TUESDAY, May 16, 2023 (HealthDay News) -- When parents talk to their toddlers, they are not only teaching them words, but may be shaping their developing brains, too, a new study suggests.
Researchers found that toddlers whose parents spent a lot of time talking to them day to day showed a particular brain characteristic: a greater concentration of myelin in language-related parts of the brain.
Myelin is a protective layer of protein and fat that wraps around nerve fibers in the brain, helping to speed the transmission of electrical signals through them.
The new findings suggest that when toddlers are exposed to more chat, their brains accumulate myelin more rapidly than youngsters who hear fewer words.
"Myelination of the brain is really important, as it makes communication between brain cells more efficient. This, in turn, can help speed up thinking," said senior researcher John Spencer, a professor of psychology at the University of East Anglia in England.
It's unclear whether toddlers with relatively more myelin in language areas of the brain ultimately develop stronger language skills. But Spencer said his team is following the same children over time, so the answer to that question may be coming.
For now, he said, the message for parents is simple: "Talk, talk, talk to your children."
That goes for infants, too, according to Spencer. Even though they may not know language yet, he said, "they are listening, and your input literally helps shape their brains."
The study, published May 15 in the Journal of Neuroscience, involved 163 babies and toddlers who were around the ages of 6 months and 30 months, respectively. All wore small recording devices for up to 16 hours a day, for three days, to capture the amount of adult chatter they were hearing.
That could have included parents and other caregivers talking to them, reading to them, or simply talking to someone else nearby.
The researchers then used MRI scans to quantify the amount of myelin in specific language-related areas of the youngsters' brains.
Among the toddlers, the study found, there was a direct correlation between the amount of adult talking they heard and the concentration of myelin in their brains. That was not the case, however, for the 6-month-olds: Babies surrounded by more chatter showed less myelination versus other infants.
The reason is not clear. But Spencer speculated on a possible explanation: A 6-month-old's brain, he said, is primarily concerned with growing more cells, whereas myelination is "ramping up" in the toddler brain.
It's possible, Spencer said, that parents' words help support whatever their child's brain needs the most at that point: cell growth in infancy and myelination in toddlerhood.
Anand Patel is a child psychologist at Montefiore Medical Center in New York City. He said it makes sense that a young child's "interactions with the world" could create physiological change in the brain.
Oftentimes, Patel said, parents' talk time with their babies and toddlers is seen as a way to bond emotionally -- which it is, he noted.
But as this study demonstrates, it may also be a critical contributor to their brain development, said Patel, who was not involved in the research.
Talking to your little one does not have to mean a formal "learn this word" lesson. In fact, Patel said, teaching language "indirectly" -- just by talking -- is a better approach.
That can include talking "serve-and-return" style with a toddler, or singing a song or reading a book aloud. Parents can also talk "broadcaster" style, Patel said. When they're making dinner, for instance, they can narrate what they're doing to their child sitting in the high chair.
That, Patel said, is a helpful point for busy parents. They can fit talk time in while they're going about their daily tasks.
Since we live in the era of devices, the findings do bring up the question: Can hearing any talking, from a parent in the room or a voice on a smart pad, boost young children's brain development?
The study did not address that. But Patel said he believes that while limited amounts of device time may be OK, "nothing can replace the human interaction."
"Given that we're in this electronic age," Patel said, "I think a study like this emphasizes the importance of parent-child interactions -- not only for their emotional and mental well-being, but for their brain development as well."
The American Academy of Pediatrics has resources on early childhood development.
SOURCES: John P. Spencer, PhD, professor, School of Psychology, University of East Anglia, Norwich, U.K.; Anand V. Patel, PsyD, child psychologist, Pediatric Behavioral Health Integration Program, Montefiore Medical Center, New York City; Journal of Neuroscience, May 15, 2023, online