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Effects of broken affordance on visual extinction.

Wulff M, Humphreys GW - Front Hum Neurosci (2015)

Bottom Line: In line with previous research (e.g., Riddoch et al., 2006), extinction was reduced when action-related object pairs and when unrelated tool pairs were presented compared to unrelated object pairs.In addition, performance with action-related objects decreased when the tool appeared on the ipsilesional side compared to when it was on the contralesional side, but only when the tool handle was intact.This attentional capture effect is mediated by the affordance to the intact tool.

View Article: PubMed Central - PubMed

Affiliation: School of Psychology, University of Birmingham Birmingham, UK.

ABSTRACT
Previous studies have shown that visual extinction can be reduced if two objects are positioned to "afford" an action. Here we tested if this affordance effect was disrupted by "breaking" the affordance, i.e., if one of the objects actively used in the action had a broken handle. We assessed the effects of broken affordance on recovery from extinction in eight patients with right hemisphere lesions and left-sided extinction. Patients viewed object pairs that were or were not commonly used together and that were positioned for left- or right-hand actions. In the unrelated pair conditions, either two tools or two objects were presented. In line with previous research (e.g., Riddoch et al., 2006), extinction was reduced when action-related object pairs and when unrelated tool pairs were presented compared to unrelated object pairs. There was no significant difference in recovery rate between action-related (object-tool) and unrelated tool pairs. In addition, performance with action-related objects decreased when the tool appeared on the ipsilesional side compared to when it was on the contralesional side, but only when the tool handle was intact. There were minimal effects of breaking the handle of an object rather than a tool, and there was no effect of breaking the handle on either tools or objects on single item trials. The data suggest that breaking the handle of a tool lessens the degree to which it captures attention, with this attentional capture being strongest when the tool appears on the ipsilesional side. The capture of attention by the ipsilesional item then reduces the chance of detecting the contralesional stimulus. This attentional capture effect is mediated by the affordance to the intact tool.

No MeSH data available.


Action-related objects vs. unrelated objects, with a broken object handle. (A) Mean accuracy of performance for action-related and unrelated object pairs as function of whether the broken object handle was on the contralesional or on the ipsilesional side. (B) Mean patient accuracies as function of condition (B) and side of broken object (C) with error bars indicating SE. Asterisks denote significance (**p < 0.01).
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Figure 7: Action-related objects vs. unrelated objects, with a broken object handle. (A) Mean accuracy of performance for action-related and unrelated object pairs as function of whether the broken object handle was on the contralesional or on the ipsilesional side. (B) Mean patient accuracies as function of condition (B) and side of broken object (C) with error bars indicating SE. Asterisks denote significance (**p < 0.01).

Mentions: The within-subject factors were condition (action-related objects vs. unrelated objects) and location of the broken object (contralesional vs. ipsilesional). Patient was treated as a between-subject factor. The main effects of condition, F(1,16) = 133.36, p < 0.001, = 0.893 (action-related objects > unrelated objects), side of broken object, F(1,16) = 9.22, p = 0.008, = 0.365 (ipsilesional > contralesional stimuli), and patient, F(7,16) = 3.77, p = 0.013, = 0.623, were reliable. There was a significant interaction between condition and side of broken object, F(1,16) = 12.46, p = 0.003, = 0.438 (Figure 7A). In the action-related condition, performance was increased when the broken object was on the ipsilesional side and the intact tool was on the contralesional side compared to when the stimuli were in the opposite positions, t(23) = 3.14, p = 0.005. In contrast, there was no reliable effect of the side of the broken object with unrelated object pairs. There were also interactions between condition and patient, F(7,16) = 7.57, p < 0.001, = 0.768 (Figure 7B), and side of broken object and patient, F(7,16) = 2.63, p = 0.051, = 0.535 (Figure 7C). There was an overall advantage for action-related pairs over unrelated object pairs and for intact tools/broken object handles on the contralesional compared with the ipsilesional side, but these effects varied in size although in the same direction across patients.


Effects of broken affordance on visual extinction.

Wulff M, Humphreys GW - Front Hum Neurosci (2015)

Action-related objects vs. unrelated objects, with a broken object handle. (A) Mean accuracy of performance for action-related and unrelated object pairs as function of whether the broken object handle was on the contralesional or on the ipsilesional side. (B) Mean patient accuracies as function of condition (B) and side of broken object (C) with error bars indicating SE. Asterisks denote significance (**p < 0.01).
© Copyright Policy
Related In: Results  -  Collection

License
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getmorefigures.php?uid=PMC4585295&req=5

Figure 7: Action-related objects vs. unrelated objects, with a broken object handle. (A) Mean accuracy of performance for action-related and unrelated object pairs as function of whether the broken object handle was on the contralesional or on the ipsilesional side. (B) Mean patient accuracies as function of condition (B) and side of broken object (C) with error bars indicating SE. Asterisks denote significance (**p < 0.01).
Mentions: The within-subject factors were condition (action-related objects vs. unrelated objects) and location of the broken object (contralesional vs. ipsilesional). Patient was treated as a between-subject factor. The main effects of condition, F(1,16) = 133.36, p < 0.001, = 0.893 (action-related objects > unrelated objects), side of broken object, F(1,16) = 9.22, p = 0.008, = 0.365 (ipsilesional > contralesional stimuli), and patient, F(7,16) = 3.77, p = 0.013, = 0.623, were reliable. There was a significant interaction between condition and side of broken object, F(1,16) = 12.46, p = 0.003, = 0.438 (Figure 7A). In the action-related condition, performance was increased when the broken object was on the ipsilesional side and the intact tool was on the contralesional side compared to when the stimuli were in the opposite positions, t(23) = 3.14, p = 0.005. In contrast, there was no reliable effect of the side of the broken object with unrelated object pairs. There were also interactions between condition and patient, F(7,16) = 7.57, p < 0.001, = 0.768 (Figure 7B), and side of broken object and patient, F(7,16) = 2.63, p = 0.051, = 0.535 (Figure 7C). There was an overall advantage for action-related pairs over unrelated object pairs and for intact tools/broken object handles on the contralesional compared with the ipsilesional side, but these effects varied in size although in the same direction across patients.

Bottom Line: In line with previous research (e.g., Riddoch et al., 2006), extinction was reduced when action-related object pairs and when unrelated tool pairs were presented compared to unrelated object pairs.In addition, performance with action-related objects decreased when the tool appeared on the ipsilesional side compared to when it was on the contralesional side, but only when the tool handle was intact.This attentional capture effect is mediated by the affordance to the intact tool.

View Article: PubMed Central - PubMed

Affiliation: School of Psychology, University of Birmingham Birmingham, UK.

ABSTRACT
Previous studies have shown that visual extinction can be reduced if two objects are positioned to "afford" an action. Here we tested if this affordance effect was disrupted by "breaking" the affordance, i.e., if one of the objects actively used in the action had a broken handle. We assessed the effects of broken affordance on recovery from extinction in eight patients with right hemisphere lesions and left-sided extinction. Patients viewed object pairs that were or were not commonly used together and that were positioned for left- or right-hand actions. In the unrelated pair conditions, either two tools or two objects were presented. In line with previous research (e.g., Riddoch et al., 2006), extinction was reduced when action-related object pairs and when unrelated tool pairs were presented compared to unrelated object pairs. There was no significant difference in recovery rate between action-related (object-tool) and unrelated tool pairs. In addition, performance with action-related objects decreased when the tool appeared on the ipsilesional side compared to when it was on the contralesional side, but only when the tool handle was intact. There were minimal effects of breaking the handle of an object rather than a tool, and there was no effect of breaking the handle on either tools or objects on single item trials. The data suggest that breaking the handle of a tool lessens the degree to which it captures attention, with this attentional capture being strongest when the tool appears on the ipsilesional side. The capture of attention by the ipsilesional item then reduces the chance of detecting the contralesional stimulus. This attentional capture effect is mediated by the affordance to the intact tool.

No MeSH data available.