Do perceptual biases emerge early or late in visual processing? Decision-biases in motion perception

Visual perception is strongly influenced by contextual information. A good example is reference repulsion, where subjective reports about the direction of motion of a stimulus are significantly biased by the presence of an explicit reference. These perceptual biases could arise early, during sensory...

Full description

Bibliographic Details
Main Authors: Zamboni, Elisa, Ledgeway, Timothy, McGraw, Paul V., Schluppeck, Denis
Format: Article
Published: Royal Society 2016
Online Access:https://eprints.nottingham.ac.uk/33492/
_version_ 1848794643039256576
author Zamboni, Elisa
Ledgeway, Timothy
McGraw, Paul V.
Schluppeck, Denis
author_facet Zamboni, Elisa
Ledgeway, Timothy
McGraw, Paul V.
Schluppeck, Denis
author_sort Zamboni, Elisa
building Nottingham Research Data Repository
collection Online Access
description Visual perception is strongly influenced by contextual information. A good example is reference repulsion, where subjective reports about the direction of motion of a stimulus are significantly biased by the presence of an explicit reference. These perceptual biases could arise early, during sensory encoding, or alternatively they may reflect decision-related processes occurring relatively late in the task sequence. To separate these two competing possibilities, we asked (human) subjects to perform a fine motion-discrimination task and then estimate the direction of motion in the presence or absence of an oriented reference line. When subjects performed the discrimination task with the reference, but subsequently estimated motion direction in its absence, direction estimates were unbiased. However, when subjects viewed the same stimuli but performed the estimation task only, with the orientation of the reference line jittered on every trial, the directions estimated by subjects were biased and yoked to the orientation of the shifted reference line. These results show that judgments made relative to a reference are subject to late, decision-related biases. A model in which information about motion is integrated with that of an explicit reference cue, resulting in a late, decision-related re-weighting of the sensory representation, can account for these results.
first_indexed 2025-11-14T19:19:27Z
format Article
id nottingham-33492
institution University of Nottingham Malaysia Campus
institution_category Local University
last_indexed 2025-11-14T19:19:27Z
publishDate 2016
publisher Royal Society
recordtype eprints
repository_type Digital Repository
spelling nottingham-334922020-05-04T17:55:41Z https://eprints.nottingham.ac.uk/33492/ Do perceptual biases emerge early or late in visual processing? Decision-biases in motion perception Zamboni, Elisa Ledgeway, Timothy McGraw, Paul V. Schluppeck, Denis Visual perception is strongly influenced by contextual information. A good example is reference repulsion, where subjective reports about the direction of motion of a stimulus are significantly biased by the presence of an explicit reference. These perceptual biases could arise early, during sensory encoding, or alternatively they may reflect decision-related processes occurring relatively late in the task sequence. To separate these two competing possibilities, we asked (human) subjects to perform a fine motion-discrimination task and then estimate the direction of motion in the presence or absence of an oriented reference line. When subjects performed the discrimination task with the reference, but subsequently estimated motion direction in its absence, direction estimates were unbiased. However, when subjects viewed the same stimuli but performed the estimation task only, with the orientation of the reference line jittered on every trial, the directions estimated by subjects were biased and yoked to the orientation of the shifted reference line. These results show that judgments made relative to a reference are subject to late, decision-related biases. A model in which information about motion is integrated with that of an explicit reference cue, resulting in a late, decision-related re-weighting of the sensory representation, can account for these results. Royal Society 2016-06-22 Article PeerReviewed Zamboni, Elisa, Ledgeway, Timothy, McGraw, Paul V. and Schluppeck, Denis (2016) Do perceptual biases emerge early or late in visual processing? Decision-biases in motion perception. Proceedings of the Royal Society B: Biological Sciences, 283 (1833). p. 20160263. ISSN 1471-2954 http://rspb.royalsocietypublishing.org/content/283/1833/20160263 doi:10.1098/rspb.2016.0263 doi:10.1098/rspb.2016.0263
spellingShingle Zamboni, Elisa
Ledgeway, Timothy
McGraw, Paul V.
Schluppeck, Denis
Do perceptual biases emerge early or late in visual processing? Decision-biases in motion perception
title Do perceptual biases emerge early or late in visual processing? Decision-biases in motion perception
title_full Do perceptual biases emerge early or late in visual processing? Decision-biases in motion perception
title_fullStr Do perceptual biases emerge early or late in visual processing? Decision-biases in motion perception
title_full_unstemmed Do perceptual biases emerge early or late in visual processing? Decision-biases in motion perception
title_short Do perceptual biases emerge early or late in visual processing? Decision-biases in motion perception
title_sort do perceptual biases emerge early or late in visual processing? decision-biases in motion perception
url https://eprints.nottingham.ac.uk/33492/
https://eprints.nottingham.ac.uk/33492/
https://eprints.nottingham.ac.uk/33492/