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The Young Brain—Why Does it Take So Long to Grow Up? January 30, 2012

Posted by Nina Rosenstand in Education, Nina Rosenstand's Posts, Philosophy of Human Nature, Science.
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Welcome to the Spring 2012 semester, where we will post occasional blog entries as our schedules and moods allow! Here is something that I think will interest those of you who are under 25, or happen to know someone who is! Finally we understand the adolescent brain, and furthermore, that the adolescent brain will last well into young adult years these days, because what makes a brain “adult” is that is has responsibilities. Uh-oh! Does that mean some people will never grow up? Maybe…and there is a name for that: the Peter Pan Syndrome. Perhaps there will be a neurological explanation for that, now…

But in the meantime, this is what professor of psychology Alison Gopnik writes in her article, “What’s Wrong With the Teenage Mind?”: Puberty is happening earlier, but adulthood seems to be delayed. So we will have to live with “teenage weirdness” longer than in past centuries.

The crucial new idea is that there are two different neural and psychological systems that interact to turn children into adults. Over the past two centuries, and even more over the past generation, the developmental timing of these two systems has changed. That, in turn, has profoundly changed adolescence and produced new kinds of adolescent woe. The big question for anyone who deals with young people today is how we can go about bringing these cogs of the teenage mind into sync once again.

The first of these systems has to do with emotion and motivation. It is very closely linked to the biological and chemical changes of puberty and involves the areas of the brain that respond to rewards.

Recent studies in the neuroscientist B.J. Casey’s lab at Cornell University suggest that adolescents aren’t reckless because they underestimate risks, but because they overestimate rewards—or, rather, find rewards more rewarding than adults do. The reward centers of the adolescent brain are much more active than those of either children or adults. Think about the incomparable intensity of first love, the never-to-be-recaptured glory of the high-school basketball championship.

The second crucial system in our brains has to do with control; it channels and harnesses all that seething energy. In particular, the prefrontal cortex reaches out to guide other parts of the brain, including the parts that govern motivation and emotion. This is the system that inhibits impulses and guides decision-making, that encourages long-term planning and delays gratification.

This control system depends much more on learning. It becomes increasingly effective throughout childhood and continues to develop during adolescence and adulthood, as we gain more experience. You come to make better decisions by making not-so-good decisions and then correcting them.

In the past (from hunter-gatherers all the way to the recent past) those two systems were in sync, but they are no longer.

The experience of trying to achieve a real goal in real time in the real world is increasingly delayed, and the growth of the control system depends on just those experiences. The pediatrician and developmental psychologist Ronald Dahl at the University of California, Berkeley, has a good metaphor for the result: Today’s adolescents develop an accelerator a long time before they can steer and brake.

This doesn’t mean that adolescents are stupider than they used to be. In many ways, they are much smarter. An ever longer protected period of immaturity and dependence—a childhood that extends through college—means that young humans can learn more than ever before. There is strong evidence that IQ has increased dramatically as more children spend more time in school, and there is even some evidence that higher IQ is correlated with delayed frontal lobe development….

But there are different ways of being smart. Knowing physics and chemistry is no help with a soufflé. Wide-ranging, flexible and broad learning, the kind we encourage in high-school and college, may actually be in tension with the ability to develop finely-honed, controlled, focused expertise in a particular skill, the kind of learning that once routinely took place in human societies. For most of our history, children have started their internships when they were seven, not 27.

Recognize the problems of Will Hunting in Good Will Hunting? He has all the theoretical knowledge in the world, but has no idea how to live (and doesn’t even dare to). So what to do about it? Gopnik suggests to increase the level of varied hands-on experience of the young person, an extended apprenticeship-adolescence with responsibilities:

Instead of simply giving adolescents more and more school experiences—those extra hours of after-school classes and homework—we could try to arrange more opportunities for apprenticeship. AmeriCorps, the federal community-service program for youth, is an excellent example, since it provides both challenging real-life experiences and a degree of protection and supervision.

“Take your child to work” could become a routine practice rather than a single-day annual event, and college students could spend more time watching and helping scientists and scholars at work rather than just listening to their lectures. Summer enrichment activities like camp and travel, now so common for children whose parents have means, might be usefully alternated with summer jobs, with real responsibilities.

Hmmm…maybe we professors should recruit teams of secretaries and teaching assistants from among our students, for their own good?