When your teenagers don’t seem to hear you, it’s not simply that they don’t want to clean their room or finish their homework: Their brains aren’t registering your voice the way they did in pre-teenage years.⁠ ⁠ Around age 13, kids’ brains no longer find their moms’ voices uniquely rewarding, and they tune into unfamiliar voices more, a new study from the Stanford School of Medicine has found.⁠ ⁠ _____⁠ ⁠ The research, published in April this year in the Journal of Neuroscience, used functional MRI scans to provide the first detailed neurobiological explanation for how teens begin to separate from their parents.⁠ ⁠ “Just as an infant knows to tune into her mother’s voice, an adolescent knows to tune into novel voices,” said lead study author Daniel Abrams, Ph.D., clinical associate professor of psychiatry and behavioral sciences. “As a teen, you don’t know you’re doing this. You’re just being you: You’ve got your friends and new companions, and you want to spend time with them. Your mi...