"Everybody knew something wasn't right with her. She would flirt with all the boys on the football team, she would favor them. She would be rude to all the girls."
My local Target was the first place I noticed the shift. One day, a few years ago, a sign appeared: red text on white paper announcing that no one under 18 would be allowed in without an adult. Before the poster, every weekday afternoon, clots of teens would move through the arteries of the store, occasionally blocking them. The kids would laugh among themselves, swatch makeup on their arms, peruse the candy offerings.
Adolescence is second only to early childhood in the rapidity and sheer volume of changes occurring in brain development. Three different brain systems (and their interconnections) are at play: reward-driven behavior, harm avoidance, and regulatory behavior. At the same time, teens are experiencing powerful changes to their physical and sexual selves, accompanied by the hormonal cascade of puberty. During this period, there is an increase in brain receptors for dopamine, a neurotransmitter that has a strong effect on the experience of pleasure.