It has been suggested in the literature from time to time that Wernicke's and Korsakoff's syndromes may be related. "Acute hemorrhagic polioencephalitis superior" has been firmly established as a distinct clinical and pathologic entity since its original description, in 1881, by Wernicke.1The characteristic picture of ophthalmoplegia, ataxia, confusional mental state, and often peripheral neuritis, occurring predominantly in alcoholic patients, and the necropsy findings of acute hemorrhagic lesions in the periventricular and periaqueductal areas of the thalamus, hypothalamus, and brain stem are well known. Korsakoff's psychosis, originally described in 1887,2characterized by memory impairment, temporal disorientation, and confabulation, with or without peripheral neuritis, also occurs most frequently in alcoholic patients. Athough this syndrome is more prevalent than Wernicke's form, it is clinically less specific and has not been defined adequately from a neuropathologic viewpoint. The purpose of the present study is to determine, if possible, the validity of