Abstract:
:The role of relative cerebral blood volume (rCBV) in the early response of blood oxygenation level-dependent (BOLD) signal following sensory stimulation was assessed. Magnetic resonance imaging (MRI) measurements of rCBV and BOLD signal as a function of time (t) were compared with relative cerebral blood flow (rCBF) obtained by laser doppler flowmetry during a repeated epoch of rat forepaw stimulation in which 6 sec of electrical stimulation followed 54 sec of rest. rCBF(t) exceeded rCBV(t) in somatosensory cortex at all time points and reached a maximal increase (60%) during a 6 sec stimulation that was much higher than maximal rCBV (10%). An initial dip was not observed in BOLD signal, which showed a delay with respect to rCBF that was roughly consistent with the cerebral blood transit time.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Marota JJ,Ayata C,Moskowitz MA,Weisskoff RM,Rosen BR,Mandeville JBdoi
10.1002/(sici)1522-2594(199902)41:2<247::aid-mrm6>subject
Has Abstractpub_date
1999-02-01 00:00:00pages
247-52issue
2eissn
0740-3194issn
1522-2594pii
10.1002/(SICI)1522-2594(199902)41:2<247::AID-MRM6>journal_volume
41pub_type
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