Science writer Michaeleen Doucleff was sitting on a beautiful beach with her daughter, but she couldn’t relax. She kept reaching for her phone, checking it over and over. She was frustrated but couldn’t stop. Why was she doing this? In her new book, “Dopamine Kids: A Science-Based Plan to Rewire Your Child's Brain and Take Back Your Family in the Age of Screens and Ultraprocessed Foods,” Doucleff explores how devices can hijack our brain’s reward system to keep us coming back for more, even after the pleasure is gone.