One approach to explaining the inconsistency in test results has been to test different subgroups of alcoholics that are defined based on one or more of these variables. Researchers look for differences in the degree of cognitive impairment manifested (as indicated by the test scores) by each of the various groups. However, conclusive evidence has yet to be found to support the possibility that any one of these variables alone could completely and consistently account for alcoholics’ cognitive impairments (Parsons 1993). Thus, the most plausible hypothesis is that cognitive deficits in alcoholics result from prolonged alcohol ingestion, which impairs the way the brain normally works (i.e., the functional brain states) in certain vulnerable alcoholics. Characterizing what makes certain abstinent alcoholics vulnerable remains open for debate.
