduced by Li and Theeuwes (2020). 1…”

“…Chun and Jiang 1998), Giménez-Fernández et al (2020) found that many participants were actually aware of the target’s unequal ( static ) spatial distribution. In a recent study of dynamic target-location probability cueing in pop-out search (Yu et al 2023), we likewise found a substantial number of participants to be explicitly aware of the dynamic (cross-trial) target regularity, and we observed the dynamic target-location probability-cueing effect to be significant only in the group of aware participants.…”

“…More recently, there have been several attempts to extend the study of probability cueing from scenarios with static target and, respectively, distractor distributions to dynamic scenarios, the question being: would statistical learning of selection priorities also work with ‘regular’ – that is, predictable – changes in the likely locations of targets or distractors across trials (Li and Theeuwes 2020; Li, Bogaerts, and Theeuwes 2022; Yu et al 2023). Together, these studies showed that attentional selection can successfully adapt to such dynamic, cross-trial regularities in the placement of target items: reaction times (RTs) were faster to targets appearing at the location predicted by the dynamic rule, compared to random locations (Li and Theeuwes 2020; Yu et al 2023). Importantly, though, Li et al (2022) found this to critically depend on search being spatially parallel, operating simultaneously across all display items (their Experiment 2b) – rather than serial, proceeding in an item-by-item manner (their Experiment 1), in which case no dynamic cueing effect emerged.…”

“…However, the idea that probability cueing is implicit in nature has come under scrutiny with studies using more sophisticated awareness measures to probe the relationship between explicit awareness and the cueing of target locations (van Moorselaar and Theeuwes 2023; Huang, Donk, and Theeuwes 2022; Yu et al 2023; Golan and Lamy 2023; Giménez-Fernández et al 2020; Vicente-Conesa et al 2021). The conflicting indications regarding a role of awareness in the learning of static target regularities may arise from a variety of factors, such as the probability levels used in the various studies, the number of trials, and the method employed to assess awareness (Jan Theeuwes, Bogaerts, and van Moorselaar 2022).…”

“…The present study re-investigated whether dynamic regularities may be learned in serial search when regular shifts of the target location occur frequently, and whether such learning would correlate with awareness of the dynamic rule. To this end, we adopted the same regularity used by Yu et al (2023) to demonstrate dynamic learning in parallel search: a cross-trial shift of the target location in, e.g., clockwise direction within a circular array in 80% of the trials, which was compared to irregular shifts in the opposite (e.g., counterclockwise; 10%) or some other, random direction (10%). The results showed that ⅔ of participants learned the dynamic regularity, with their performance gains correlating with awareness: the more accurately they estimated how likely the target shifted in the frequent direction, the greater their gains.…”