The Art Of Conversation

Talking To Babies Might Boost Their Brain Growth

A new study finds that babies who are exposed to more speech grow more of an important brain structure.

A dad talks to his baby, who lies on a bed, while his older daughter kisses the baby.
Marko Geber/Getty

Most parents have been told that verbal communication with infants and toddlers can improve developmental outcomes. However, new research shows that talking to your toddler might be more critical than previously thought.

According to a new study published in the Journal of Neuroscience, the brains of toddlers whose parents talk to them frequently are structurally different from those whose parents aren’t as chatty. A research team from the University of East Anglia in the UK used wearable recording devices to measure the amount of speech that 87 6-month-olds and 76 30-month-olds were exposed to in their home environments — for a total of more than 6,000 hours of recorded speech. The babies were then given MRI scans while asleep.

The team found that in the 30-month-old group, children who were exposed to more speech had significantly more myelin present in their brains. Myelin is a structure that develops around nerves and helps transmit signals more efficiently from nerve to nerve. The more myelin present, the more quickly and easily signals can move through the brain.

“Imagine you have a hosepipe with lots of holes in it,” lead study author John Spencer of the University of East Anglia told Independent. “Myelin is like wrapping the hosepipe with duct tape – it insulates neural fibres, bringing more of the ‘signal’ from one brain area to the next.”

In the 6-month-old group, the team surprisingly found less myelin in infants who were exposed to more adult speech. Though unexpected, the results might be easily explained by their developmental phase. “When you’re six months old more input is good. But at that point, your brain is growing massively and you get this massive growth of new neurons,” Spencer told The Guardian. “So the input comes in and may help prolong that period of brain growth.”

By the time the child is 30-months-old, the brain is in a different growth stage. “Now, it’s starting to prune back some of the cell growth, form specific connections, and that’s where myelin comes in. So now the input starts to help structure the myelin,” Spencer said.

These newest findings are similar to previous research that has shown the importance of verbal communication in infants and young children. But other research has found that not just any talk will do. Using adult speech patterns and engaging in back-and-forth communication, not baby talk, is more effective in helping infants and toddlers develop early communication skills.

The new study also confirms previous findings that children from higher-income families and with more highly educated mothers experience more communication at younger ages than those from different socioeconomic backgrounds.

The study is, however, limited by a small sample size, and more research is necessary to determine if these results are repeatable across population demographics and if the structural changes persist as the child ages.

“I think the take-home message is, absolutely talk to your kids,” Spencer said. “What’s pretty striking here is that it’s literally shaping the structure of the brain.”