SUMMARY A range of volumetric and neurochemical analyses were carried out on the brains of 14 "moderate" drinkers. These data were compared with previous studies from controls and alcoholics. Volumetric measurements consistently suggest a loss of cerebral tissue although the differences were not statistically significant. Changes in the lipid and water content of the white matter were noted and the significance of these changes in relation to the pathogenesis of reversible brain shrinkage caused by alcohol abuse is discussed.There is a considerable volume of clinical, 1 2 neuroradiological,34 neuropsychological' and neuropathological6 -data concerning the long term effects of alcohol abuse on the human central nervous system. A large proportion of these data, particularly with regard to neuropathological changes, deals with severe chronic alcoholism. The interpretation of such data is difficult because of the frequency of occurrence of attendant disorders such as cirrhosis of the liver and nutritional deficiency disorders (Wernicke's encephalopathy) in the more advanced cases of alcoholism. Of particular interest to the general public is the long term effects of a moderate alcohol intake which many would equate with "social" drinking.
Materials and methodsCases for the studies cited in this paper were The procedures and techniques utilised in determining the various parameters have been described in previous papers relating to changes in the alcoholic groups.9 1 -20 Samples from the frontal, parietal and occipital white matter of the right hemisphere were used for the various neurochemical assays. The water content was determined by weighing the tissue before and after drying to a constant weight.2' The dried residue was acid digested and the sodium and potassium concentration determined by flame photometry. Although there is a considerable amount of additional information included in the tabular data the principal aim of this paper is to address the issue of the pathological changes in the brains of men regularly drinking between 30 and 80 grams of alcohol per day. The control and alcohol data are used for comparison.