Distinct cortical areas for motor preparation and execution in human identified by Bereitschaftspotential recording and ECoG-EMG coherence analysis.
OBJECTIVE
To clarify the cortical areas involved in motor preparation and execution by investigating Bereitschaftspotentials (BPs) and electrocorticogram-electromyogram (ECoG-EMG) coherence from subdural electrodes placed around the rolandic area.


METHODS
BPs and ECoG-EMG coherence were investigated for presurgical evaluation in a patient with cavernoma in the left frontal lobe. BPs were recorded in association with the tongue, right hand and right foot movements. ECoG-EMG coherence was calculated in association with weak muscle contraction of the right hand.


RESULTS
Two cortical areas related to voluntary motor control were identified; one in the primary hand motor area, which generated surface-negative BPs with hand movements and showed significant coherence of ECoG with EMG of the contralateral hand muscle, and the other in the ventral rolandic area posterior to the central sulcus, which generated surface-positive BPs with voluntary movements of multiple sites (hand, tongue and foot) but did not show any ECoG-EMG coherence.


CONCLUSIONS
It is postulated that the former area represents the primary motor area involved in both motor preparation and execution, and the latter area represents the non-primary motor area involved in motor preparation.


CONCLUSIONS
BP recording combined with ECoG-EMG coherence analysis could reveal the functional roles of motor cortices and the reorganization induced by structural brain lesion.
Satow
Takeshi
T
Human Brain Research Center, Kyoto University Graduate School of Medicine, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
Matsuhashi
Masao
M
Ikeda
Akio
A
Yamamoto
Junichi
J
Takayama
Motohiro
M
Begum
Tahamina
T
Mima
Tatsuya
T
Nagamine
Takashi
T
Mikuni
Nobuhiro
N
Miyamoto
Susumu
S
Hashimoto
Nobuo
N
Shibasaki
Hiroshi
H
D001931:Brain Mapping; D001932:Brain Neoplasms / Q000503:physiopathology*; D003265:Contingent Negative Variation; D004566:Electrodes; D004569:Electroencephalography / Q000379:methods*; D004576:Electromyography / Q000379:methods*; D019054:Evoked Potentials, Motor; D005528:Foot / Q000503:physiopathology; D007839:Functional Laterality; D006225:Hand / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000503:physiopathology*; D009119:Muscle Contraction / Q000502:physiology; D014059:Tongue / Q000503:physiopathology