Titre
The neural structures expressing perceptual hysteresis in visual letter recognition.
Type
article
Institution
Externe
Périodique
Auteur(s)
Kleinschmidt, A.
Auteure/Auteur
Büchel, C.
Auteure/Auteur
Hutton, C.
Auteure/Auteur
Friston, K.J.
Auteure/Auteur
Frackowiak, R.S.
Auteure/Auteur
Liens vers les personnes
ISSN
0896-6273
Statut éditorial
Publié
Date de publication
2002
Volume
34
Numéro
4
Première page
659
Dernière page/numéro d’article
666
Langue
anglais
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov'tPublication Status: ppublish
Résumé
Perception can change nonlinearly with stimulus contrast, and perceptual threshold may depend on the direction of contrast change. Such hysteresis effects in neurometric functions provide a signature of perceptual awareness. We recorded brain activity with functional neuroimaging in observers exposed to gradual contrast changes of initially hidden visual stimuli. Lateral occipital, frontal, and parietal regions all displayed both transient activations and hysteresis that correlated with change and maintenance of a percept, respectively. Medial temporal activity did not follow perception but increased during hysteresis and showed transient deactivations during perceptual transitions. These findings identify a set of brain regions sensitive to visual awareness and suggest that medial temporal structures may provide backward signals that account for neural and, thereby, perceptual hysteresis.
Sujets
PID Serval
serval:BIB_7E6CC979C776
PMID
Open Access
Oui
Date de création
2011-09-12T16:30:01.323Z
Date de création dans IRIS
2025-05-21T00:01:37Z