The Role of the Parietal Lobe in Visual Extinction Studied with Transcranial Magnetic Stimulation

Autor/inn/en	Battelli, Lorella; Alvarez, George A.; Carlson, Thomas; Pascual-Leone, Alvaro
Titel	The Role of the Parietal Lobe in Visual Extinction Studied with Transcranial Magnetic Stimulation
Quelle	In: Journal of Cognitive Neuroscience, 21 (2009) 10, S.1946-1955 (10 Seiten) PDF als Volltext Verfügbarkeit
Sprache	englisch
Dokumenttyp	gedruckt; online; Zeitschriftenaufsatz
ISSN	0898-929X
DOI	10.1162/jocn.2008.21149
Schlagwörter	Stimulation; Inhibition; Visual Perception; Brain; Cognitive Processes; Vision; Brain Hemisphere Functions; Motion; Eye Movements; Spatial Ability; Diagnostic Tests; Patients; Neurological Impairments + Suchen Sie Ihr Suchwort? Hemmung; Visuelle Wahrnehmung; Gehirn; Cognitive process; Kognitiver Prozess; Bewegungsablauf; Augenbewegung; Räumliches Vorstellungsvermögen; Diagnostic test; Diagnostischer Test; Patient; Neurodegenerative Erkrankung
Abstract	Interhemispheric competition between homologous areas in the human brain is believed to be involved in a wide variety of human behaviors from motor activity to visual perception and particularly attention. For example, patients with lesions in the posterior parietal cortex are unable to selectively track objects in the contralesional side of visual space when targets are simultaneously present in the ipsilesional visual field, a form of visual extinction. Visual extinction may arise due to an imbalance in the normal interhemispheric competition. To directly assess the issue of reciprocal inhibition, we used fMRI to localize those brain regions active during attention-based visual tracking and then applied low-frequency repetitive transcranial magnetic stimulation over identified areas in the left and right intraparietal sulcus to asses the behavioral effects on visual tracking. We induced a severe impairment in visual tracking that was selective for conditions of simultaneous tracking in both visual fields. Our data show that the parietal lobe is essential for visual tracking and that the two hemispheres compete for attentional resources during tracking. Our results provide a neuronal basis for visual extinction in patients with parietal lobe damage. (As Provided).
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Erfasst von	ERIC (Education Resources Information Center), Washington, DC
Update	2017/4/10