Parents who talk more to their infants improve their babies’ brain development, according to new research.
A team led by a University of Texas at Dallas neurodevelopment researcher is behind the study, which is among the most conclusive evidence showing a link between caregiver speech and an improvement in infant brain development. The study was published in the June edition of Developmental Cognitive Neuroscience.
Specifically, exposure to more words demonstrated a positive impact on long-term language progress in infants.
The research monitored babies at several stages; home language recordings were collected when the subjects were 9 months old and then again six months later, and MRIs were performed at 3 months and 6 months old, and at ages 1 and 2.
“This timing of home recordings was chosen because it straddles the emergence of words,” corresponding author of the study and assistant professor of psychology Meghan Swanson said in a statement. “We wanted to capture both this prelinguistic, babbling time frame, as well as a point after or near the emergence of talking.”
The study explored how the brain’s white matter develops in connection with caregiver speech. White matter in the brain is what facilitates communication between gray matter regions, which is where information processing takes place in the brain, explained a study breakdown via the University of Texas at Dallas.
The team, headed by Swanson, imaged several areas of white matter in baby brains, focusing on developing neurological pathways.
Infants who had heard more words showed signs that the structure of their white matter was slower to develop. This was evident by lower fractional anisotropy (FA) values, which is the metric for the freedom or restriction of water movement in the brain. FA values are used as a proxy for the progress of white matter development.
When the infants showing lower FA values — and thus slower developing white matter — after exposure to more words began to speak, they had better linguistic performance.
“As a brain matures, it becomes less plastic — networks get set in place. But from a neurobiological standpoint, infancy is unlike any other time. An infant brain seems to rely on a prolonged period of plasticity to learn certain skills,” Swanson said. “The results show a clear, striking negative association between FA and child vocalization.”
Co-first author of the paper Sharnya Govindaraj said at first researchers were surprised with the results.
“We initially didn’t know how to interpret these negative associations that seemed very counterintuitive. The whole concept of neuroplasticity and absorbing new knowledge had to fall into place,” Govindaraj said in a statement. “Which ability we’re looking at also matters a great deal, because something like vision matures much earlier than language.”
Swanson herself is a mother and said she was curious of the impact on her toddler, who is raised in a household using two languages.
“Raising a bilingual child, it is remarkable how she is not confused by languages, and she knows who she can use which language with,” she said.
Swanson said the key takeaway is that parents have the power to help their children develop.