In a comments thread, shorelines linked to a fascinating Scientific American article about adolescence by psychologist Robert Epstein. In it, he points to the invention of the very idea of adolescence and its non-universality. In a sample of 186 pre-industrial societies, for example, only 60% had words for the life stage and most had little or no problems with anti-social teen behavior. This data, however, contrasts strongly with new research suggesting that adolescent brains are quite different from adult brains.

How do we make sense of this?

Epstein suggests that differences in brain structure may be the result of social realities, not their cause. He writes:

I have not been able to find even a single study that establishes a causal relation between the properties of the brain being examined and the problems we see in teens… [Meanwhile, c]onsiderable research shows that a person’s emotions and behavior continuously change brain anatomy and physiology… So if teens are in turmoil, we will necessarily ﬁnd some corresponding chemical, electrical or anatomical properties in the brain. But did the brain cause the turmoil, or did the turmoil alter the brain? Or did some other factors—such as the way our culture treats its teens—cause both the turmoil and the corresponding brain properties.

By “the way our culture treats its teens,” Epstein is referring to the possibility that we infantilize and criminalize them. He includes a figure illustrating how we’ve increasingly targeted teens with laws:

Teens are subject to, Epstein explains, “…more than 10 times as many restrictions as are mainstream adults, twice as many restrictions as active-duty U.S. Marines, and even twice as many restrictions as incarcerated felons.”

Believing them to be different from adults, we then segregate them:

Today, with teens trapped in the frivolous world of peer culture, they learn virtually everything they know from one another rather than from the people they are about to become. Isolated from adults and wrongly treated like children, it is no wonder that some teens behave, by adult standards, recklessly or irresponsibly.

Epstein has no more data showing that how we treat teens, and how they learn to behave, changes their brain anatomy and physiology, than he does showing the reverse. But the former certainly has substantial neurological precedent. Meanwhile, the latter is comforting to a society awash in out-of-control adolescence: “What is there to do? It’s only natural.” Right?