Many words have more than one meaning. In the course of language acquisition, children learn to understand what is meant from the context. However, how exactly and in what order they acquire the various meanings has so far been unclear. Researchers have now automatically evaluated a large data set of natural communication between children and their caregivers. Accordingly, concrete word meanings are present earlier than abstract ones. Understanding expands gradually, with more similar word meanings being easier to learn than less similar ones. Individual language acquisition reflects fundamental mechanisms of language development throughout history.
When a toddler talks about a ball, he or she is probably referring to a toy rather than a dance event. A mouse probably first learns about it as an animal and not as an input device for a computer. But over time he learns that the words can also have a different meaning. “Children as language learners acquire these different meanings of a word in the course of language development, but it is not yet fully understood how they acquire them and in what order,” explains a team led by Jiangtian Li from the University of Toronto Scarborough in Canada.
From concrete to abstract
In order to gain more detailed insights into the underlying processes, the researchers used a data set that contains transcriptions of millions of conversations between children and their caregivers. Using artificial intelligence, Li and his colleagues evaluated around four million utterances and extracted 1,270 ambiguous words. They automatically recorded the different meanings for each of these words and recorded when the children between the ages of 19 months and twelve years integrated the respective meanings into their vocabulary.
It turned out that certain meanings are apparently easier to learn than others: “We found evidence that the expansion of meaning develops from concrete to abstract meanings as children get older,” reports the team. For example, a toddler usually first gets to know the English word “stick” as meaning “stick”. Later it also learns the meaning “to stick in” and even later the meaning “to stick”.
Although children learn words primarily by hearing how others use them, this development from concrete to abstract cannot be explained solely by the language use of their caregivers. As the team found, the toddlers heard the respective words in their more abstract sense early on in their environment. However, it took significantly more time for them to use them themselves than with the more concrete meanings of the words. “This suggests that the emergence of different meanings in children is determined by the child’s own premises and that children do not simply imitate the connections that are conveyed to them by caregivers at different ages,” the researchers conclude.
Gradual expansion
The researchers also found that children apparently find it easier to learn a new meaning of a word if it is related to the meaning they already know. If you already know that plants have roots, it makes sense to apply the principle to teeth – and later to a common root in a more abstract sense. The garden shed, on the other hand, has little to do with the scales of a fish, so that these two meanings are typically understood at a greater distance in time. “As children get older, the meanings gradually expand,” explains the research team. “New meanings are linked to semantically related meanings that children have already learned.”
A similar principle can also be observed in the historical development of language. Here, too, words usually first appeared in their more concrete meaning and later expanded their meaning to include more abstract concepts. “Our work suggests that the development of word meaning in language acquisition is similar to that in language development,” Li and his team write. “These regularities and mechanisms suggest a common cognitive basis for the emergence of word meanings in ontogeny and phylogeny.”
Source: Jiangtian Li (University of Toronto Scarborough, Canada) et al., Proceedings of the National Academy of Sciences, doi: 10.1073/pnas.2525788123