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Title: Radial Bias Alters Perceived Object Orientation
Orientation sensitivity is a fundamental property of the visual system, but not all orientations are created equal. For instance, radially oriented stimuli, aligned with a line intersecting the center of gaze, produce greater activity throughout the visual cortex and are associated with greater perceptual sensitivity compared with other orientations. Here, we discuss a robust visual illusion that is likely related to this preference. Using a continuous response measure, participants ( N = 36 adults) indicated the gap position in a peripheral Landolt C placed in one of eight orientations and eight locations along four meridians (vertical, horizontal, 45°, 135°). The error distributions revealed that the perceived gap was attracted toward the radial axis. For instance, the gap in a regular C would often be wrongly perceived as tilted 45° corresponding to the oblique meridian where it was placed. These findings demonstrate an unsuspected early-vision influence on the perceived orientation of an object.  more » « less
Award ID(s):
2104666 1849169
PAR ID:
10375892
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
SAGE Publications
Date Published:
Journal Name:
Psychological Science
Volume:
33
Issue:
12
ISSN:
0956-7976
Format(s):
Medium: X Size: p. 2098-2108
Size(s):
p. 2098-2108
Sponsoring Org:
National Science Foundation
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