Babies can distinguish different languages (before they are even born)

Amazingly, babies can distinguish different languages while they are still in the womb.

A group of linguistic researchers from the University of Kansas Medical Centre in the US have used non-invasive technology to demonstrate that babies can distinguish different languages a month before they are even born. Their findings, published in the journal NeuroReport, showed that babies carried by American mothers-to-be can tell the difference between someone speaking to them in English and Japanese. Utako Minai, a professor of linguistics and team leader on the study, says the discovery has implications for foetal research in other fields:

"Research suggests that human language development may start really early - a few days after birth. Babies a few days old have been shown to be sensitive to the rhythmic differences between languages. Previous studies have demonstrated this by measuring changes in babies' behaviour; for example, by measuring whether babies change the rate of sucking on a pacifier when the speech changes from one language to a different language with different rhythmic properties."

Professor Minai had a bilingual speaker make two recordings, one in English and one in Japanese, to be played in succession to in-utero babies. According to linguists, English and Japanese are rhythmically distinctive languages. English speech has a dynamic rhythmic structure resembling Morse code signals, while Japanese has a more regular-paced rhythmic structure. Sure enough, the foetal heart rates changed when they heard the unfamiliar, rhythmically distinct language (Japanese) after having heard a passage of English speech, while their heart rates did not change when they were presented with a second passage of English instead of a passage in Japanese. Minai explains that babies in the womb hear speech sounds in a similar manner to the garbled speech of Charlie Brown's teacher:

"Foetuses can hear things, including speech, in the womb. It's muffled, like the adults talking in a Peanuts cartoon, but the rhythm of the language should be preserved and available for the foetus to hear, even though the speech is muffled."

Two dozen women, averaging roughly eight months pregnant, were examined using the heart sensing technology. Professor Kathleen Gustafson, from the Hoglund Brain Imaging Centre, was part of the investigation team:

"We have one of two dedicated foetal biomagnetometers in the United States. It fits over the maternal abdomen and detects tiny magnetic fields that surround electrical currents from the maternal and foetal bodies. The biomagnetometer is more sensitive than ultrasound to the beat-to-beat changes in heart rate. Obviously, the heart doesn't hear, so if the baby responds to the language change by altering heart rate, the response would be directed by the brain."

Gustafson says that the womb is a noisy environment, with a lot more going on than mums-to-be might assume:

"The foetal brain is developing rapidly and forming networks. The intrauterine environment is a noisy place. The foetus is exposed to maternal gut sounds, her heartbeats and voice, as well as external sounds. Without exposure to sound, the auditory cortex wouldn't get enough stimulation to develop properly. This study gives evidence that some of that development is linked to language."