Twenty-five male and 13 female patients with alcoholic Korsakoff's syndrome (AKS) were compared with age- and sex-matched non-Korsakoff chronic alcoholics and healthy volunteers in a neuropsychological study, which included computer-administered tests of cognitive function. The performance of male Korsakoff patients was significantly inferior to that of healthy male controls, not only in tests of memory, but also in visuo-perceptual tasks with a speed or motor component, and on category sorting and verbal fluency measures. Compared with male alcoholics, the performance of male Korsakoff patients was again inferior on similar tests. Female Korsakoff patients showed more extensive deficits compared with female controls, but differed less from matched female alcoholics.
The results suggest that, in addition to their amnesia, many Korsakoff patients have sustained widespread cognitive deficits, affecting particularly visuo-perceptual and abstracting functions, which are sensitive to cortical lesions. The range of deficits falls short of what may be regarded as ‘global’ in male, but probably not in female, Korsakoffs. The implications for a dual aetiology of AKS involving thiamine deficiency and other features associated with alcoholism, probably direct alcohol neurotoxicity, are discussed.