In most studies of alcohol-related neurological disorders, researchers have assessed neuropsychological deficits in alcoholics without examining changes in alcoholics’ brains. To better understand brain-behavior relationships, however, neuropsychological, structural, and functional changes must be evaluated to relate changes in behavior to damage in particular systems of the brain. In studies using both methods, in fact, results have not revealed consistent relationships between cortical damage and performance on neuropsychological tests. Some measures of brain structure or function have correlated with cognitive test scores, whereas others have not. For example, one study reported a relationship between certain neuropsychological test scores and measures of frontal brain metabolism in long-term alcoholics; the same study, however, found no correlation between neuropsychological performance and degree of cortical atrophy as seen using MRI (Wang et al. 1993). The results were interpreted as reflecting either the preservation of cognitive abilities with mild structural brain changes or the insensitivity of the tests used to detect mild structural changes.
