In Untangled: Guiding Teenage Girls Through the Seven Transitions into Adulthood (Ballantine, Feb.), psychologist Damour examines sources of stress and anxiety for this age group.

How is life different for teenage girls now compared to when their parents were that age?

The game-changing difference between our adolescence and our children’s is that we did not come of age swimming in digital waters. On one hand, social media can strengthen positive relationships and connect young people who, in the past, might have felt marginalized or isolated. On the other hand, it can be a tremendous source of stress—even when teenagers are getting along well with their peers—because it does not allow them to take much-needed breaks from being connected to nearly everyone they know. Further, technology is the enemy of sleep for many teens, and sleep is vital. It’s the glue that holds every one of us together.

What’s the most common problem you encounter when counseling girls? Is there anything parents can do at home to combat that issue?

More than anything, girls talk to me about how stressed and anxious they feel—which is why I decided to write Under Pressure. The good news is that there is a great deal that parents and adults at school can do to help. First, we can teach girls that stress and anxiety are normal and healthy functions and nothing to be afraid of. Until we do that, we will be raising a generation of young people who become unduly stressed about being stressed and anxious about being anxious. From there, we can help girls develop adaptive strategies for coping with the predictable and unavoidable stresses and tensions that will come their way, such as those that arise in their interactions at home, with other girls, with boys, at school, and in their dealings with the broader culture.

I liked what you had to say about friendships among young girls and how they are, more often than not, a source of support. Why do you suppose stereotypes about “mean girls” are so prevalent?

The widespread use of the term “mean girls” may contribute to the sense that girls are unusually mean. Statistically, this isn’t true. Boys are far more physically aggressive and, in some studies, have been found to use just as much social aggression. Interestingly, when girls feel hurt by a social situation, they are more likely than boys to look to their friends and adults for support, and their female friends are more likely than boys to take on what we call “vicarious stress”—to become upset on their friend’s behalf. In other words, adults may be more likely to hear about it when a girl finds herself on the sharp end of a social stick—but that doesn’t mean girls are meaner than boys.