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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.


Intact handles only. (A) Mean patient accuracies and (B) number of correct responses for two-item trials when only one item of an object pair was reported (either on the ipsilesional or on the contralesional side) as function of object pair condition when both handles were intact. Error bars denote SE.
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Figure 3: Intact handles only. (A) Mean patient accuracies and (B) number of correct responses for two-item trials when only one item of an object pair was reported (either on the ipsilesional or on the contralesional side) as function of object pair condition when both handles were intact. Error bars denote SE.

Mentions: To investigate whether the type of object pair affected identification performance when both handles were intact, the data from action-related (object-tool) pairs were compared with unrelated tool-tool and with unrelated object-object pairs. Figure 3A shows the mean performance for each object pair condition. The main effect of condition, F(1.9, 30.3) = 65.64, p < 0.001, = 0.804, reached significance. Bonferroni corrected multiple comparisons showed that accuracy was significantly higher for action-related objects and for unrelated tools than for unrelated object pairs (both p < 0.001), whereas there was no difference between the report of action-related objects and unrelated tool pairs. The benefit for the related (object-tool) pair condition over the unrelated object-object pair condition indicates that the presence of the tool (in the action-related object-tool condition) benefitted report of the other (non-tool) object, and that action relatedness can benefit report (cf. Riddoch et al., 2003). There was also a benefit for two tools compared with two objects, indicating a general advantage for reporting tools. There was a significant main effect of patient, F(7,16) = 5.19, p = 0.003, = 0.694. The interaction between condition and patient, F(13.3,30.3) = 9.00, p < 0.001, = 0.797 (see Figure 3A), was reliable. This indicates that the magnitude of the effect of condition varied across individuals, but all patients showed the effect.


Effects of broken affordance on visual extinction.

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

Intact handles only. (A) Mean patient accuracies and (B) number of correct responses for two-item trials when only one item of an object pair was reported (either on the ipsilesional or on the contralesional side) as function of object pair condition when both handles were intact. Error bars denote SE.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4585295&req=5

Figure 3: Intact handles only. (A) Mean patient accuracies and (B) number of correct responses for two-item trials when only one item of an object pair was reported (either on the ipsilesional or on the contralesional side) as function of object pair condition when both handles were intact. Error bars denote SE.
Mentions: To investigate whether the type of object pair affected identification performance when both handles were intact, the data from action-related (object-tool) pairs were compared with unrelated tool-tool and with unrelated object-object pairs. Figure 3A shows the mean performance for each object pair condition. The main effect of condition, F(1.9, 30.3) = 65.64, p < 0.001, = 0.804, reached significance. Bonferroni corrected multiple comparisons showed that accuracy was significantly higher for action-related objects and for unrelated tools than for unrelated object pairs (both p < 0.001), whereas there was no difference between the report of action-related objects and unrelated tool pairs. The benefit for the related (object-tool) pair condition over the unrelated object-object pair condition indicates that the presence of the tool (in the action-related object-tool condition) benefitted report of the other (non-tool) object, and that action relatedness can benefit report (cf. Riddoch et al., 2003). There was also a benefit for two tools compared with two objects, indicating a general advantage for reporting tools. There was a significant main effect of patient, F(7,16) = 5.19, p = 0.003, = 0.694. The interaction between condition and patient, F(13.3,30.3) = 9.00, p < 0.001, = 0.797 (see Figure 3A), was reliable. This indicates that the magnitude of the effect of condition varied across individuals, but all patients showed the effect.

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.