Teen Brain Scans: A rebirth of Phrenology?

[SoulRiser]

Quote:Matthew Yglesias brings up an article in the Washington Post yesterday that cites a new study that 'proves' the inferiority of teenage, and indeed early 20-year-old's brains. Apparently I am a danger to myself and others around me because of my propensity for reckless risk taking. While Yglesias shrugged it off, I think it deserves a far closer look.

Quote: A National Institutes of Health study suggests that the region of the brain that inhibits risky behavior is not fully formed until age 25, a finding with implications for a host of policies, including the nation's driving laws.

Largely this finding is reached through taking MRI scans of the brain, and relying on purely physical evidence to determine and predict behavior. I am entirely skeptical, and even the author of the study, Jay Giedd, said there is no proven correlation between brain imaging and behavior. This, it seems, is another junk science attempt to prove the inferiority of teenagers based on shaky scientific evidence and politically motivated hypothesis', not unlike the many scientific studies released a century ago that 'proved' the less developed and thus inferior brains of women and blacks.

Jean Piaget, the Swiss psychologist who was one of the most eminent scientists in the history of psychology studied the issue as well. Piaget is responsible for much of the understanding about young children that gets taken for granted. His research though didn't stop with toddlers, yet since his conclusions no longer match our norms and expectations for teenagers they don't come up as much as brain scans like above.

Piaget found in his research that young people develop adult levels of reason and judgment at around 14-15, and many get there at 11 or 12. Furthermore he found that if someone doesn't achieve "formal operational thinking" by age 15 or so, they probably never will. Many adults never do. In several experiments done in the 70's it was found that not only do many adults lack formal operational thinking, but this ability tends to decline over time with adults in their 50s and 60s scoring lower than those in their early 20s.

Another standard, moral reasoning, put forward by the American psychologist Lawrence Kohlberg, found that by age 11 or so, many people achieve "conventional" reasoning, i.e. a level of reasoning ability that is standard and normal for adults of all ages. Other studies by David Wechsler and later J.C. Raven, done in the 1940s, suggest intelligence peaks around 14-15.

All of these studies are done on direct, behavioral and cognitive tests. NOT simple brain scans, which have little, if any, relevance to actual behavior.

The reliance on physical evidence such as brain scans seems much like a more advanced form of phrenology and craniometry which were used a century ago to prove the superiority of the 'white race'. There have been a multitude of studies out recently claiming teens are more guided by their emotions, or lazier, or more risk-prone than adults. Often these studies are done poorly, or their results are wildly mischaracterized and misused in the pursuit of magazine sales, TV viewers, and accomplishing legislative goals. Instead of writing a book refuting these studies (its already been written, and will be coming out in the next few months by Dr. Robert Epstein, from which I'm getting much of my research) I will just make one basic point: Correlation does not imply causation.

In other words, Elliot Valenstein wrote that:

Quote: A person's mental state and experience can modify the brain just as surely as the other way around. When there is a correlation between two events, we should not assume that we always know which way causation flows.

Assuming we trust the results of Giedd's brain scans, we must question, as he does, the rush to assign causality. Does a malformed or immature teenage brain affect behavior? Or does one's experiences and environment affect their brain? While not wanting to rehash the old nature vs. nurture debate, as this post is entirely long enough already, I'd just like to briefly address the state of being a teenager in America.

Teens today are subjected to more restrictions, more disrespect, more penalties and frustrations than any other group in society. Simple liberties such as leaving the house at night, or choosing what food to eat and when, are regularly denied teens. Simple privacies like having a bedroom door and trusting the security and privacy of one's own person are often denied teens. In a multitude of ways teens live as an oppressed, second-class citizenry. Would it surprise anyone that this state of affairs would have an affect on teen behavior, or even their brains?

You cannot study black slaves and make pronouncements regarding an entire race of people. Likewise you cannot study oppressed teens and expect results that would remain accurate for empowered, free teens.

Considering the fever with which these studies get latched onto, and the connection between them and calls to raise age restrictions, I wouldn't be surprised at all to see proposals to raise the drinking age or driving age to 25. Unlike Yglesias, I think all of us should have a strong concern when some study makes the case for our inferiority. Especially when it resembles now discredited racial science of a century ago.

found: http://www.oneandfour.org/archives/2005/..._scan.html

washington post article