This study investigated which cognitive deficits are associated with chronic alcoholism. Neuropsychological profiles and MRI brain structure volumes of 14 patients with Korsakoff's syndrome, 15 patients with chronic alcoholism, and 16 healthy control subjects were compared. The patients with alcoholism had a normal cognitive performance and normal brain structure volumes. The patients with Korsakoff's syndrome had performance deficits on tests of memory, visuoperceptual, and executive functions, as well as reduced brain structure volumes. The results suggest that the cognitive deficits cannot be ascribed to mere chronic consumption of alcohol. If cognitive deficits are present in patients with chronic alcoholism, this may point to an underlying brain disorder.