Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Paradigm-dependent modulation of event-related fMRI activity evoked by theoddball task
Autore:
Clark, VP; Fannon, S; Lai, S; Benson, R;
Indirizzi:
Univ Connecticut, Ctr Hlth, Dept Psychiat, Farmington, CT 06030 USA Univ Connecticut Farmington CT USA 06030 ychiat, Farmington, CT 06030 USA Univ Connecticut, Ctr Hlth, Dept Diagnost Imaging & Therapeut, Farmington,CT 06030 USA Univ Connecticut Farmington CT USA 06030 erapeut, Farmington,CT 06030 USA Univ Connecticut, Ctr Hlth, Dept Neurol, Farmington, CT 06030 USA Univ Connecticut Farmington CT USA 06030 Neurol, Farmington, CT 06030 USA Univ Connecticut, Ctr Hlth, Program Functional Neurolimaging, Farmington, CT 06030 USA Univ Connecticut Farmington CT USA 06030 maging, Farmington, CT 06030 USA
Titolo Testata:
HUMAN BRAIN MAPPING
fascicolo: 2, volume: 14, anno: 2001,
pagine: 116 - 127
SICI:
1065-9471(200110)14:2<116:PMOEFA>2.0.ZU;2-M
Fonte:
ISI
Lingua:
ENG
Soggetto:
INTRACEREBRAL POTENTIALS; VISUAL-STIMULI; FUNCTIONAL MRI; RARE TARGET; AUDITORY ODDBALL; PARIETAL CORTEX; P300; ACTIVATION; TIME; LOBE;
Keywords:
brain mapping; neuroimaging; cognition; attention; visual cortex; psychophysiology; arousal; event-related potentials; magnetic resonance imaging;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
39
Recensione:
Indirizzi per estratti:
Indirizzo: Clark, VP Univ Connecticut, Ctr Hlth, Dept Psychiat, MC2017,263 FarmingtonAve, Farmington, CT 06030 USA Univ Connecticut MC2017,263 Farmington Ave Farmington CT USA 06030
Citazione:
V.P. Clark et al., "Paradigm-dependent modulation of event-related fMRI activity evoked by theoddball task", HUM BRAIN M, 14(2), 2001, pp. 116-127

Abstract

We have previously shown that event-related functional magnetic resonance imaging (ER-fMRI) may be used to record responses to the rapid, interleavedpresentation of stimuli in the three-stimulus oddball task. The present study examined the sensitivity of ER-fMRI responses to variations in the range of inter-stimulus intervals (ISIs, calculated as the time from the offsetof one stimulus to the onset of the next stimulus) and the type of behavioral response task used. ISIs were varied between a wide ISI range (550-2,050 msec) and a narrow ISI range (800-1,200 msec), while maintaining a similar mean ISI (approximately 1 stimulus per sec) between experiments. The response task was varied between button press and subvocal target counting. Gradient echo, echo planar images were acquired for each of three experiments (wide ISI with button press, narrow ISI with button press, and wide-ISI with counting) in five subjects. Target stimuli generated increased fMRI signal in a wide range of brain regions. The use of a narrow ISI range generateda greater volume of subcortical activity and a reduced volume of cortical activity relative to a wide ISI range. The counting task generated a largeramplitude and longer lasting evoked response in brain regions that responded during all three experiments. Rare distractor stimuli evoked fMRI signalchange primarily in orbitofrontal, ventral-medial prefrontal and superior parietal cortex. These results illustrate that although ER-fMRI is relatively insensitive as a technique to small variations in the timing of stimulus-evoked responses, it is remarkably sensitive to consequences such variations have for the topographic location and amplitude of neural responses to stimuli.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 29/01/20 alle ore 19:23:17