April 2011
March 2011
Is it sheer stupidity that makes teenagers take excessive risks? Neuroscience proposes that teen brains actually suffer from underdeveloped cognitive-control functions that are out of sync with fast developing neural reward-systems.
Teenagers are a puzzle, and not just to their parents. When kids pass from childhood to adolescence their mortality rate doubles, despite the fact that teenagers are stronger and faster than children as well as more resistant to disease. Parents and scientists alike abound with explanations. It is tempting to put it down to plain stupidity: Teenagers have not yet learned how to make good choices. But that is simply not true. Psychologists have found that teenagers are about as adept as adults at recognizing the risks of dangerous behavior. Something else is at work.
Scientists are finally figuring out what that “something” is. Our brains have networks of neurons that weigh the costs and benefits of potential actions. Together these networks calculate how valuable things are and how far we’ll go to get them, making judgments in hundredths of a second, far from our conscious awareness. Recent research reveals that teen brains go awry because they weigh those consequences in peculiar ways.
In teenagers only, the sight of a happy face triggered a significant response from the ventral striatum, a small patch of neurons located near the center of the brain. The ventral striatum is especially sensitive to dopamine, which produces a feeling of anticipation and helps the brain focus on reaching a goal. The ventral striatum produces bigger responses to bigger rewards, and in teens it is rigged up to an amplifier, making rewards seem more appealing still.
A separate network of regions in the front of the brain is responsible for evaluating conflicting impulses. This cognitive control network allows us to hold back an action that could deliver a short-term reward if it interferes with a long-term goal. The network grows very slowly over the first 25 years of life. As a result, it works poorly in childhood, better in teens, and even better in adults.
Neuroscientist B. J. Casey and her colleagues at the Sackler Institute of the Weill Cornell Medical College believe the unique way adolescents place value on things can be explained by a biological oddity. Within our reward circuitry we have two separate systems, one for calculating the value of rewards and another for assessing the risks involved in getting them. And they don’t always work together very well.
Casey was able to watch the cognitive control network in action. She and her colleagues analyzed the brain scans of volunteers while they kept themselves from hitting a key that they weren’t supposed to hit. At those moments, part of the cognitive control network, called the inferior frontal gyrus, was more active than it was at other times. When the scientists compared the cognitive control network response in people of different ages, they found a striking pattern. In children the network was the most active, in teenagers the activity was lower, and in adults it was lower still. Casey proposes that as the cognitive control network matures, it gets more efficient. The upshot is that as we age, we need to put less effort into holding ourselves back.
The trouble with teens, Casey suspects, is that they fall into a neurological gap. The rush of hormones at puberty helps drive the reward-system network toward maturity, but those hormones do nothing to speed up the cognitive control network. Instead, cognitive control slowly matures through childhood, adolescence, and into early adulthood. Until it catches up, teenagers are stuck with strong responses to rewards without much of a compensating response to the associated risks.
From an evolutionary point of view, the daredevil impulses of adolescents can be beneficial, Casey points out. Once a young mammal becomes sexually mature, it needs to leave its parents and strike out on its own. It must find its own supply of food and establish its place in the world of adults. In some mammal species, adolescence is a time for individuals to leave one group and find a new one. In others, it is a time to seek out sexual partners.
The reward system of the teenage brain may make adolescents more willing to face the risks that come with this daunting new stage of life. But with access to modern dangers like illegal drugs and fast cars, the human risks have increased. Evolution does not operate quickly enough to have reacted to such factors.
The brain’s heightened responses can also open the way for psychological troubles. Due to experience, environment, or genes, some teens may possess relatively low levels of cognitive control, making them particularly vulnerable to neurological signals of fear, Casey suggests. If the signals go unchecked, they may lead to anxiety, depression, or other disorders such as addiction. And even well-adjusted adolescents may be primed to choose the heart over the head—or, perhaps we should now say, the ventral striatum over the inferior frontal gyrus.
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I don’t buy that art has an expiration date, and I can prove it. I ate week-old chili yesterday and look at me now. The problem with pop culture references in sitcoms isn’t that they become dated when future consumers (THINK OF THE CHILDREN!) are so far removed from the era of reference and, less saliently, so confounded by the contemporary worship of hollow, self-serious pretension as greatness that they can’t recall what the War on Terror was in general or the invasion of Iraq in specific, much less Michael Moore, Mission Accomplished, free speech zones, Peanuts, or the Soup Nazi, so they watch Arrested Development with stony-faced revulsion at the America which once embraced and glorified incest, embarrassed that their great-grandparents actually thought this American Oedipus (and then some) was funny. That’s on them, and stepping in on their behalf is the most feckless of concern trolling. When has not understanding something ever given one license to denounce it? I’m not going to ask my grandma her opinion on Islam. I can turn on Glenn Beck for myself, thankyouverymuch.
Whether a sitcom leans more on creative slapstick or witty wordplay or even, Oprah help us, pop culture references, durability comes from greatness—that is, the artful expression of meaning, depth, purpose, thesis if you wanna get all Aristotelian about it, Mr. Fancy Pants College Degree—not whether a show incorporates topical humor or not. You don’t need to have endured the hype for The English Patient—or even know that it’s a real movie—to identify with Elaine seeing through the emperor’s new clothes. You don’t need to scour Gawker and Mediaite to catch the fluid media satire of 30 Rock. The only Burt Reynolds movie I’ve ever seen is Boogie Nights, but Archer still makes me laugh more than any other show on TV. Reference humor is just one paintbrush, and it can shade character, comment, or overwhelm.
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Blitzen Trapper - Furr