Preserved striate cortex is not sufficient to support the McCollough effect: evidence from two patients with cerebral achromatopsia.

Détails

ID Serval
serval:BIB_6F3E3DC583C5
Type
Article: article d'un périodique ou d'un magazine.
Sous-type
Etude de cas (case report): rapporte une observation et la commente brièvement.
Collection
Publications
Titre
Preserved striate cortex is not sufficient to support the McCollough effect: evidence from two patients with cerebral achromatopsia.
Périodique
Perception
Auteur(s)
Mullin C.R., Démonet J.F., Kentridge R.W., Heywood C.A., Goodale M.A., Steeves J.K.
ISSN
0301-0066 (Print)
ISSN-L
0301-0066
Statut éditorial
Publié
Date de publication
2009
Peer-reviewed
Oui
Volume
38
Numéro
12
Pages
1741-1748
Langue
anglais
Notes
Publication types: Case Reports ; Journal Article ; Research Support, Non-U.S. Gov't Publication Status: ppublish
Résumé
The McCollough effect (ME) is a colour aftereffect contingent on pattern orientation. This effect is generally thought to be mediated by primary visual cortex (V1) although this has remained the subject of some debate. To determine whether V1 is in fact sufficient to subserve the ME, we compared McCollough adaptation in controls to adaptation in two patients with damage to ventrotemporal cortex, resulting in achromatopsia, but who have spared V1. Each of these patients has some residual colour abilities of which he is unaware. Participants performed a 2AFC orientation-discrimination task for pairs of oblique and vertical/horizontal gratings both before and after adaptation to red/green oblique induction gratings. Successful ME induction would manifest itself as an improvement in oblique-orientation discrimination owing to the additional colour cue after adaptation. Indeed, in controls oblique grating discrimination improved post-adaptation. Further, a subdivision of our control group demonstrated successful ME induction despite a lack of conscious awareness of the added colour cue, indicating that conscious colour awareness is not required for ME induction. The patients, however, did not show improvement in oblique-orientation discrimination, indicating a lack of ME induction. This suggests that V1 must be connected to higher cortical colour areas to drive ME induction.
Mots-clé
Adult, Brain Injuries/physiopathology, Case-Control Studies, Color Perception/physiology, Color Perception Tests/methods, Color Vision Defects/physiopathology, Female, Figural Aftereffect/physiology, Humans, Male, Visual Cortex/physiopathology, Young Adult
Pubmed
Web of science
Création de la notice
24/03/2013 20:08
Dernière modification de la notice
20/08/2019 15:28
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