Anatomy and time course of discrimination and categorization processes in vision: an fMRI study.

Détails

ID Serval
serval:BIB_C3219945E47B
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Anatomy and time course of discrimination and categorization processes in vision: an fMRI study.
Périodique
Neuroimage
Auteur(s)
Pernet C., Franceries X., Basan S., Cassol E., Démonet J.F., Celsis P.
ISSN
1053-8119 (Print)
ISSN-L
1053-8119
Statut éditorial
Publié
Date de publication
2004
Peer-reviewed
Oui
Volume
22
Numéro
4
Pages
1563-1577
Langue
anglais
Notes
Publication types: Journal ArticlePublication Status: ppublish
Résumé
Studies investigating the cerebral areas involved in visual processes generally oppose either different tasks or different stimulus types. This work addresses, by fMRI, the interaction between the type of task (discrimination vs. categorization) and the type of stimulus (Latin letters, well-known geometrical figures, and Korean letters). Behavioral data revealed that the two tasks did not differ in term of percentage of errors or correct responses, but a delay of 185 ms was observed for the categorization task in comparison with the discrimination task. All conditions activated a common neural network that includes both striate and extrastriate areas, especially the fusiform gyri, the precunei, the insulae, and the dorsolateral frontal cortex. In addition, interaction analysis revealed that the right insula was sensitive to both tasks and stimuli, and that stimulus type induced several significant signal variations for the categorization task in right frontal cortex, the right middle occipital gyrus, the right cuneus, and the left and right fusiform gyri, whereas for the discrimination task, significant signal variations were observed in the right occipito-parietal junction only. Finally, analyzing the latency of the BOLD signal also revealed a differential neural dynamics according to tasks but not to stimulus type. These temporal differences suggest a parallel hemisphere processing in the discrimination task vs. a cooperative interhemisphere processing in the categorization task that may reflect the observed differences in reaction time.
Mots-clé
Adult, Attention/physiology, Brain Mapping, Cerebral Cortex/physiology, Discrimination Learning/physiology, Dominance, Cerebral/physiology, Female, Frontal Lobe/physiology, Humans, Image Enhancement, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Male, Oxygen/blood, Pattern Recognition, Visual/physiology, Problem Solving/physiology, Reading
Pubmed
Web of science
Création de la notice
24/03/2013 19:41
Dernière modification de la notice
03/03/2018 21:11
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