This brief article reviews the present state of knowledge concerning the relationship between structural and functional cerebral abnormalities and the cognitive deficits associated with multiple sclerosis. Currently available neuroimaging techniques have substantially contributed to a better understanding of the latter, suggesting that cortical-subcortical disconnection is the most likely cause of the cognitive disturbance. Longitudinal studies are needed to determine the natural history of the cognitive deficit and its relationship to the cerebral changes detected by neuroimaging techniques.