June 24, 2011

Cocaine’s effects on the teenage brain

Cocaine exposure during the teen years causes long-lasting brain and behavioral changes in rats.


Experimentation with drugs is common during the teen years. But the consequences of exposure to drugs like cocaine during this critical period for brain development remain unclear.

To understand how cocaine affects the developing adolescent brain, Christine Konradi, Stephanie Sillivan and colleagues administered escalating doses of cocaine to “teenage” rats over a 12-day period – a model of “binge” cocaine exposure.

When the rats reached adulthood, cocaine-exposed animals displayed decreased anxiety and fear-related learning – and increased levels of novelty-seeking – compared to untreated animals.

The investigators also analyzed gene expression changes in the amygdala – the brain region involved in the processing and memory of emotional events – and found that genes belonging to pathways involved in brain development and wiring were affected.

The results, published in Biological Psychiatry, suggest that cocaine exposure during adolescence may lead to mis-wiring in the developing brain and result in long-lasting behavioral problems, such as increased risk-taking, in adulthood.

The research was funded by the National Institute on Drug Abuse and the National Institute of Mental Health.