[Heat and vestibular stimulation]

In 1905 Barany analyzed the nystagmus that appears during the irrigation of the ear with cold and hot water, justifying the phenomenon due to convectives currents in the horizontal semicircular canal. This hypothesis has been widely accepted until doubt was casted on it by the experiences carried out in the Skylab. Of the various mechanisms that could be responsible for the vestibular stimulation in the caloric tests, those which entail convection currents or endolymph expansion would need--we think--thermal gradients very superior to those occurring during these tests, that according to our calculations--always pro such hypothesis--seem insufficient.