Your child, an experienced language learner

A new study from MIT’s Language Learning Laboratory offers new insight into this issue: Sentences contain subtle hints in their grammar that tell young children the meaning of new words. The finding, based on experiments with two-year-old children, suggests that even very young children are able to learn the grammatical cues of language and use this information to learn new words.

“Even at a surprisingly young age, children have a deep knowledge of sentence grammar and can use it to learn the meanings of new words,” says Athulya Aravind, assistant professor of linguistics at MIT.

The new finding contrasts with a previous explanation for how children build vocabulary: They rely on the concept of “mutual exclusivity,” meaning they view each new word as corresponding to a new object or category. Instead, new research shows how much children respond directly to grammatical information when interpreting words.

“This is really exciting for us because it’s a very simple idea that explains so much about how children understand language,” says Gabor Brody, a postdoc at Brown University who is the paper’s first author.

The article is called “Why do children think words are mutually exclusive?” It is published in advance in online form at Psychological Science. Authors: Brody; Roman Feiman, Thomas J. and Alice M. Tisch Assistant Professor of Cognitive and Psychological Sciences and Linguistics at Brown University; and Aravind, the Alfred Henry and Jean Morrison Hayes Assistant Professor of Linguistics and Philosophy at MIT.

Focusing

Many scientists believed that young children, when learning new words, have an innate tendency toward mutual exclusivity, which may explain how children learn some of their new words. However, the concept of mutual exclusivity has never been flawless: words like “bat” refer to many types of objects, while any object can be described using countless words. For example, a rabbit can be called not only “bunny” or “bunny”, but also “animal”, or “beauty”, and in some contexts even a “delicacy”. Despite the lack of a perfect one-to-one correspondence between words and objects, mutual exclusivity is still considered a strong trend in children’s word learning.

Aravind, Brody and Faiman suggest that children do not have this tendency and instead rely on so-called “focus” cues to decide what a new word means. Linguists use the term “focus” to refer to the way we emphasize or emphasize certain words to indicate some kind of contrast. Depending on what the focus is on, the same sentence can have different meanings. “Carlos gave Lewis Ferrari” implies a contrast with other possible cars – he could have given Lewis a Mercedes. But “Carlos gave Lewis Ferrari” suggests a contrast with other people – he could give Alexandra a Ferrari.

Experiments The researchers manipulated focus in three experiments involving a total of 106 children. Participants watched a video of a cartoon fox who asked them to point to different objects.

The first experiment established how children’s attention influences the choice between two objects when they hear a label, such as “toy,” which could in principle correspond to either of the two objects. Having given a name to one of the two objects (“Look, I’m pointing to the blacket”), the fox said to the child: “Now you point to the toy!” The children were divided into two groups. One group heard the word “toy” without an accent, while the other heard it with an accent.

In the first version, “blicket” and “toy” quite likely refer to the same object. But in the second option, the added emphasis through intonation implies that the “toy” contrasts with the previously discussed “blicket.” Without the focus, only 24 percent of respondents believed the words were mutually exclusive, whereas with the focus, created by emphasizing the word “toy,” 89 percent of participants believed that “blicket” and “toy” referred to different objects.

The second and third experiments showed that not only was focus key when it came to words like “toy,” but it also influenced the interpretation of new words that children had never encountered before, such as “vag” or “dax.” ” If a new word was spoken without attention, children 71 percent of the time thought that the word meant the previously named object. But when they heard a new word spoken with concentration, they thought it must refer to the new object 87 percent of the time.

“Although they knew nothing about this new word, when it was focused, it still told them something: the focus informed children that there was a contrasting alternative, and they accordingly understood that the noun referred to an object that had not previously been designated as “,” explains Aravind.

She adds: “The particular claim we make is that children do not have an innate bias towards mutual exclusivity. The only reason we draw the appropriate conclusion is because the trick tells you that the word means something different from another word. away, children no longer make such conclusions about exclusivity.”

The researchers believe the full set of experiments sheds new light on the problem.

“Earlier explanations of mutual exclusivity created a whole new problem,” Feiman says. “If children assume words are mutually exclusive, how do they learn words that are not mutually exclusive? After all, you can call the same animal either a bunny or a bunny, and at some point kids will have to learn both. Our discovery explains why this isn’t really a problem. Children won’t think that a new word is mutually exclusive with an old one by default unless adults tell them it is – all adults have to do if a new word is not mutually exclusive is just say it without concentrating on it , and they will naturally do so if they consider it compatible.”

Learning a language through language

The experiment, the researchers note, is the result of interdisciplinary research combining psychology and linguistics—in this case, mobilizing a linguistic concept to solve a problem of interest in both fields.

“We hope this paper shows that small, simple theories have a place in psychology,” Brody says. “It’s a very small theory, not a huge model of the mind, but it completely changes some phenomena that we thought we understood.”

If the new hypothesis is correct, the researchers may have developed a more reliable explanation for how children use new words correctly.

“An influential idea in language development is that children can use their existing knowledge of language to learn more language,” says Aravind. “In a sense, we are taking this idea further and saying that even in the simplest cases, aspects of language that children already know, in this case understanding tricks, help them understand the meanings of unknown words.”

Scientists acknowledge that additional research could further expand our knowledge on this issue. Future research, they note in the paper, could revisit previous research on mutual exclusivity, document and examine naturalistic interactions between parents and children to see how focus is used, and explore this issue in other languages, especially those that mark focus with alternatives. ways, such as word order.

The research was supported in part by a Jacobs Foundation Fellowship awarded to Feiman.