Downbeat Nystagmus Is Abolished by Alcohol in Nonalcoholic Wernicke Encephalopathy

Background and Objectives Lesions of the cerebellar flocculus cause enduring downbeat nystagmus (DBN) with unrelenting oscillopsia. Unlike most patients with DBN, the flocculus is structurally spared in nonalcoholic Wernicke encephalopathy (nWE) with chronic DBN. The objective was to study the effects of alcohol in nWE. Methods We recorded eye movements of a unique patient with nWE under controlled alcohol consumption who said his oscillopsia disappeared with a few drinks of alcohol. Results His DBN was markedly diminished by alcohol (by 77.4%), although he remained alert with normal saccades. Discussion This striking observation may be caused by the differential effect of alcohol on the peri-hypoglossal complex and the paramedian tract neurons, which control the level of activity in the flocculus, with opposite (inhibition and excitation, respectively) effects. The finding suggests new ideas about the treatment and pathophysiology of DBN with a structurally intact cerebellum.

Automated summary

This study investigated the effects of alcohol on patients with nonalcoholic Wernicke encephalopathy (nWE) and observed a significant improvement in DBN with alcohol consumption. The findings may be attributed to the differential effects of alcohol on the cerebellar regions, providing new insights into the treatment and pathophysiology of DBN.