同一筋収縮方向の違いによる運動誘発電位の変化 <DESCRIPTIVE INVESTGATION>

Effects of Voluntary Motor Command on Motor Evoked Potentials (MEPs) of Multifunction Muscle

Yahagi Susumu

Kasai Tatsuya

Kato Takashi

Japanese journal of sports sciences

Using the technique of transcranial magnetic stimulation motor evoked potentials (MEPs) were studied in the first dorsal interosseous(FDI) muscle of human subject. The question was asked how the central nervous system control a multifunction muscle for performing the aimed voluntary movement. Main findings are followings: 1) differences of MEP amplitude were observed among different directions of finger movement, 2) however, there were remarkable different FDI contributions to performing their movements, 3) then, while we retested them by control the background EMG discharge, MEP amplitudes were dependent on amount of targeted muscle activity, 4) under a certain condition there were significant differences of MEP amplitude between flexion and abduction of index finger. Taken together, present results confirmed the former principle suggested by Desmedt and Godaux (1981), i.e., the active excitatory synapses for flexion commands are larger distirubuted troughout the same motoneuron pool than those of abduction. Therefore, MEPs might be reflected on synaptic connectivities of voluntary motor commands in motoneuron pool.

Sports and physical training [ 780 ]

jpn

日本バイオメカニクス学会

[ISSN] 0286-9322

[NCID] AN00388432