Mothers who play “Beethoven for Babies” may have the right idea, though new research shows those that play books on tape or read to their fetuses are helping their progeny even more. Hours-old newborns can differentiate between sounds from their native language and foreign languages, implying that babies begin absorbing language while still in the womb.
Hearing begins developing at around 30 weeks into gestation. The new study suggests that babies are listening to their mothers talk during the last 10 weeks of pregnancy and can even demonstrate what they’ve heard. Previous studies showed that newborns begin learning and discriminating between language sounds within the first months of life, but the researchers think this study is the first to show that language learning begins occurring in utero.
To show this, the research team exposed 40 30-hour-old infants in Sweden and Washington to vowel sounds in their native tongue and in foreign languages. (These are the loudest units in speech.) The researchers measured the infants’ interest in the different sounds by how long they sucked on a pacifier that was wired to a computer. Longer sucking indicates that infants are learning while shorter sucking indicates that they are already familiar with a sound. In both the U.S. and Sweden, the babies sucked longer on their pacifiers when foreign languages played than they did for their native tongue.
Of course, some tiger moms may not be satisfied knowing that their baby is getting a hand up on its native tongue even before it enters the world. Rosetta Stone foreign language tapes for babies may soon usurp Beethoven as the womb soundtrack of choice.
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