Hi Kristin! This references back to the mnemonic COWS (Cold-Opposite, Warm-Same). Cold and warm water will induce different patterns of nystagmus due to the inhibition and excitation of the vestibular system, respectively. “Decreased left-beating nystagmus when the right ear is irrigated with warm water” is incorrect because introduction of warm water would induce right-beating nystagmus not left-beating nystagmus. And in the case of this patient with a right hypofunction, a reduced right-beating nystagmus compared to a normal reference point would be observed. Hopefully that clarified your question – happy to expand!
