Study on vomiting related to the vestibulo-autonomic reflex

The purpose of this study was to investigate the neural pathway from the vestibular labyrinth to the medullary vomiting center in the cat, using electrophysiological techniques. During electrical stimulation of the canal nerve, we found conflicting results: the pressure in the stomach sometimes increased, and sometimes decreased. There might be several neural structures between the semicircular canal nerve and the vomiting center in the dorsolateral portion of the reticular formation of medulla oblongata. Retching or vomiting-like behavior during both respiration and movement of the stomach was recorded during stimulation at several sites in the lateral medullary reticular formation. However, the evoked unit activities were not always induced by stimulation of the canal nerve.