As we explored last week, foreign language development declines rapidly after the first year of infancy.
This is when mind-mapping of language is set, and recognition of foreign sounds becomes “interference.”
But before a year, an infant’s mind can map foreign languages in a way that can help them identify foreign sounds.
In an experimental demonstration of phonetic learning, University of Washington neuroscientist Patricia Kuhl has found that American infants exposed to Mandarin Chinese were able to differentiate between its phonetic elements, but only through social interaction with a human.
The Experiment: “Chee” and “She”
A pair of studies tested whether infants could distinguish between the two.
In the initial study and the first experiment of its kind, 9-month-old American infants were exposed to Mandarin for less than five hours in a laboratory setting.
Over the course of a dozen 25-minute sessions spanning four weeks, four native speakers – two women and two men – read children’s books in Mandarin and played with the children while speaking.
An English control group did the same.
The infants in the Mandarin group showed an ability to distinguish between the language’s sounds, much more so than those in the control group.
The Mandarin group’s ability to discern between “chee” and “she” was also shown to be equivalent to that of a group of Taiwanese infants exposed to Mandarin for ten months.
The infants’ ability to differentiate between the sounds lasted for 12 days – and maybe longer, as Kuhl is currently retesting and analyzing months later.
This indicates that short-term exposure to foreign language in infancy can significantly improve foreign language speech perception and retention.
Socializing Companion Study
A companion study exposed a second group of American infants to Mandarin using audiotape and DVD.
The children in this study showed no ability to distinguish between the sounds, revealing that phonetic learning is better learned and retained through social exposure.
Audio and DVD did not offer the same stimulation as a live human.
In a presentation of the studies’ findings at the American Association for the Advancement of Science, Kuhl said:
“The findings indicate that infants can extract phonetic information from first-time foreign-language exposure in a relatively short period of time at 9 months of age, but only if the language is produced by a human, suggesting that social interaction is an important component of language learning.”
Kuhl also notes that the 9-month period is a sensitive window for language learning, emphasizing the importance of timing.
She also highlighted other aspects of infant abilities in language learning, including:
“…their attraction to ‘motherese’ (a form of exaggerated speech) spoken by adults to babies; the statistical learning that infants engage in by analyzing language; and the ability to follow the gaze of another person to an object to understand what they are talking about.”