Infants are able to comprehend when a different language is spoken by watching the shapes and rhythm of the speaker’s mouth and face movements, revealed by researchers.
At four months, babies can tell whether a speaker has switched to a different language from visual cues alone, according to a University of British Columbia study, reported by researcher Whitney Weikum.
The findings suggest that older infants, raised in a monolingual environment, no longer need this facility. However, babies growing up in a bilingual environment advantageously maintain the discrimination abilities needed for separating and learning multiple languages.
The study is published in the journal Science.
Researcher Whitney Weikum explores whether babies use visual speech information to tell the difference between someone speaking their native language(s) and an unfamiliar language. Weikum is a UBC Neuroscience doctoral student working with Canada Research Chair and Psychology Prof. Janet Werker.
Their findings suggest that visual information alone will prompt the babies at four and six months to pay closer attention and watch the video for a longer period when the speakers switch languages.
“This suggests that by eight months, only babies learning more than one language need to maintain this ability. Babies who only hear and see one language don’t need this ability, and their sensitivity to visual language information from other languages declines.”
A similar approach is used in Baby Sign the practice of using sign language to communicate with infants and toddlers. According to proponents of Baby Sign, infants and toddlers have a desire to communicate their needs and wishes, but lack the ability to do so clearly because the production of speech, which requires coordinating the lips, tongue, breath, and vocal chords simultaneously, lags behind cognitive ability in the first months and years of life.