Local and global factors of similarity in visual search

Grünau, Michael von; Dubé, Stéphane; Galera, Cesar

doi:10.3758/bf03205314

Cited by 18 publications

(6 citation statements)

References 39 publications

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“…This suggests that the feature binding requirement of the FC task increased the attentional load of the task over and above any increase induced by greater task difficulty. Findings from the human cognitive literature support this proposition: even after controlling for target-distractor similarity, which makes both FS and FC tasks more attentionally demanding, feature binding in itself requires additional attentional resources over and above those needed for making fine perceptual discriminations (Carter, 1982;Duncan and Humphreys, 1989;von Grünau et al, 1994;Foldi et al, 2005).…”

Section: Discussionsupporting

confidence: 48%

Cholinergic Deafferentation of the Neocortex Using 192 IgG-Saporin Impairs Feature Binding In Rats

Botly¹,

Rosa²

2009

J. Neurosci.

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The binding problem refers to the fundamental challenge of the CNS to integrate sensory information registered by distinct brain regions to form a unified neural representation of a stimulus. Although the human cognitive literature has established that attentional processes in frontoparietal cortices support feature binding, the neurochemical and specific downstream neuroanatomical contributions to feature binding remain unknown. Using systemic pharmacology in rats, it has been shown that the neuromodulator acetylcholine is essential for feature binding at encoding, but the neural source of such critical cholinergic neurotransmission has yet to be identified. Cholinergic efferents from the nucleus basalis magnocellularis (NBM) of the basal forebrain provide the majority of the cholinergic input to the neocortex. Accordingly, it was hypothesized that the NBM is the neural source that provides the critical neuromodulatory support for feature binding. To test this hypothesis, rats received bilateral 192 IgG-saporin lesions of the NBM, and their feature binding performance was tested using a forced-choice digging paradigm. Relative to sham-lesioned rats, NBM-lesioned rats were significantly impaired at acquiring a crossmodal feature conjunction (FC) stimulus set that required feature binding, whereas their ability to retrieve an FC stimulus set and to acquire two crossmodal feature singleton stimulus sets, one of greater difficulty than the other but neither requiring feature binding, remained intact. These behavioral findings, along with histological analyses demonstrating positive relationships between feature-binding acquisition and markers of cholinergic activity in frontoparietal regions, reveal the importance of neocortical cholinergic input from the NBM to feature binding at encoding.

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Section: Discussionsupporting

confidence: 48%

Cholinergic Deafferentation of the Neocortex Using 192 IgG-Saporin Impairs Feature Binding In Rats

Botly¹,

Rosa²

2009

J. Neurosci.

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“…In both search (von Grünau, Dubé, & Galera, 1994) and nonsearch (Mason, 1982;Zegarra-Moran & Geiger, 1993) conditions, the perception of letters and figures has been compared, but to our knowledge, no clear dissociation between letters and shapes, as in the present experiments, has previously been obtained (although Huckauf et al, 1999, reported larger effects of lateral masking for nonletters than for letters). According to the integration strategies hypothesis, this is because these experiments fail to require their participants to distinguish between letters and shapes.…”

Section: Discussionmentioning

confidence: 60%

Negative and positive congruence effects in letters and shapes

Leeuwen

Lachmann

2004

Perception & Psychophysics

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In six experiments in which a binary classification task was used, letter and nonletter (geometrical shapes, pseudoletters, or rotated letters) targets were presented either in isolation or surrounded by a geometrical shape. The surrounding shape could be congruent or incongruent with the target. When the classification required a distinction between letters and nonletters, either explicitly (Experiments 1-3) or implicitly (Experiment 4), a negative congruence effect was obtained for letters, contrasting with a regular, positive congruence effect for nonletters. When no distinction was to be made, letters and nonletters invariably showed a positive congruence effect (Experiments 5 and 6). In particular, between Experiments 1-4 and Experiments 5 and 6, the occurrence of negative or positive congruence effects for the same stimuli depended on the task. Feature interaction, target selection, and response competition explanations were tested against a feature integration approach. The results are explained in terms of different feature integration strategies for letters and nonletters. CONGRUENCE IN LETTERS AND SHAPES909 sults of even these earliest studies cannot be understood fully on the basis of feature interaction alone. For instance, in Estes (1982), the effect of target-flanker similarity was minimal at an intermediate degree of similarity, a result Estes ascribed to the mediation of higher order processes. These processes are likely to involve task-specific factors.In particular, we may consider the role of task-specific factors in attentional target selection. Distractor information competes for selection when the perceiver is allocating attention to the target. This effect, too, will be stronger the more similar in shape the nontarget is to the target. When the stimulus is complex, the task is difficult, and distractors competing for attention may sometimes have to be suppressed while a target is selected. This provides another possible source of negative congruence effects. Accordingly, the time it takes to classify a target is longer if it is surrounded by nontargets of similar shape than if it is surrounded by ones of different shape (Bavelier, Deruelle, & Proksch, 2000;Briand, 1994;van Leeuwen & Bakker, 1995). These effects contrast with those usually obtained in more simple displays, where the time it takes to classify a target is shorter when congruent distractors surround it than when it is surrounded by incongruent ones. The latter, positive congruence effects have been studied extensively and are generally attributed to competition of late response-related processes (Eriksen & Eriksen, 1974). According to the literature, these effects are characteristic of simple stimuli, because when the task is easy (Lavie, 1995), attention recruited for feature integration (Treisman & Gelade, 1980) spills over to irrelevant stimulus attributes. When these call for a response opposite to that of the target, response competition will result.In sum, the effects of irrelevant surrounding information are commonly ex...

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“…Participants were asked to locate the target square in the stimulus array and to indicate the orientation of the line inside by key press. Target‐nontarget similarity was low when the nontargets were circles, but it was high when nontargets were diamonds, that is, squares rotated by 45° (Von Grünau, Dube, & Galera, ). In order to measure ERPs to the distractor, we used a set size of eight so that two elements could be placed on the vertical midline, above and below the fixation point (see Figure ).…”

Section: Methodsmentioning

confidence: 99%

Salient‐but‐irrelevant stimuli cause attentional capture in difficult, but attentional suppression in easy visual search

Barras

Kerzel

2017

Psychophysiology

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Search for a shape target is difficult when its shape is similar to the shape of the surrounding nontargets and easy when it is dissimilar. We asked whether interference from a salient but irrelevant color singleton depended on search difficulty as manipulated by target-nontarget similarity. We found that interference was strong in difficult searches, and the occurrence of an electrophysiological index of attentional selectivity (the N2pc component) confirmed that attention was captured by the distractor. In contrast, interference from the distractor was weak with easy searches, and the occurrence of the P component confirmed that saliency signals from the distractor were suppressed. The results suggest that attentional suppression of salient but irrelevant distractors is only possible when search is efficient (i.e., with low target-nontarget similarity), otherwise, attentional capture occurs. Further, we analyzed the Ppc component, a positivity occurring between 100 and 200 ms after stimulus onset contralateral to a salient feature discontinuity. It has been suggested that the Ppc reflects bottom-up saliency signals, but we found the Ppc to occur only when the salient stimulus was unlikely to be selected, as in efficient searches. Thus, attentional requirements modulate the Ppc component.

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Local and global factors of similarity in visual search

Cited by 18 publications

References 39 publications

Cholinergic Deafferentation of the Neocortex Using 192 IgG-Saporin Impairs Feature Binding In Rats

Cholinergic Deafferentation of the Neocortex Using 192 IgG-Saporin Impairs Feature Binding In Rats

Negative and positive congruence effects in letters and shapes

Salient‐but‐irrelevant stimuli cause attentional capture in difficult, but attentional suppression in easy visual search

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