Anatomical congruence of metabolic and electromagnetic activation signals during a self-paced motor task: A combined PET-MEG study
NeuroImage. 1998-05-01; 7(4): 337-351
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1. Neuroimage. 1998 May;7(4 Pt 1):337-51.
Anatomical congruence of metabolic and electromagnetic activation signals during
a self-paced motor task: a combined PET-MEG study.
Joliot M(1), Crivello F, Badier JM, Diallo B, Tzourio N, Mazoyer B.
(1)Service Hospitalier Frédéric Joliot, CEA, DSV, DRM, Orsay, France.
We have investigated the degree of spatial correlation between the cerebral blood
flow variations measured by positron emission tomography (PET) and the
electromagnetic sources as measured by magnetoencephalography (MEG) in five
subjects while performing a self-paced right index finger tapping task. Data were
processed independently for each technique using both single-case and
intersubject analysis. PET and MEG were coregistered with anatomical magnetic
resonance images for each subject. Both extension and flexion motor-related
fields were extracted from the MEG signal. Using the single dipole model we
identified the motor evoked field 1 (MEF1) in all subjects and the motor field
(MF) in three subjects. Individual and intersubject averaged PET data showed
consistent contralateral primary sensorimotor (PSM) hand area and bilateral
supplementary motor area activation. MEG individual and intersubject averaged
results demonstrated that both MEF1 and MF dipoles were localized within the PSM
PET activated area. Individual PSM mass center to dipole distance was 12 and 15.3
mm on average for the MEF1 and the MF component, respectively. For the same
components, the intersubject averaged analysis shows distances between the PET
Z-score maximum and the dipole locations of 6.3 and 15.0 mm, respectively. These
results show that PET and MEG MEF1 activation signals spatially coincide within
instrumental, registration, and modeling errors.
PMID: 9626674 [Indexed for MEDLINE]