Titre
Preserved striate cortex is not sufficient to support the McCollough effect: evidence from two patients with cerebral achromatopsia.
Type
étude de cas
Institution
Externe
Périodique
Auteur(s)
Mullin, C.R.
Auteure/Auteur
Démonet, J.F.
Auteure/Auteur
Kentridge, R.W.
Auteure/Auteur
Heywood, C.A.
Auteure/Auteur
Goodale, M.A.
Auteure/Auteur
Steeves, J.K.
Auteure/Auteur
Liens vers les personnes
ISSN
0301-0066
Statut éditorial
Publié
Date de publication
2009
Volume
38
Numéro
12
Première page
1741
Dernière page/numéro d’article
1748
Peer-reviewed
Oui
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.
PID Serval
serval:BIB_6F3E3DC583C5
PMID
Date de création
2013-03-24T18:08:45.967Z
Date de création dans IRIS
2025-05-21T03:36:44Z