Temporal facilitation prior to voluntary muscle relaxation.
We investigated the dominancy of excitability changes in motor cortex or spinal levels and temporal tuning mechanisms of muscle relaxation. We delivered transcranial magnetic stimulation and electric (H-reflex) stimulations relative to the application of the response signal under the reaction time task. The results showed that a significant change was found in only motor evoked potential during the prerelaxation phase, 30 ms after the response signal presented for muscle relaxation, but similar changes were not found in H-reflex. We suggested that this phenomenon, may be, reflects on excitation of corticospinal neurons, which consequently play an important role for muscle relaxation.
Sugawara
Kenichi
K
School of Rehabilitation, Faculty of Health and Social Work, Kanagawa University of Human Services, Yokosuka, Kanagawa, Japan. sugawara-k@kuhs.ac.jp
Tanabe
Shigeo
S
Higashi
Toshio
T
Tsurumi
Takamasa
T
Kasai
Tatsuya
T
D000328:Adult; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D006181:H-Reflex / Q000502:physiology; D006801:Humans; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D009046:Motor Neurons / Q000502:physiology; D009068:Movement / Q000502:physiology; D009119:Muscle Contraction / Q000502:physiology; D009126:Muscle Relaxation / Q000502:physiology*; D009129:Muscle Tonus / Q000502:physiology*; D018482:Muscle, Skeletal / Q000294:innervation / Q000502:physiology*; D009431:Neural Conduction / Q000502:physiology; D009483:Neuropsychological Tests; D011712:Pyramidal Tracts / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D013997:Time Factors; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult