Feature-based guidance of attention by visual working memory is applied independently of remembered object location

Searching near and far: The attentional template incorporates viewing distance

According to theories of visual search, observers generate a visual representation of the search target (the "attentional template") that guides spatial attention toward target-like visual input. In real-world vision, however, objects produce vastly different visual input depending on their location: your car produces a retinal image that is 10 times smaller when it is parked 50 compared to 5 m away. Across four experiments, we investigated whether the attentional template incorporates viewing distance when observers search for familiar object categories. On each trial, participants were precued to search for a car or person in the near or far plane of an outdoor scene. In "search trials," the scene reappeared and participants had to indicate whether the search target was present or absent. In intermixed "catch-trials," two silhouettes were briefly presented on either side of fixation (matching the shape and/or predicted size of the search target), one of which was followed by a probe-stimulus. We found that participants were more accurate at reporting the location (Experiments 1 and 2) and orientation (Experiment 3) of probe stimuli when they were presented at the location of size-matching silhouettes. Thus, attentional templates incorporate the predicted size of an object based on the current viewing distance. This was only the case, however, when silhouettes also matched the shape of the search target (Experiment 2). We conclude that attentional templates for finding objects in scenes are shaped by a combination of category-specific attributes (shape) and context-dependent expectations about the likely appearance (size) of these objects at the current viewing location. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

The architecture of working memory: Features from multiple remembered objects produce parallel, coactive guidance of attention in visual search

Theories of working memory (WM) differ in their claims about the number of items that can be maintained in a state that directly interacts with other, ongoing cognitive operations (termed the focus of attention). A similar debate has arisen in the literature on visual working memory (VWM), focused on the number of items that can simultaneously interact with attentional priority. In 3 experiments, we used a redundancy-gain paradigm to provide a comprehensive test of the latter question. Participants searched for 2 cued features (e.g., a color and a shape) within a search array. The cued feature values changed on a trial-by-trial basis, requiring VWM. The target (when present) could match 1 of the cued features (single-target trials) or both cued features (redundant-target trials). We tested whether response time distributions contained a substantial proportion of trials with redundant-target responses that were faster than predicted by 2 independent guidance processes operating in parallel (i.e., violations of the race-model inequality). Violations are consistent with a coactive architecture in which both cued values guide attention in parallel and sum on the priority map. Robust violations were observed in all cases predicted by the hypothesis that multiple items in VWM can guide attention simultaneously, and these results were inconsistent with the hypothesis that guidance is limited to a single item simultaneously. When considered in the larger context of the literature on VWM and attention, the present results are consistent with a model of WM architecture in which the focus of attention can maintain multiple, independent representations. (PsycInfo Database Record (c) 2020 APA, all rights reserved).