Researchers at the University of Washington and Pacific Lutheran University in Tacoma report unborn babies are listening to their mothers talk during the last 10 weeks of pregnancy and at birth can demonstrate what they've heard.
That's because sensory and brain mechanisms for hearing have developed by 30 weeks of gestation, they said.
"The mother has first dibs on influencing the child's brain," Washington researcher Patricia Kuhl said. "The vowel sounds in her speech are the loudest units and the fetus locks onto them."
Although previous studies have show babies are born ready to learn and begin to discriminate between language sounds within the first months of life, the Washington study is the first evidence language learning had occurred in the womb.
"This is the first study that shows fetuses learn prenatally about the particular speech sounds of a mother's language," lead study author Christine Moon of Pacific Lutheran said. "This study moves the measurable result of experience with speech sounds from six months of age to before birth."