Summary
In anaesthetized rabbits, the effects of VIIIth nerve stimulation were studied in the cervicothoracic segments of the spinal cord by recording spike field potentials representing the secondary vestibular volleys, postsynaptic potentials in spinal neurones and corresponding field potentials. It was revealed that an excitatory action was conveyed by the medial vestibulospinal tract (MVST) fibers bilaterally and also by the lateral vestibulospinal tract (LVST) fibers ipsilaterally. Both of these two excitatory fiber groups conducted the secondary vestibular volleys with relatively fast velocities. An inhibitory action was effected bilateraly by those MVST fibers which conducted secondary vestibular volleys with a relatively slow velocity, as previously described in oats. By direct stimulation of the medulla it was demonstrated that both excitatory and inhibitory MVST fibers arise from the middle portion of the vestibular nuclear complex in and around Deiters' nucleus.
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akaike, T., Fanardjian, V.V., Ito, M. et al. Electrophysiological analysis of the vestibulospinal reflex pathway of rabbit. II. Synaptic actions upon spinal neurones. Exp Brain Res 17, 497–515 (1973). https://doi.org/10.1007/BF00234864
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DOI: https://doi.org/10.1007/BF00234864