52 recently abstinent chronic alcoholics were given repeated psychological tests and 20 of these had repeated CT scans. The first scan was done within 5 weeks of the last drink. The degree of measurably reversible cerebral atrophy on CT scan correlated negatively with the interval between the last drink and the first CT scan. Significantly more reversibility of cerebral atrophy was noted in those subjects claiming interscan abstinence. There were positive correlations between functional improvement scores on neurological exam and reversible cerebral atrophy measurements. Significant improvement on psychological test performance was restricted to patients tested initially within 3 weeks of the last drink. Both the CT results and the psychological test results suggest that reversible changes occur soon after the cessation of drinking.