Labyrinthine stimulation causes: Nystagmus Past pointing Falling
Cold caloric stimulation causes nystagmus with the fast phase away from the stimulated ear. Warm caloric stimulation causes nystagmus with the fast phase towards the stimulated ear.
A head back tilt of 60 degrees brings the lateral semicircular canal into the vertical plane, as it is angled at 30 degrees to the horizontal plane. Instillation of water at 44 C causes heat transfer to the lateral semicircular canal. This produces convection currents in the endolymph.
A slow drift of the eyes away from the stimulated side is followed by a rapid recovery to the resting position.
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