A recent study published in the journal Frontiers in Human Neuroscience suggests that babies who hear more than one language while in the womb may be more sensitive to a wider range of speech after they are born. While babies of monolingual mothers were found to be tuned into a specific pitch that corresponds with their mother’s language, babies of bilingual mothers were more sensitive to a variety of pitches and less tuned into a specific one. This implies that bilingual babies begin to learn about languages differently even before they are born.
Previous research has shown that babies learn about speech in the womb, with newborns preferring their mother’s voice and recognizing stories told to them while they were still in utero. However, there has been minimal research on how fetuses process speech if their mother is bilingual. The study, conducted at the University of Barcelona in Spain, involved 131 mothers and newborns, measuring their brain responses using electrodes on their foreheads to determine the frequency-following response (FFR). Results showed that monolingual babies were more sensitive to the specific pitch found in their mother’s language, while bilingual babies were more sensitive to a wider range of acoustic variations of speech.
The researchers found that exposure to monolingual or bilingual speech during pregnancy has different effects on the neural encoding of voice pitch and vowel sounds at birth. Newborns from bilingual mothers appear to be more sensitive to a wider range of acoustic variations in speech, while newborns from monolingual mothers seem to be more selectively tuned to the single language they were exposed to in the womb. This may represent a trade-off between selectivity and efficiency in how babies learn about pitch and speech.
The study emphasizes the importance of prenatal language exposure for the encoding of speech sounds at birth, but the researchers stress that the languages spoken while pregnant likely have minimal impact on how the baby learns about speech after birth. It is noted that the sensitive period for language acquisition lasts long after birth, and postnatal experiences may overshadow the initial changes that occurred in the womb. Future research into how a bilingual language environment affects sound encoding during the first years of life is needed to gain more insight into this issue. Parents need not worry about the impact of their speech on their children, as postnatal experiences are likely to have a greater influence on language acquisition.
