title: Late response evoked by cerebellar stimuli: effect of optokinetic stimulation.
abstract: We previously demonstrated that late electromyographic responses with a latency of 100 ms were evoked bilaterally in soleus muscles following transcranial magnetic stimulation over the left cerebellum. Efferent fibers from the left cerebellum modulate vestibulospinal tract influences on the extensor muscles of the left hindlimb. Here, we investigated whether the vestibulospinal tract mediates this late response. We activated the vestibulospinal tract by optokinetic stimulation. Our results show that the latency of the soleus electromyographic response is shortened by optokinetic stimulation, but the latency of the motor response evoked by the corticospinal tract is unchanged. These findings support our hypothesis that vestibulospinal tracts mediate late electromyographic responses, and allow the development of techniques to assess the human vestibulospinal system function.
authors.affiliation: Department of Functional Diagnostic Science, Osaka University Graduate School of Medicine, Yamadaoka, Suita, Osaka, Japan. sakihara@rehab.go.jp
authors.forename: Kotoe
authors.initials: K
authors.lastname: Sakihara
authors.forename: Masayuki
authors.initials: M
authors.lastname: Hirata
authors.forename: Seiji
authors.initials: S
authors.lastname: Nakagawa
authors.forename: Nobuko
authors.initials: N
authors.lastname: Fujiwara
authors.forename: Masaki
authors.initials: M
authors.lastname: Sekino
authors.forename: Shoogo
authors.initials: S
authors.lastname: Ueno
authors.forename: Aya
authors.initials: A
authors.lastname: Ihara
authors.forename: Shiro
authors.initials: S
authors.lastname: Yorifuji
mesh_terms: D000328:Adult; D002531:Cerebellum / Q000502:physiology*; D003627:Data Interpretation, Statistical; D004525:Efferent Pathways / Q000166:cytology / Q000502:physiology; D004576:Electromyography; D005260:Female; D006801:Humans; D007866:Leg / Q000294:innervation / Q000502:physiology; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology; D009434:Neural Pathways / Q000502:physiology; D017120:Nystagmus, Optokinetic / Q000502:physiology*; D010775:Photic Stimulation; D011187:Posture / Q000502:physiology; D014726:Vestibular Nuclei / Q000502:physiology*