"Inventing Ourselves" (Courtesy of PublicAffairs)

Teenagers! They chew Tide Pods and have unprotected sex. They use social media we haven’t even heard of and are walking hormone machines. It’s easy to mock their outsize sense of self and their seemingly dumb decisions. But not so fast, says cognitive neuroscientist Sarah-Jayne Blakemore: The adolescent brain is nothing to laugh at.

In “Inventing Ourselves: The Secret Life of the Teenage Brain,” Blake­more (no relation to the writer of this article) challenges adults to take teenagers and their growing brains seriously. Her book explains what’s happening inside those brains during the teen years — a complex period of neurological change that is fundamental to maturity.

Blakemore breaks down the most up-to-date science on adolescent brain development. It turns out that much of what makes teenagers seem so, well, teenage is due not to their hormones but to their rapidly changing brain circuitry. The malleable mind continues to develop during adolescence, consolidating personality, preferences and behaviors.

Some of those behaviors, including risk-taking and a tendency toward self-consciousness, may seem connected to peer pressure. But, Blakemore writes, they’re actually signs of brain development. With the help of data from studies that show the teenage brain in action, she connects brain development to all sorts of things, including self-control and depression.

There’s still a lot to learn about adolescent brains, and scientists don’t fully understand how things such as genetics affect brain development. But what we do know, Blakemore says, can help adults become more compassionate toward teenagers and can point to educational and social policies that work with adolescent brains, not against them.

“The adolescent brain isn’t a dysfunctional or a defective adult brain,” she writes; it’s “a lens through which we can begin to see ourselves anew.” Blakemore paints the teenage brain as tempestuous, impressionable, dynamic — and well worth studying.