|Vol. 7, No. 3, 2001 Page 5&6|
Brain scans of teens and young adults from alcoholism-prone families reveal abnormalities of the amygdala, according to a study by Shirley Hill and colleagues. The amygdala plays a critical role in emotion and cognition (see related article, Crime Times, 2001, Vol. 7, No. 3, Page 3).
Hill et al. performed MRI scans on 17 teenagers and young adults considered to be at high risk for developing alcoholism due to strong family histories of the disorder. They also conducted MRIs on 17 control subjects with no family histories of alcoholism. "High risk adolescents and young adults," they say, "showed reduced right amygdala volume in comparison with control subjects."
The researchers also found that right amygdala volume correlated significantly with visual P300 amplitude, a measure of brain electrical activity. Several studies indicate that children from families with a heavy "loading" of alcoholics exhibit reduced P300 amplitudes, an abnormality also tentatively linked to an increased risk of drug abuse and tobacco use.
Hill et al. note that the amygdala is part of a "reward circuit" within the brain, and that abnormalities in this circuit are implicated in some addictive behaviors. "Because the amygdala tends to increase in volume during childhood and adolescence," they say, "smaller volumes in high-risk children may indicate a developmental delay that parallels delays seen in visual P300 amplitude."
"Right amygdala volume in adolescent and young adult offspring from families at high risk for developing alcoholism," S. Y. Hill, M. D. De Bellis, M. S. Keshavan, L. Lowers, S. Shen, J. Hall, and T. Pitts, Biological Psychiatry, Vol. 49, No. 11, June 1, 2001, pp. 894-905. Address: Shirley Hill, Department of Psychiatry, University of Pittsburgh School of Medicine, 3811 O'Hara Street, Pittsburgh, PA 15213.
"Brain differences found in alcoholics' kids," Reuters News Service, June 8, 2001.
"Reward deficiency syndrome," Kenneth Blum, John G. Cull, Eric R. Braverman, and David E. Comings, American Scientist, March-April 1996. Address not listed.