By Chia-wa Yeh, Head Teacher and Research Coordinator
Are bilingual children more sensitive to non-verbal gestures in communication than monolingual children? Are they better able to interpret speakers’ intent? These are the questions Wei Quin Yow aims to answer through a series of studies conducted at Bing over the past three years.
A 5th-year graduate student in psychology, Yow studies under the guidance of professor Ellen Markman, Ph.D., Yow has a dual role at Bing, both as a parent and a researcher. She has two daughters, Angie, 6, a Bing alumna, and Zoe, 3, currently at Bing. Yow is from Singapore and speaks three languages (Cantonese, mandarin Chinese and English) from early childhood. After graduating from university with honors, Yow obtained a master’s degree in statistics at Stanford. Petite, energetic and a fast speaker, Yow is also an accomplished Chinese martial artist. She started learning Tai Chi in college and won several national and international titles in Wushu, a Chinese martial art, including a silver medal in the South East Asian Games in 2003.
Yow’s main research focus is the social cognitive impact of bilingualism. Specifically, whether bilingual children are better able to notice cues such as non-verbal referential gestures (pointing and eye gaze) as well as tone of voice compared with monolingual children. Her studies are designed to provide a social context, i.e., interaction between a child and a researcher, and investigate children’s understanding of the speaker’s intent in different circumstances.
For her study, Yow defines bilingual as being exposed to two languages—hearing or speaking the less-predominant of the two at least 30 percent of the time. Yow’s findings supported her hypothesis. The implication is “if the results hold true, growing up bilingual will actually facilitate the development of social cognitive competence,” said Yow. The results suggest that bilingual children are able to integrate multiple cues to have successful communication and that they might attain these skills much earlier than monolingual children.
Yow has conducted a series of four studies at Bing in the past three years. The first study looked at 3- to 5-year-olds’ use of non-verbal referential cues—looking or pointing—to find a hidden toy. Children were presented with two boxes, one of which contained a novel object (for example, a garlic press, or a massage tool shaped like six-pointed star, resembling a giant piece from a game of jacks.) To indicate the right box, the researcher either pointed at it or looked at it with focused attention. In one condition, the researcher sat equidistant between the two boxes. In another condition, the researcher sat behind the empty box while providing the cue to the correct box.
Yow hypothesized that bilingual children would be better at using these cues to locate the hidden object. The study showed this to be the case in some but not all situations. Both monolingual and bilingual 3- and 4-year-olds are able to use gaze and point as cues to retrieve the hidden toy except in the most challenging condition—when researchers sat directly behind the empty box and used eye gaze as the cue. This condition is especially confusing because of the researcher’s proximity to the empty box and the less direct cue of eye gaze. In this case, bilingual children were better able to use the eye gaze as a cue to retrieve the hidden object than monolingual children. By 5 years of age, there was no difference between bilingual and monolingual children in using the eye gaze as a cue in the more challenging position.
The second study examined children’s more complex understanding of a speaker’s referential intent. For example, were bilingual children simply following the researcher’s point or eye gaze indiscriminately? Or were they showing a more sophisticated understanding of the context? To find out, a researcher sitting across a table from children, showed 3-year-olds a box with two compartments, each with a window [see photo]. In the study, a screen the width of one compartment covered sometimes one window and sometimes the other. The researcher showed children two novel objects without referring to them by name and then turned around to look elsewhere while a second researcher placed each of the objects in separate compartments and covered one with the screen. The box was oriented so that when the first researcher turned back to face the children, the screen blocked her view of one compartment while children had a full view of the objects in both compartments. The first researcher then turned back and fixed her eye gaze at the object in the open window and said either “There’s the gorp. (“Gorp” was one of the made-up words used in the study for the novel objects.) Can I have the gorp?” in which case the speaker was looking for the visible object, or “Where’s the gorp? Can I have the gorp?” in which case the speaker was looking for the object blocked by the screen.
While all 3-year-olds understood gaze equally well when the researcher used it to refer to the mutually visible object in the open window and said, “There’s the _____,” bilingual children were better at understanding the speaker’s use of gaze to refer to the hidden object when the researcher asked “Where.” The result showed that 3-year-old bilingual children are better able to integrate linguistic demand [there vs. where] with eye gaze than their monolingual counterparts.
Yow then found that the combination of a questioning gesture (palms faced up, raised to shoulders) and explicit searching (looking at the open compartment, looking to the blocked window, looking back at the open compartment and then asking “Where’s the _____?”) helped monolingual children discern the speaker’s intent.
In the third series of studies, children listened to audio recordings of sentences of happy or sad content with matching and incongruent tones. For example, “My mother gave me a treat,” was spoken in high-pitched tone with fast tempo or low-pitched tone with falling intonation. Past research showed that adults tend to rely on the speakers’ intonation (paralanguage) in incongruent situations to judge their emotion. However, children depend largely on the content. Yow hypothesized that bilingual children would be better at factoring in speakers’ paralinguistic cues to determine if they are feeling happy or sad. The results showed that bilingual children were significantly more likely than monolingual children to use paralinguistic cues to judge emotion when content conflicted with the manner in which it was spoken.
What if the linguistic content is filtered out in such a way that it’s no longer intelligible but the intonation and tempo remain intact? Using the same recordings but passed through a filter, Yow found that monolingual and bilingual children are equally capable of identifying if the speaker was feeling happy or sad when the content was unintelligible.
In the fourth study, Yow designed a protocol that uses both non-verbal gestures and intonation, combining elements in the second and third studies. Researchers again used the box with two compartments. The difference in this study was that they tried different intonations, serious vs. playful, when they asked children to locate an object. The serious tone implied that the speaker was looking for something not in view whereas the playful intonation implied that the speaker was searching for what was visible. As predicted, the results found that bilingual children were better than monolingual children at identifying the object in both conditions.
What is the importance of these studies?
It is important to understand whether growing up bilingual has any social cognitive impact on children, and if there is, then what that might be, said Yow. If the results hold true (Yow recognized that there are a number of variables to consider), Yow would advocate for the introduction of a second language to children, starting at a young age, to facilitate the development of these social cognitive skills.
Does bilingualism have long-term benefits in the social cognitive domain?
These findings pertain mainly to 3- to 5-year olds. Researchers must develop other designs to see if the bilingual advan-tages shown in Yow’s studies similarly extend to young adulthood, or even old age. Yow cited research indicating that bilingualism slows down cognitive decline. It is supported by studies on inhibitory control comparing monolingual and bilingual seniors.
What can parents do if they speak one language?
Yow acknowledged that the decision to expose children to more than one language is a personal choice that depends greatly on individual family situations and values. However, parents who speak one language need not despair, Yow said. They can engage in activities with their children to develop cognitive skills. For example, Simon Says is a game through which children can practice inhibitory control, i.e., recognizing the cues and performing the appropriate actions.
Bing Nursery School is part of Stanford’s psychology department, serving as a laboratory for research in child development and a site for training undergraduates. This past year, 16 studies took place at Bing. One of these was Yow’s. Researchers spend time in the classroom to get to know the children before inviting them to participate in the study, which is usually presented as a game. Children take part in studies about once or twice a month, depending on the number of projects and the age range with which researchers are working.