It is thought that children "pick up" languages naturally, whereas adults must study grammar in order to learn a second language (L2). Adult L2 learners typically develop extensive explicit knowledge about the L2 (knowledge that is conscious and can be verbalized), but may lack implicit knowledge (knowledge that cannot be verbalized, but can be accessed quickly and easily.) The reverse is typical of children. But children also experience a very different learning environment from adults. Are age differences in implicit/explicit language knowledge maturational, or environmental?

This dissertation research explores how adults and children in different learning conditions develop implicit and explicit L2 knowledge, specifically asking (1) whether children favor implicit knowledge, (2) whether adults favor explicit knowledge, and (3) whether this still holds when children and adults are under the same controlled training conditions. Such research has not been done to date, since research on implicit/explicit knowledge only tests adults, and research on children has not included task comparisons.

With support from the National Science Foundation, two studies addressing explicit and implicit knowledge in children and adults will be carried out. The first tests child and young adult L2 learners of Spanish who have had similar instructional experiences on their implicit and explicit knowledge of verb morphology. The second study trains adults and children to speak an artificial mini-language; half the subjects receive explicit rule instruction, and the other half do not. The goal of these studies is to examine whether age or instruction is the primary factor in determining reliance on explicit vs. implicit knowledge. This research contributes to the discussion of whether child and adult language learning are fundamentally similar or different, helping to develop theories of language learning across the lifespan. Results are expected to have implications for the development of effective pedagogy for different age groups.

Project Report

It is generally believed that adults must learn grammar rules in order to master a foreign language, but that children can simply pick up language from hearing it. In other words, adults, but not children, need explicit information about language structure. This project is the first to actually test these ideas by directly comparing child language learners to adult language learners, under the same controlled instructional conditions. The studies in the project compare elementary school children to high school children, and children age 5-7 to adults. Participants in the first study were students of Spanish, and participants in the second study were taught an artificial mini-language during the study. Surprisingly, the studies find that when children are taught grammar rules, they seek out and use explicit information about language—just like adults. And, adults who have never had explicit grammar instruction do not seek out and use explicit information about language. Rather, they pick up languages from hearing them, like children. Whether the learner is a child or an adult, implicit learning takes time, but leads to knowledge that can be accessed more quickly and automatically (for example, during a conversation in a foreign language.) Explicit learning happens faster, but is difficult to apply quickly, regardless of age. This means that children and adults may be more similar as language learners than previously thought. From a theoretical standpoint, the results suggest that exposure to explicit information about language, and not simply maturation, is responsible for a shift from more implicit learning to more explicit learning over the course of the lifespan. From a research methodology standpoint, these studies show that tasks tapping explicit knowledge can be designed to be appropriate for children, and even appropriate for both children and adults. This is important since few studies of children test their explicit knowledge, and children, like adults, may show differences in performance between tasks. And, with respect to pedagogy, these studies show that both children and adults have the capacity to learn implicitly or explicitly, under the right instructional conditions. Teachers can use this information, along with knowledge of their students’ background experiences and goals, to decide what kind of implicit or explicit teaching methods will be most beneficial.

National Science Foundation (NSF)
Division of Behavioral and Cognitive Sciences (BCS)
Standard Grant (Standard)
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William J. Badecker
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University of Illinois Urbana-Champaign
United States
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