Kids are known as little language geniuses. Even infants just a few months old can distinguish language sounds. But new research proves that babies are boning up on language even in the weeks before birth. Researcher Christine Moon of Pacific Lutheran University in Tacoma, Washington and her team speculate that such activity could begin as early as 30 weeks after conception.
By analyzing the way newly born infants suck on their pacifiers, scientists have been able to prove that fetuses are listening to their mothers talk during the last 10 weeks of pregnancy and at birth can demonstrate what they’ve heard.
Forty infants, each just 30 hours old, were studied in Tacoma and in Stockholm, Sweden. Their interest in language sounds was measured by how long each infant sucked on a pacifier. When introduced to unfamiliar sounds, such as those spoken in another language, infants sucked longer. They sucked more briefly when they heard familiar sounds.
Since researchers only used brand-new babies for the study, the research demonstrates that infants are differentiating between unfamiliar sounds and the sounds that they had been hearing in utero for 10 weeks inside their mothers.
The study tested newborns on both Swedish and English vowel sounds. The researchers tested the babies’ interest in the vowel sounds based on how long and how often they sucked on a pacifier. Half of the infants heard their native language vowels, and the other half heard the foreign vowels.
The pacifier was rigged to play one vowel sound per suck until the infant stopped sucking, and then play the next vowel sound when the baby resumed sucking.
In both countries, the babies listening to the foreign vowels sucked more than those listening to their native tongue. This indicated to researchers that they were learning the vowel sounds in utero. Babies are hearing very early on, and on some level are responding to the voices they hear while still in the womb.
“This is the first study that shows fetuses learn prenatally about the particular speech sounds of a mother’s language. This study moves the measurable result of experience with speech sounds from six months of age to before birth,” says Moon.
Prior to the study, the scientific consensus was that infants learned their vowels and consonant sounds after birth.
“The mother has first dibs on influencing the child’s brain,” says Patricia Kuhl, co-author and co-director of the Institute for Learning & Brain Sciences at the University of Washington. “The vowel sounds in her speech are the loudest units and the fetus locks onto them.”
Multilingual moms are probably wondering what sort of vowel sound signals they are putting out for their kids, and if mixed signals make any difference. Further research is required.