Infants' social skills play a key role in helping them learn a foreign language, a new study has found.
Researchers at the Institute for Learning & Brain Sciences (I-LABS) at the University of Washington have shown for the first time that early social behaviour called gaze shifting is linked to infants' ability to learn new language sounds.
Babies about 10 months old who engaged in more gaze shifting during sessions with a foreign language tutor showed a boost in a brain response that indicates language learning.
"Our study provides evidence that infants' social skills play a role in cracking the code of the new language," said co-author Patricia Kuhl, co-director of I-LABS.
"We found that the degree to which infants visually tracked the tutors and the toys they held was linked to brain measures of infant learning, showing that social behaviours give helpful information to babies in a complex natural language learning situation," said Kuhl.
Gaze shifting, when a baby makes eye contact and then looks at the same object that the other person is looking at, is one of the earliest social skills that babies show.
"These moments of shared visual attention develop as babies interact with their parents, and they change the baby's brain," said co-author Rechele Brooks, research assistant professor at I-LABS.
For the study, 9.5-month-old babies from English-speaking households attended foreign language tutoring sessions.
Over four weeks, the 17 infants interacted with a tutor during a dozen 25-minute sessions. The tutors read books and talked and played with toys while speaking in Spanish.
At the beginning and end of the four-week period, researchers counted how often the infants shifted their eye gaze between the tutor and the toys the tutor showed the baby.
After the tutoring sessions ended, the researchers measured the infants' brain responses to English and Spanish sounds, to see how much Spanish the babies had learnt.
The babies listened to a series of language sounds while wearing an electroencephalography (EEG) cap to measure their brain activity.
The results showed that the more gaze shifting the babies participated in during their tutoring sessions, the greater their brain responses were to the Spanish language sounds.
"Our findings show that young babies' social engagement contributes to their own language learning - they're not just passive listeners of language," Brooks said.
"They're paying attention, and showing parents they're ready to learn when they're looking back and forth. That's when the most learning happens," Brooks said.
The study was published in the journal Developmental Neuropsychology.