2.50
Hdl Handle:
http://hdl.handle.net/2436/12203
Title:
Can subthreshold summation be observed with the Ehrenstein illusion?
Authors:
Salvano-Pardieu, Veronique; Taliercio, Alain; Manktelow, Ken I.; Meigen, Thomas; Wink, Brian
Abstract:
Subthreshold summation between physical target lines and illusory contours induced by edges such as those produced in the Kanizsa illusion has been reported in previous studies. Here, we investigated the ability of line-induced illusory contours, using Ehrenstein figures, to produce similar subthreshold summation. In the first experiment, three stimulus conditions were presented. The target line was superimposed on the illusory contour of a four-arm Ehrenstein figure, or the target was presented between two dots (which replaced the arms of the Ehrenstein figure), or the target was presented on an otherwise blank screen (control). Detection of the target line was significantly worse when presented on the illusory contour (on the Ehrenstein figure) than when presented between two dots. This result was consistent for both curved and straight target lines, as well as for a 100 ms presentation duration and unlimited presentation duration. Performance was worst in the control condition. The results for the three stimulus conditions were replicated in a second experiment in which an eight-arm Ehrenstein figure was used to produce a stronger and less ambiguous illusory contour. In the third experiment, the target was either superimposed on the illusory contour, or was located across the central gap (illusory surface) of the Ehrenstein figure, collinear with two arms of the figure. As in the first two experiments, the target was either presented on the Ehrenstein figure, or between dots, or on a blank screen. Detection was better in the dot condition than in the Ehrenstein condition, regardless of whether the target was presented on the illusory contour or collinear with the arms of the Ehrenstein figure. These three experiments demonstrate the ability of reduced spatial uncertainty to facilitate the detection of a target line, but do not provide any evidence for subthreshold summation between a physical target line and the illusory contours produced by an Ehrenstein figure. The incongruence of these results with previous findings on Kanizsa figures is discussed.
Citation:
Perception, 35(7): 965–981
Publisher:
Pion
Issue Date:
2006
URI:
http://hdl.handle.net/2436/12203
DOI:
10.1068/p5187
Additional Links:
http://www.perceptionweb.com/abstract.cgi?id=p5187
Submitted date:
2007-05-31
Type:
Article
Language:
en
ISSN:
03010066; 14684233
Appears in Collections:
Psychology of Health Research Group

Full metadata record

DC FieldValue Language
dc.contributor.authorSalvano-Pardieu, Veronique-
dc.contributor.authorTaliercio, Alain-
dc.contributor.authorManktelow, Ken I.-
dc.contributor.authorMeigen, Thomas-
dc.contributor.authorWink, Brian-
dc.date.accessioned2007-05-31T14:11:27Z-
dc.date.available2007-05-31T14:11:27Z-
dc.date.issued2006-
dc.date.submitted2007-05-31-
dc.identifier.citationPerception, 35(7): 965–981en
dc.identifier.issn03010066-
dc.identifier.issn14684233-
dc.identifier.doi10.1068/p5187-
dc.identifier.urihttp://hdl.handle.net/2436/12203-
dc.description.abstractSubthreshold summation between physical target lines and illusory contours induced by edges such as those produced in the Kanizsa illusion has been reported in previous studies. Here, we investigated the ability of line-induced illusory contours, using Ehrenstein figures, to produce similar subthreshold summation. In the first experiment, three stimulus conditions were presented. The target line was superimposed on the illusory contour of a four-arm Ehrenstein figure, or the target was presented between two dots (which replaced the arms of the Ehrenstein figure), or the target was presented on an otherwise blank screen (control). Detection of the target line was significantly worse when presented on the illusory contour (on the Ehrenstein figure) than when presented between two dots. This result was consistent for both curved and straight target lines, as well as for a 100 ms presentation duration and unlimited presentation duration. Performance was worst in the control condition. The results for the three stimulus conditions were replicated in a second experiment in which an eight-arm Ehrenstein figure was used to produce a stronger and less ambiguous illusory contour. In the third experiment, the target was either superimposed on the illusory contour, or was located across the central gap (illusory surface) of the Ehrenstein figure, collinear with two arms of the figure. As in the first two experiments, the target was either presented on the Ehrenstein figure, or between dots, or on a blank screen. Detection was better in the dot condition than in the Ehrenstein condition, regardless of whether the target was presented on the illusory contour or collinear with the arms of the Ehrenstein figure. These three experiments demonstrate the ability of reduced spatial uncertainty to facilitate the detection of a target line, but do not provide any evidence for subthreshold summation between a physical target line and the illusory contours produced by an Ehrenstein figure. The incongruence of these results with previous findings on Kanizsa figures is discussed.en
dc.format.extent366474 bytes-
dc.format.mimetypeapplication/pdf-
dc.language.isoenen
dc.publisherPionen
dc.relation.urlhttp://www.perceptionweb.com/abstract.cgi?id=p5187en
dc.subjectEhrenstein illusionen
dc.subjectEhrenstein figuresen
dc.subjectSubthreshold summationen
dc.subjectPerception-
dc.titleCan subthreshold summation be observed with the Ehrenstein illusion?en
dc.typeArticleen
dc.format.digYES-
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