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Titolo:
Shifting visual attention in space: an electrophysiological analysis usinghigh spatial resolution mapping
Autore:
Hopf, JM; Mangun, GR;
Indirizzi:
Otto von Guericke Univ, Dept Neurol 2, D-39120 Magdeburg, Germany Otto vonGuericke Univ Magdeburg Germany D-39120 9120 Magdeburg, Germany Duke Univ, Ctr Cognit Neurosci, Durham, NC 27708 USA Duke Univ Durham NC USA 27708 , Ctr Cognit Neurosci, Durham, NC 27708 USA
Titolo Testata:
CLINICAL NEUROPHYSIOLOGY
fascicolo: 7, volume: 111, anno: 2000,
pagine: 1241 - 1257
SICI:
1388-2457(200007)111:7<1241:SVAISA>2.0.ZU;2-8
Fonte:
ISI
Lingua:
ENG
Soggetto:
POSTERIOR PARIETAL CORTEX; POSITRON EMISSION TOMOGRAPHY; SELECTIVE ATTENTION; VISUOSPATIAL ATTENTION; DIRECTED ATTENTION; BRAIN POTENTIALS; COVERT ATTENTION; HEMISPHERIC ASYMMETRIES; SUSTAINED ATTENTION; CORTICAL AREAS;
Keywords:
event-related potential; shifting visual attention; spatial; attentional control;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
98
Recensione:
Indirizzi per estratti:
Indirizzo: Hopf, JM Otto von Guericke Univ, Dept Neurol 2, Leipziger Str 44, D-39120 Magdeburg, Germany Otto von Guericke Univ Leipziger Str 44 Magdeburg Germany D-39120
Citazione:
J.M. Hopf e G.R. Mangun, "Shifting visual attention in space: an electrophysiological analysis usinghigh spatial resolution mapping", CLIN NEU, 111(7), 2000, pp. 1241-1257

Abstract

Objectives: Evidence from cortical electrophysiology and functional imaging converges on the view that visual spatial selective attention results in a facilitation of early sensory processing in visual cortical structures. Little is known, however, about the neural control processes that lead to this facilitation. The present study was aimed at further investigating thesecontrol processes and their neural correlates by analyzing high spatial resolution maps of brain activity that were evoked by attention-directing cues, but occurred prior to presentation of the target stimulus. Methods: Subjects (n = 14) were presented with central arrow cues that instructed them to attend covertly to either a left or right field location inorder to compare two subsequent target stimuli simultaneously presented tothe location. On half of the trials, targets were presented to the cued location, while in the other half, targets were presented to the opposite visual field location. Subjects had to respond via button press on 16% of the trials when target stimuli were identical. Event-related potentials (ERPs) were recorded from 92 scalp electrodes which allowed a sufficiently finegrained analysis of the regional specificity of the ERP components. Results: In response to the cues, an initial component over occipital-parietal electrode sites was consistent with an early involvement of the posterior-parietal cortex, perhaps in the initial step of attentional orienting. A second component over the lateral-prefrontal cortex is consistent with the voluntary control and maintenance of attention, a function known to be subserved by frontal cortical structures. A late component narrowly focussed over occipital-temporal electrode sites is most plausibly related to activation of parts of the ventral extrastriate cortex. Conclusions: The data support the current view that voluntarily orienting visual attention in space leads to top-down modulations in cortical excitability of ventral extrastriate regions initiated by posterior-parietal and mediated by lateral-prefrontal cortical structures. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.

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Documento generato il 25/01/20 alle ore 06:28:52