Stimulation of the nodulus and uvula discharges velocity storage in the vestibulo-ocular reflex

David Solomon, Bernard Cohen

Research output: Contribution to journalArticlepeer-review

Abstract

The nodulus and sublobule d of the uvula of rhesus and cynomolgus monkeys were electrically stimulated with short trains of pulses to study changes in horizontal slow-phase eye velocity. Nodulus and uvula stimulation produced a rapid decline in horizontal slow phase velocity, one aspect of the spatial reorientation of the axis of eye rotation that occurs when the head is tilted with regard to gravity during per- and post-rotatory nystagmus and optokinetic after-nystagmus (OKAN). Nodulus and uvula stimulation also reproduced the reduction of the horizontal time constant of post-rotatory nystagmus and OKAN that occurs during visual suppression. The brief electric stimuli (4-5 s) induced little slow-phase velocity and had no effect on the initial jump in eye velocity at the onset or the end of angular rotation. Effects of stimulation were unilateral, suggesting specificity of the output pathways. Activation of more caudal sites in the uvula produced nystagmus with a rapid rise in eye velocity, but the effects did not outlast the stimulus and did not affect VOR or OKAN time constants. Thus, stimulation of caudal parts of the uvula did not affect eye velocity produced by velocity storage. We postulate that the nodulus and sublobule d of the uvula control the time constant of the yaw axis (horizontal) component of slow-phase eye velocity produced by velocity storage.

Original languageEnglish (US)
Pages (from-to)57-68
Number of pages12
JournalExperimental Brain Research
Volume102
Issue number1
DOIs
StatePublished - Jan 1994

Keywords

  • Monkey
  • Nodulus
  • Uvula
  • Velocity storage
  • Vestibulo-ocular reflex

ASJC Scopus subject areas

  • Neuroscience(all)

Fingerprint Dive into the research topics of 'Stimulation of the nodulus and uvula discharges velocity storage in the vestibulo-ocular reflex'. Together they form a unique fingerprint.

Cite this