Neural correlates of regional EEG power change.
To clarify the physiological significance of task-related change of the regional electroencephalogram (EEG) rhythm, we quantitatively evaluated the correlation between regional cerebral blood flow (rCBF) and EEG power. Eight subjects underwent H2 15O positron emission tomography scans simultaneously with EEG recording during the following tasks: rest condition with eyes closed and open, self-paced movements of the right and left thumb and right ankle. EEG signals were recorded from the occipital and bilateral sensorimotor areas. Cortical activation associated with EEG rhythm generation was studied by the correlation between rCBF and EEG power. There were significant negative correlations between the sensorimotor EEG rhythm at 10-20 Hz on each side and the ipsilateral sensorimotor rCBF and between the occipital EEG rhythm at 10-20 Hz and the occipital rCBF. The occipital EEG rhythm showed a positive correlation with the bilateral medial prefrontal rCBF, while the right sensorimotor EEG rhythm showed a positive correlation with the left prefrontal rCBF. In conclusion, decrease in the regional EEG rhythm at 10-20 Hz might represent the neuronal activation of the cortex underlying the electrodes, at least for the visual and sensorimotor areas. The neural network including the prefrontal cortex could play an important role to generate the EEG rhythm.
Oishi
N
N
Human Brain Research Center, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan.
Mima
T
T
Ishii
K
K
Bushara
K O
KO
Hiraoka
T
T
Ueki
Y
Y
Fukuyama
H
H
Hallett
M
M
D000328:Adult; D001143:Arousal / Q000502:physiology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000502:physiology; D004292:Dominance, Cerebral / Q000502:physiology; D004569:Electroencephalography; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D009044:Motor Cortex / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology; D009415:Nerve Net / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology; D009474:Neurons / Q000502:physiology; D009778:Occipital Lobe / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology; D049268:Positron-Emission Tomography; D017397:Prefrontal Cortex / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology; D012016:Reference Values; D012039:Regional Blood Flow / Q000502:physiology; D012815:Signal Processing, Computer-Assisted; D013003:Somatosensory Cortex / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology; D013223:Statistics as Topic; D009435:Synaptic Transmission / Q000502:physiology*