Involuntary attentional capture by task-irrelevant objects that match the search template for category detection in natural scenes

Abstract

Theories of visual search postulate that the selection of targets amongst distractors involves matching visual input to a top-down attentional template. Previous work has provided evidence that feature-based attentional templates affect visual processing globally across the visual field. In the present study, we asked whether more naturalistic, categorylevel attentional templates also modulate visual processing in a spatially global and obligatory way. Subjects were cued to detect people or cars in a diverse set of photographs of realworld scenes. On a subset of trials, silhouettes of people and cars appeared in search-irrelevant locations that subjects were instructed to ignore, and subjects were required to respond to the location of a subsequent dot probe. In three experiments, results showed a consistency effect on dot-probe trials: dot probes were detected faster when they appeared in the location of the cued category compared with the non-cued category, indicating attentional capture by template-matching stimuli. Experiments 1 and 2 showed that this capture was involuntary: consistency effects persisted under conditions in which attending to silhouettes of the cued category was detrimental to performance. Experiment 3 tested whether these effects could be attributed to non-attentional effects related to the processing of the category cues. Results showed a consistency effect when subjects searched for category exemplars but not when they searched for objects semantically related to the cued category. Together, these results indicate that attentional templates for familiar object categories affect visual processing across the visual field, leading to involuntary attentional capture by template-matching stimuli.

Neural Correlates of Divided Attention in Natural Scenes

“…Contingent attention capture was only observed for category exemplars (silhouettes of the object) or characteristic parts of the object (such as the wheels of a car or limbs of a person) but not for objects semantically related to the cued category (e.g., air freshener, car radio, bracelets, hats). These findings suggest that attentional capture in naturalistic scenes is contingent on a search template composed of visual features characterizing the target (Reeder, van Zoest, & Peelen, 2015;Evans & Treisman, 2005). Several studies have suggested that different neural structures are responsible for target and distractor processing, namely, in frontal and parietal areas, respectively.…”

Preparatory attention in visual cortex

“…These representations may be located in areas beyond the EVC yet still show coarse retinotopic specificity . A currently debated topic is whether preparatory attention can also be directed to conceptual‐level representations, such as superordinate categories like furniture or food . In the current framework, this would be possible as long as there is a set of mid‐ or high‐level shape (or texture, or color) features that characterize the category.…”

“…[106][107][108][109] A currently debated topic is whether preparatory attention can also be directed to conceptual-level representations, such as superordinate categories like furniture or food. [110][111][112][113][114][115][116] In the current framework, this would be possible as long as there is a set of mid-or high-level shape (or texture, or color) features that characterize the category. For abstract categories that lack such characterizing visual features altogether, preparatory attention in the visual cortex is unlikely to be an efficient mechanism of attentional guidance.…”

Spatial attention follows category-based attention during naturalistic visual search: evidence from MEG decoding

“…The spatial modulation observed here provides a neural correlate of behavioral findings of attentional capture by objects matching a top-down category-based attentional set (Reeder and Peelen, 2013; Reeder et al, 2015). In these studies, participants searched for cars and people in natural scenes.…”

“…These tasks require spatial attention to bind features, as elegantly shown by work in neurological patients with parietal damage (Cohen and Rafal, 1991; Friedman-Hill et al, 1995). Thus, while not directly required in the current task, spatial selection may be an integral and obligatory aspect of top-down attention, even when directed to high-level categories (Wyble et al, 2013; Reeder et al, 2015).…”