When processed by the rapid Golgi method, a significant reduction (P less than 0.002) of the dendritic arborization of Purkinje cells located at the tips of the folia of the rostral vermis was demonstrated in four human cases of cerebellar atrophy, related to chronic alcohol consumption. Except for isolated damaged Purkinje cells located on the depth of the sulci of the rostral vermis in all but one case, no significant differences were observed between alcoholic cases and controls of comparable ages among Purkinje cells located in the remainder of the vermis or the cerebellar hemispheres. These results suggest that structural changes, which precede neuronal death and cell loss, are present in Purkinje cells of the rostral vermis in human cerebellar alcoholic degeneration.