Teens Get A Rush From … Learning?

According to a new study, teenagers make poor decisions and engage in risky behavior because, in essence, they get a thrill out of learning from their mistakes.

So why don’t they get the same buzz from learning by trial and error in math class? Apparently, we’ll have to wait for further research to answer that one.

Russell Poldrack, PhD, of the University of Texas at Austin, professor of psychology and neurobiology and director of the university’s Imaging Research Center, collaborated on the study with researchers from UCLA. The results were published online in the journal Nature Neuroscience.

Study subjects ranging in age from 8 to 30 performed a learning task. They were asked to place an abstract image into one of two categories. They were told whether their answers were correct and were given money for each correct answer.

The researchers actually wanted to know how each participant’s brain reacted to “reward prediction error”—the difference between an expected outcome of an action and the actual outcome. “Learning seems to rely on prediction error,” said Dr. Poldrack, “because if the world is exactly as you expected it to be, there is nothing new to learn.”

The researchers used functional MRI to read “positive prediction error signals” in the study participants’ brains as the participants learned the results of their answers and the size of their rewards. “Our results raise the hypothesis that these risky behaviors, such as experimenting with drugs or having unsafe sex, are actually driven by overactivity in the mesolimbic dopamine system, a system which appears to be the final pathway to all addictions, in the adolescent brain,” Dr. Poldrack said.

Previous studies have shown that teens tend to be more sensitive to rewards than either children or adults and that dopamine is important for the motivation to seek rewards. Among the age groups in the new study, teens showed the highest spikes in prediction error signals, which probably meant they had the largest dopamine response, according to the researchers.

Basically, the teen response seemed to be: “So if I do this, then that happens? Cool!”

Can teens simply blame their bad decisions on their biology? Said Dr. Poldrack: “That’s a question for the philosophers.”

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