The implicit claim of the continuum hypothesis is that cognitive-functioning impairments should correlate with the extent of alcohol consumption. Assuming that alcohol-related structural brain changes account for cognitive decline, it would be expected that specific measures of prior alcohol consumption—such as quantity of drinks consumed per day, frequency (i.e., number of drinking days per week), and duration (i.e., number of years) of drinking—would correlate with test performance among alcoholics. Researchers who study alcohol-related cognitive changes have not reported this consistently. However, when a significant correlation is found between cognitive functioning in alcoholics and some measure of alcohol consumption, it is usually in the expected direction—that the greater the consumption of alcohol, the worse the performance on cognitive tasks.
