Response of gamma and alpha motor systems to phasic and tonic vestibular inputs
1967; Elsevier BV; Volume: 6; Issue: 3 Linguagem: Inglês
10.1016/0006-8993(67)90064-9
ISSN1872-6240
Autores Tópico(s)Hearing, Cochlea, Tinnitus, Genetics
ResumoResponses in alpha and gamma lumbar motoneurons were recorded during quantifiable natural vestibular stimulation, in decerebrated cats, after destruction of the contralateral labyrinth. It was shown that the phasic responses of gamma motoneurons reach a maximum at approximately 0.5 sec after application of the stimulus, their intensity being dependent only on the angular velocity of head rotation. These features are predictable if it is assumed that this phasic response is due to activities originating in the ampullar receptors of the semicircular canals. The intensity of the tonic responses of both alpha and gamma motoneurons was found, on the contrary, to depend on the degree of angular rotation of the head, suggesting therefore their dependence upon macular receptor activity. The alpha and gamma motoneurons exhibited an independent behavior in response to natural vestibular stimulations, as revealed by the following evidence: (a) Responses were consistently present in the gamma but not in the alpha motor system. (b) There was no simple correlation between degree of gamma motor response and the changes in the alpha motor system. (c) Dorsal root section did not abolish alpha motor response to vestibular stimulation.
Referência(s)