Brain Differences Detected in Alcoholics' Kids
By Keith Mulvihill

NEW YORK (Reuters Health) - Brain scans of children who come from families with several generations of alcohol dependence reveal differences in a region of the brain associated with basic emotions, researchers have found.

Dr. Shirley Y. Hill of the University of Pittsburgh, Pennsylvania and colleagues published the findings in the June issue of the journal Biological Psychiatry.

``The paper is the first demonstration that a brain structure that is part of a circuit that is involved in both emotion and cognition may be smaller in adolescents from families with a high loading of alcohol dependence before they drink,'' Hill told Reuters Health.

In the study, Hill's team conducted MRI scans on 17 teens considered to be at high risk of alcohol dependence due to a strong family history of alcoholism. The average age of the participants was 17 years, and none had ever consumed alcohol. The study participants were compared with 17 teens without a family history of alcoholism.

Those with a family history of alcoholism were found to have a reduction in the size of the right side of an area of the brain called the amygdala--a walnut-sized region that is known to control basic emotions.

``When we looked at some of the children who hadn't had any drugs or alcohol to speak of, the same pattern of smaller right amygdala volume was seen,'' Hill told Reuters Health. ``Why the right amygdala? We are not sure.''

The amygdala is part of a ``reward circuit'' within the brain that has been implicated in some addictive behaviors, including cocaine use and gambling, Hill said. The smaller size of the amygdala could indicate a developmental delay that affects this circuit, she added.

Hill noted that work by other researchers suggests that the right amygdala may be growing more during adolescence and that brain development in these teens may catch up to normal proportions by adulthood.

``The other important point is that the teens we studied were on average quite bright with above-average IQ and came from middle to upper-middle class families,'' Hill said in the interview.

``In spite of these advantages, they carry a greater than average susceptibility for developing alcohol dependence because of the family history of alcohol dependence,'' she pointed out.

``Prevention is clearly the way to go in preventing the transmission across generations,'' Hill concluded.

SOURCE: Biological Psychiatry 2001;49:894-905.