Teen Brains More Susceptible to Drugs
Scientists have known for decades that teenagers are more likely to become addicted to drugs than any other group.
The explanation generally hinges around social circumstances – peer pressure, or the fact that parents who smoke are more likely to raise teen smokers, for instance. But two new papers, published together in eLife, argue the reason is more biological than previously thought.
The two studies assessed the role of elF2α, a molecule that regulates the production of proteins responsible for building connections between neurons. In one study, adolescent and adult mice were injected with either a saline solution or a low dose of cocaine. Researchers found only the adolescent mice that were given cocaine experienced a reduction of eIF2α activity, which resulted in changes in protein regulation that strengthened connections between dopamine-storing neurons.
Increased communication between dopamine-rich neurons increases the sense of pleasure from taking the drug, which in turn increases the likelihood of addiction.
The second study described similar experiments, but with nicotine instead of cocaine. The results were similar, but using functional magnetic resonance imaging, the study also identified a variation in the human gene that codes for eIF2α. This variation, they found, can either increase or decrease nicotine users’ responses to rewards.
The stated goal of both study groups is to educate adolescents about the very real risks of recreational drug use and experimentation.