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Titolo:
Exploring the temporal nature of hemodynamic responses of cortical motor areas using functional MRI
Autore:
Samuel, M; Williams, SCR; Leigh, PN; Simmons, A; Chakraborti, S; Andrew, CM; Friston, KJ; Goldstein, LH; Brooks, DJ;
Indirizzi:
Hammersmith Hosp, MRC, Cyclotron Unit, London W12 0NN, England HammersmithHosp London England W12 0NN on Unit, London W12 0NN, England Inst Psychiat, Dept Clin Neurosci, London, England Inst Psychiat London England chiat, Dept Clin Neurosci, London, England Inst Psychiat, MR Res Inst, London, England Inst Psychiat London England nst Psychiat, MR Res Inst, London, England Inst Neurol, London, England Inst Neurol London EnglandInst Neurol, London, England Inst Psychiat, Dept Psychol, London SE5 8AF, England Inst Psychiat London England SE5 8AF pt Psychol, London SE5 8AF, England
Titolo Testata:
NEUROLOGY
fascicolo: 6, volume: 51, anno: 1998,
pagine: 1567 - 1575
SICI:
0028-3878(199812)51:6<1567:ETTNOH>2.0.ZU;2-D
Fonte:
ISI
Lingua:
ENG
Soggetto:
POSITRON EMISSION TOMOGRAPHY; CEREBRAL BLOOD-FLOW; FMRI TIME-SERIES; PARKINSONS-DISEASE; NEURONAL-ACTIVITY; MOVEMENTS; CORTEX; STIMULATION; POTENTIALS; SELECTION;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Clinical Medicine
Life Sciences
Citazioni:
33
Recensione:
Indirizzi per estratti:
Indirizzo: Samuel, M Hammersmith Hosp, MRC, Cyclotron Unit, Du Cane Rd, London W12 0NN, England Hammersmith Hosp Du Cane Rd London England W12 0NN 0NN, England
Citazione:
M. Samuel et al., "Exploring the temporal nature of hemodynamic responses of cortical motor areas using functional MRI", NEUROLOGY, 51(6), 1998, pp. 1567-1575

Abstract

Objective: To use functional MRI (fMRI) to study grouped patterns of cerebral activation and the course of hemodynamic responses during performance of two activation tasks (paradigms) using a hand-held joystick to perform movements in a repetitively fixed direction and movements in freely selected random directions. Background: Evidence from lesion, electrophysiologic, and functional imaging studies implicates prefrontal and mesial frontal cortex in motor preparation and primary motor cortex in motor execution, fMRI can be used to study cerebral activation and has practical advantages over other methods of functional neuroimaging. Methods: We acquired 100 multisliceT2*-weighted data sets from five healthy volunteers during performance of each paradigm using conventional fMRI. For each paradigm, rest and movementepochs were alternated every 30 seconds. After coregistration and spatial normalization, we combined the data for group studies. We used statistical parametric mapping to compare the early (first 15 seconds) components of the movement epochs with rest as well as the late (last 15 seconds) components of the movement epochs with rest. Results: During the early phase of bothparadigms, significant activation was present in rostral and caudal mesialpremotor cortex. Right prefrontal cortex was significantly activated during the early component of freely selected joystick movements. Activation of rostral supplementary motor area was maintained during the late component of freely selected movements but decreased during repetitively fixed movements. In contrast, significant activation in contralateral sensorimotor cortex was maintained during both early and late components of both paradigms. Conclusions: fMRI can detect cortical activation. The temporal resolution offMRI also allows adaptation of blood oxygenation level-dependent (BOLD) contrast signal to be detected in association cortex. However, the level of BOLD contrast signal in primary motor cortex remained significantly elevatedthroughout task performance.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 03/04/20 alle ore 04:32:59