Interhemispheric transfer of visual motion information after a posterior callosal lesion: a neuropsychological and fMRI study.

Details

Serval ID
serval:BIB_B641D0744EA4
Type
Article: article from journal or magazin.
Publication sub-type
Case report (case report): feedback on an observation with a short commentary.
Collection
Publications
Institution
Title
Interhemispheric transfer of visual motion information after a posterior callosal lesion: a neuropsychological and fMRI study.
Journal
Experimental Brain Research. Experimentelle Hirnforschung. Expérimentation cérébrale
Author(s)
Clarke S., Maeder P., Meuli R., Staub F., Bellmann A., Regli L., de Tribolet N., Assal G.
ISSN
0014-4819
Publication state
Published
Issued date
2000
Peer-reviewed
Oui
Volume
132
Number
1
Pages
127-133
Language
english
Notes
Publication types: Case Reports ; Journal Article ; Research Support, Non-U.S. Gov't
Abstract
Interhemispheric transfer of visual information was investigated behaviourally and with functional magnetic resonance imaging (fMRI) 6 months after a lesion of the posterior two-thirds of the corpus callosum. On tachistoscopical left hemifield presentation, the patient was severely impaired in reading letters, words and geographical names and moderately impaired in naming pictures and colours. In contrast, interhemispheric transfer of visual motion information, tested by verbal report of the direction of short sequences of coherent dot motion presented within the left hemifield, was preserved. The pattern of cerebral activation elicited by apparent motion stimuli was studied with fMRI and compared to that of normal subjects. In normal subjects, apparent motion stimuli, as compared to darkness, activated strongly striate and extrastriate cortex. When presented to one hemifield only, the contralateral calcarine region was activated while regions on the occipital convexity, including putative area V5, were activated bilaterally. A similar activation pattern was found in the patient with a posterior callosal lesion; unilateral left or right hemifield stimulation was accompanied by activation in the contralateral and ipsilateral occipital convexity. Ipsilateral hemifield representation in the extrastriate visual cortex is believed to depend on callosal input. Our observation suggests that this is not the case for visual motion representation and that other, probably parallel, pathways may mediate visual motion transfer after posterior callosotomy.
Keywords
Adult, Brain, Cerebral Hemorrhage, Corpus Callosum, Darkness, Humans, Magnetic Resonance Imaging, Motion Perception, Names, Neuropsychological Tests, Photic Stimulation, Reading, Reference Values
Pubmed
Web of science
Create date
11/04/2008 8:23
Last modification date
20/08/2019 15:24
Usage data