Life is dangerous as a teenager. At the same time as we’re learning to drive, we’re prone to risker behavior and more likely to make impulsive decisions than when we are children or adults. Neurologists have noticed that a small region of our brain is activated once we’ve made an impulsive decision: ‘Yes I will have that cigarette,’ or ‘watching TV sounds so much better than doing homework.’
This region, called the ventral striatum, is associated with feeling rewarded, happy, fulfilled and excited. Psychologists and brain science researchers believe the ventral striatum is especially active in adolescents. Some have proposed that neural sensitivity, higher in some individuals, can push people toward self-destructive risky or selfish behaviors.
But this, says Eva Telzer of the University of Illinois at Urbana-Champaign, isn’t the full story. “We show for the first time that within a sample of teenagers, activation in this same region can be both a source of risk and resilience,” she says. Telzer and her colleagues present their findings in Proceedings of the National Academy of Science.
Adolescents are not universally selfish, after all. Many assist their family (e.g. caring for siblings) do community service and express gratitude. These sorts of eudaimonic decisions (as opposed to hedonic) are linked with lasting feelings of meaning and purpose. Telzer’s past research has found heightened ventral striatum activation during prosocial family decisions.
In the current study Telzer and her colleagues asked a group of about 40 teenagers between 15 and 17 to play games while undergoing a brain scan. In one they decided how much money to donate to their family. Another, designed to study risk-taking tendency, they inflated a virtual ballon. The larger the ballon when they cashed out, the more money they earned, but over inflating made the balloon likely to burst. The teens also self reported their general well being in a questionnaire designed to assess depressive symptoms (e.g. “I don’t have much energy,” “I cry a lot.”) One year later they measured depressive symptoms again to see how they group had changed over time.
The teenagers who showed stronger ventral striatum activation when making prosocial decisions were less depressed one year later. (Even though striatal response had not been associated with depressive symptoms at the time of the original testing.) The researchers believe this “may represent a motivational orientation toward engaging in inherently meaningful activities that may increase feelings of value, meaningfulness, and intrinsic reward, therefore providing psychological and social resources and leading to better well-being over time.” This harmonizes with psychological theories that eudaimonic activities builds a person’s self-esteem, giving them feelings of mastery, competence, fulfillment and better relationships. Individuals who felt rewarded when making selfish or risky decisions felt more depressed over time.
“Taken together,” the authors write, “our findings suggest that well-being may depend on attending to higher values related to family, culture, and morality, rather than to immediate, selfish pleasure.”
But teenagers may not be able to help how they feel, so rather than trying to change the way they process rewards, Telzer suggests providing more opportunities for adolescents to engage in activities that cultivate meaningful feelings.