[Robert Bárány, Austrian physician and physiologist, 1876-1936. Awarded Nobel Prize in medicine in 1914]
Evaluation of vestibular function by irrigation of the ear canal with either warm or cold water. Normally when warm water is used, rotatory nystagmus toward the irrigated ear is observed; with cold water, the normal response is rotatory nystagmus away from the irrigated ear. If vestibular function is impaired, the response may be absent or diminished. If one ear is normal and the other is not, a comparison between the two may be made.