A new study, published April 28 in the Journal of Neuroscience, shows that around the age of 13, a teen's brain's vocal preferences shift, tuning mother's voices out in favor of unfamiliar ones. The findings offer an actual "brain basis" for kids' behavior changes, stated lead researcher Daniel Abrams. "Most parents can tell you how their teenagers begin to focus their attention on peers and new social partners," said Abrams, a clinical associate professor of psychiatry and behavioral sciences at Stanford University School of Medicine, in California. [tweet_embed] May 3, 2022[/tweet_embed] "What's new here is this understanding of what's happening in the brain," he exclaimed. While it may seem like your teenager is tuning you out, Abrams promised, "it's not personal. This is a natural part of development." The findings build on a 2016 study by the Stanford team showing that, unlike strangers' voices, the sound of a mom's voice "lights up" reward centers in a younger child's brain. Abrams explained this makes sense as parents are the center of a child's world — their primary source of learning, which includes social and emotional development. However, at a certain point, kids must expand their social world, getting ready for independence and eventually starting their own family in many cases. [tweet_embed] May 3, 2022[/tweet_embed] Enter the new study, which included 46 kids, aged 7 to 16, who underwent functional MRI scans. This allowed the researchers to view their brain activity while they listened to recordings of either their own mother's voice or unfamiliar female voices. It turned out that teenagers were evidently distinct from younger kids. Their brain reward centers lit up more in response to the unknown voices versus mom's — as did a brain region called the ventromedial prefrontal cortex, which places value on social information. [tweet_embed] May 3, 2022[/tweet_embed] So do those brain changes happen first, or does the brain adapt in response to kids' growing social circles as they get older? It's likely the brain is "programmed" to make the evolution, whether those brain changes happen first, or the brain adapts in response to kids' growing social circles as they get older, said Moriah Thomason, an associate professor of child and adolescent psychiatry at NYU Langone Health, in New York City. "Adolescence is a time when we prepare to leave the nest and become adults," said Thomason, who was not involved in the research. "If there weren't some amount of biological programming, that would be maladaptive." Like Abrams, she highlighted how the findings offer an understanding of the brain basis for an aspect of teen behavior that's well known to parents. "This might help parents contextualize it," Thomason suggested. "This is a natural part of maturation." Abrams agreed that changes in the brain's voice preferences likely come first. That would be in line with evidence of broader shifts in the teenage brain's reward system, where it becomes more responsive to things such as novelty and risk-taking. The study also found that in various other ways, teenagers' brains became more responsive to all voices, including moms, compared with younger kids. for example, brain areas involved in filtering information and creating "social" memories became more active the older a teenager was. Thomason speculated that might all reflect the necessity to develop more sophisticated ways of understanding and interpreting verbal communication as people move from childhood to adulthood. To Abrams, the study also underscores the broader importance of voice to human beings. "Voices are among the most important social signals we have," he expressed. "They connect us, and help us feel we're part of a community. And I would argue that hearing a loved one's voice is one of the most rewarding experiences we have in our daily lives."