Patricia Kuhl – Success Across Cultures

Exposure to foreign language early on can aid future language learning.

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”

The Mandarin sounds, “chee” and “she,” are difficult for adult Americans to differentiate.

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.”

Why do Americans struggle with differentiating between the “shee” (“west”) and “chee” (“wife”) sounds in Mandarin?

Why do the Japanese struggle with the “l” and “r” sounds in “lake” and “rake”?

University of Washington speech professor Patricia Kuhl has the answer.

Map-Building

Having studied early language development for nearly three decades, Kuhl has a better understanding than most of how and when pronunciation and accents develop.

Before a baby even speaks her first word, a pattern of speaking has formed in the brain, based on her primary caregiver’s speech.

With American, Japanese, Swedish, and Russian infant participants, Kuhl found that vowel and consonant sounds of both native and foreign languages are clearly recognized by children between 6 to 8 months.

That means an American infant can recognize and respond to the differences in “shee” and “chee,” while the Japanese infant will differentiate between “l” and “r” just as easily as an American.

Head-Turn Study

Kuhl used a “head-turn” study to identify whether infants could recognize these sounds.

While distracting an infant with a toy, the speaker would repeat a sound over and over – “la, la, la,” for instance.

The infant would continue watching the toy until she would hear a different sound mixed in – “la, la, ra” – which would then light up the toy.

In anticipation of the reward, two-thirds of both Japanese and American 6- to 8-month-old infants would turn to look at the toy when the sound changed.

That ability was lost by the time the child reached one year.

Using the same sounds, a little over half of Japanese infants and nearly four-fifths of Americans would turn to look at the toy by the time the infants had reached a year.

The study concluded that this is when native sounds become the baby’s norm.

Magnet Effect

A Smithsonian article by Edwin Kiester, Jr., throws this map-building into further relief, with Kuhl describing the mapping of the baby’s language brain:

“The baby early begins to draw a kind of map of the sounds he hears. That map continues to develop and strengthen as the sounds are repeated. The sounds not heard, the synapses not used, are bypassed and pruned from the brain’s network. Eventually the sounds and accent of the language become automatic.”

A “magnet effect” further maps the native language, as prototypical sounds are absorbed and interpreted as native, while foreign sounds are discarded as “interference.”

And what of infants born in bilingual households?

Those infant brains simply draw multiple maps, which is made easier if a specific language is spoken in the pitch, tone, and pronunciation of either caregiver.

This is why foreign languages are difficult to learn into adulthood: your language brain has long been mapped, and it’s a struggle to tune into sounds your brain wiring perceives as “interference.”

But this does not mean it’s impossible.

We’ll talk about the possibility next week.

Tag: Patricia Kuhl

Early Language Mapping: How Infants Learn Pronunciation