
Among preterm newborns, greater exposure to the mother’s voice after birth appeared to speed up the maturation of a key language-related brain circuit, in a small clinical trial conducted by investigators at Weill Cornell Medicine, Burke Neurological Institute and Stanford Medicine. The finding provides direct experimental support for the idea that a mother’s voice promotes her child’s early language-related brain development. It also hints that boosting exposure to maternal speech might ameliorate the language development delays often seen among children born prematurely.
The study, published Oct. 14 in Frontiers in Human Neuroscience, included 46 preterm infants who were born at just 24 to 31 weeks gestational age. Half received routine exposure to the mother’s voice, while the other half had routine exposure augmented with multiple daily audio recordings of the mother’s voice. Later MRI scans of the infants’ brains suggested significantly greater maturation in the left arcuate fasciculus, a brain circuit known to be involved in speech and language processing.

Dr. Katie Travis
“This preliminary study adds to evidence that hearing mother’s voice is very important for infants at this stage of life—and might even be key to reducing language delays among preemies,” said first author Dr. Katie Travis, who was an assistant professor at Stanford Medicine when the study was conducted there and is now an assistant professor of neuroscience in pediatrics at Weill Cornell Medicine and director of the Laboratory for Language Development and Recovery at Burke Neurological Institute.
Prior associational studies have linked exposure to the mother’s voice to the healthy development of auditory and language-related brain areas in older infants and toddlers. With their clinical trial design, Dr. Travis and her colleagues sought to demonstrate conclusively that one causes the other.
Conducting the study among preterm infants in a hospital nursery, where exposure to maternal speech is much less than in the womb, allowed the researchers close experimental control of such exposures. Twice per hour between 10pm and 6am, the 23 infants in the “treatment” group heard ten-minute audio recordings of their mothers reading a children’s story—giving them 160 minutes of extra exposure per day until hospital discharge.
For their outcome measure, the researchers examined the arcuate fasciculus, a bundle of nerve fibers that connects language areas in the brain and is particularly prominent in the brain’s left hemisphere. Using MRI to scan the infants around the time they would have reached full term, the researchers found signs of significantly greater maturation in the left arcuate fasciculus in the treatment group compared to the control group.
Dr. Travis and colleagues now plan to do larger multi-studies of this kind at both Weill Cornell and Stanford Medicine and will examine whether increased exposure to the mother’s voice in premature infants can help prevent language delays. The investigators aim to include babies with varying medical complications to make sure the treatment generalizes to them as well.
The research was supported by the Eunice Kennedy Shriver National Institute of Child Health and Human Development, part of the National Institutes of Health, through grant numbers 5R00-HD84749 and 2R01-HD069150.