OBJECTIVE: To distinguish, in patients with Korsakoff syndrome (KS), the structural brain abnormalities shared with alcoholic patients without KS (AL), from those specific to KS. METHODS: MRI data were collected in 11 alcoholic patients with KS, 34 alcoholic patients without KS, and 25 healthy control subjects (CS). Gray and white matter volumes were compared in the 3 groups using a voxel-based approach. RESULTS: A conjunction analysis indicated a large pattern of shared gray and white matter volume deficits in AL and KS. There were graded effects of volume deficits (KS < AL < CS) in the medial portion of the thalami, hypothalamus (mammillary bodies), left insula, and genu of the corpus callosum. Abnormalities in the left thalamic radiation were observed only in KS. CONCLUSIONS: Our results indicate considerable similarities in the pattern of gray and white matter damage in AL and KS. This finding confirms the widespread neurotoxic effect of chronic alcohol consumption. Only a few cerebral regions, including the medial thalami, mammillary bodies, and corpus callosum, were more severely damaged in KS than in AL. The continuum of macrostructural damage from AL to KS is therefore restricted to key brain structures. Longitudinal investigations are required to determine whether alcoholic patients with medial thalamic volumes that are comparable to those of patients with KS are at increased risk of developing KS.