14 DAY TRIAL // Scientists have found that the brains of alcoholic individuals are smaller than those of non-alcoholic ones, due to their own heavy alcohol intake, but also to their parents' drinking.
The research made at the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of the National Institutes of Health (NIH) discovered that alcoholic individuals with no such family history do not have smaller brains.
"This is interesting new information about how biological and environmental factors might interact to affect children of alcoholics," said Dr. George Kunos M.D., Scientific Director, Division of Intramural Clinical and Biological Research, NIAAA.
The smaller brains of the alcoholics - fact also proved by previous studies - is thought to be determined by the toxic action of ethanol, which provokes their brain to shrink more with aging compared to that of non-alcoholic's. "Our study is the first to demonstrate that brain size among alcohol-dependent individuals with a family history of alcoholism is reduced even before the onset of alcohol dependence," said first author Jodi Gilman, Ph.D. candidate at Brown University.
Parents' alcoholism renders their children more prone to alcoholism than the children of non-alcoholic individuals. Besides the adverse genetics, the first children experience harmful biological and psychological factors like poor diets (from womb of the mother and after, delivered by alcoholic parents that usually disregard food), unstable parental relationships, and alcohol exposure before birth.
The team employed magnetic resonance imaging (MRI) to determine the cranial volume in a group of alcoholic patients. The intracranial volume (ICV) growth is completed around puberty and does change with the age, offering a good estimate of the lifetime maximum brain volume.
The average ICV of adult alcoholics with alcoholic parents was about 4 % lower than the average ICV of alcoholics without family histories of alcoholism.
Family history was not connected with the frequency, quantity, or other drinking patterns of the alcoholics themselves.
Alcoholics with alcoholic parents had an IQ level on average with 5.7 points less than IQs that of alcoholics with no parental drinking; but in both groups the IQ was anyway in the normal range of intelligence. "Although ICV is known to be influenced primarily by genetic factors, many studies have found that living in an enriched environment promotes central nervous system growth and development. It seems likely that alcoholics, in general, are raised in less than optimal environments and thus that genetics and environment both contribute to the smaller ICV observed in family history positive alcoholics", said senior author Dr. Daniel Hommer, of the NIAAA Laboratory of Clinical and Translational Studies (LCTS)
The women' ICV was found to be more sensitive to their mothers' drinking than to their fathers', as mothers play a higher role in the child's nutritional intake and social and intellectual development. "It is possible that some participants might have experienced subtle fetal alcohol effects. However, there were no differences between the effects of maternal and paternal drinking on ICV of men in our study. Thus, fetal alcohol effects do not appear to account for the reduced ICV we saw in men with a positive family history for drinking. Future studies should determine more precisely how parental drinking affects brain size among children of alcoholics and whether smaller ICV is a more specific risk factor for the development of alcohol dependence than family history." None of the subjects suffered from fetal alcohol syndrome (FAS).