Changes in the brain may be the cause of teenagers 'being unable to hear their mother's voice'



It is unusual for a child who reacts immediately to his mother's voice when he was young to become less concerned about his mother's voice during adolescence and to argue, 'Why don't you listen to your mother?' is not. In fact, a study by Stanford University School of Medicine found that in the brains of children around the age of 13, 'the neural response when listening to the mother's voice changes, and the voice of others feels more valuable.' Reported by the team.

A neurodevelopmental shift in reward circuitry from mother's to nonfamilial voices in adolescence | Journal of Neuroscience

https://www.jneurosci.org/content/early/2022/04/06/JNEUROSCI.2018-21.2022

The teen brain tunes in less to Mom's voice, more to unfamiliar voices, study finds | News Center | Stanford Medicine
https://med.stanford.edu/news/all-news/2022/04/teenager-brain-mother-voice.html

New Study Reveals The Reason Teens Seem to Tune Out Their Mom's Voice
https://www.sciencealert.com/brain-signal-in-teenagers-shows-they-don-t-listen-to-their-parents-the-same-way

In a 2016 study , a research team led by Daniel Abrams of Stanford University School of Medicine conducted an experiment in which the brain of a child when hearing the voice of a mother or another person was photographed by magnetic resonance imaging (fMRI) . .. The research team asked the subjects 'voices of mothers speaking nonsense words' and 'voices of unknown women speaking nonsense words' to investigate whether the mothers' voices could be identified, and listened to the voices with fMRI. I took a picture of the inside of the brain while I was doing it, and investigated which part was activated.

As a result, the research team confirmed that 'there is a circuit in the brain of children under the age of 12 that is selectively activated by the mother's voice.' Children under the age of 12 identify their mother's voice with extremely high accuracy, and when they hear the mother's voice, not only the auditory processing area of the brain but also the reward center, emotion processing area, visual processing center, information processing area, etc. are activated. I did. On the other hand, the voice of an unknown woman did not activate any part other than the auditory processing area.

However, when the same experiment was performed on subjects aged 13 to 16.5, it was found that the brain activity of teenagers aged 13 and over was different from that of children under the age of 12. In the brain over the age of 13, the auditory processing area, information processing area, and area that creates social memory were activated for all voices, and only the mother's voice was not activated in a specific area. .. In addition, in the ventromedial prefrontal cortex, which determines the reward center and the value of information, it was more active against the voice of a stranger woman than the voice of the mother.

This means that the brain over the age of 13 becomes more sensitive and fascinated by the voices of strangers than the voices of mothers. Changes in brain activity occurred between the ages of 13 and 14, and there was no difference between men and women. The changes in brain activity with age were so significant that the research team reported that they were able to predict how old the subject would be by looking only at the response of fMRI to speech.



The researchers believe that changes that occur during adolescence are a sign that the brain is developing social skills and are a process of healthy maturity. For young children, the mother's voice plays an important role in health and development, affecting stress levels, social ties, feeding skills, and speech processing. However, as we approach the stage of acquiring broader social skills, it is advantageous for the brain to change and actively listen to voices other than the mother.

'In adolescence, you'll be able to tune in to new voices, just as infants can tune in to their mother's voice,' Abrams said. 'Teenagers won't realize they're doing that. They just live their own way, want to spend time with friends and new peers, and become more and more sensitive and drawn to unfamiliar voices. ' 'Children need to be self-reliant at some point, and the underlying biological signals need to facilitate this,' said Dr. Vinod Menon, co-author of the paper.

Previous studies

have also shown that children with autism have weaker brain activity for their mother's voice, so the results of this study also elucidate the neurobiological mechanisms underlying the development of social skills. It is expected to be useful for.



in Science, Posted by log1h_ik