Oh, that pesky, underdeveloped prefrontal cortex. It causes so many problems. Including anxiety. You thought that the SATs were stressing out your kid? Nope. Blame the amygdala.

Different regions and circuits of the brain mature at very different rates. It turns out that the brain circuit for processing fear — the amygdala — is precocious and develops way ahead of the prefrontal cortex, the seat of reasoning and executive control. This means that adolescents have a brain that is wired with an enhanced capacity for fear and anxiety, but is relatively underdeveloped when it comes to calm reasoning.