Brain's Judgment Center Smaller in Coke Addicts
Low-volume amygdala may predispose some to addiction
WEDNESDAY, Nov. 17, 2004 (HealthDayNews) -- Cocaine addicts have a smaller amygdala -- a brain structure that helps people judge the consequences of their actions -- than non-addicted people, claims research in the current issue of Neuron.
"These observations are relevant, because cocaine-dependent subjects have significant difficulty identifying the potential negative outcomes of their behavior or acknowledging that these outcomes could transpire," the researchers noted.
Using magnetic resonance imaging (MRI), the investigators scanned the brains of 27 cocaine addicts and 27 non-addicts. They found the amygdalas of the cocaine addicts were an average 13 percent smaller on the left side of the brain, and 23 percent smaller on the right side of the brain, compared to the amygdalas of the non-addicts.
The investigators couldn't determine conclusively whether cocaine addiction results in a smaller amygdala, or whether people with smaller amygdalas are more likely to become addicts. However, they believe the findings indicate that reduced amygdala volume may occur before the onset of addiction.
Family-based studies, as well as longitudinal studies of cocaine addicts, should be able to confirm whether or not that theory is correct, the researchers said.
The U.S. National Institute on Drug Abuse has more about cocaine abuse and addiction.