summary + worksheet (short article)

Learning a Language as an Adult

The question of how people learn an additional, or second language (L2), has received a great deal of attention from scholars. Their research has offered evidence for a number of conflicting claims about L2 learning. However, there is no dispute about one fundamental observation. It is possible, and quite common, for adults to achieve a high degree of success in learning L2 vocabulary, and even grammar. In their vocabulary and sometimes their grammar, they may become very much like a native speaker. The same degree of success is relatively rare in L2 pronunciation, however. Second language speakers’ pronunciation is related to the age at which they are first exposed to the L2. This is the single best predictor. Of how closely their pronunciation will approximate the accent of native speakers. Speakers who are very young when they were first exposed to their L2 almost always have better pronunciation than those who were exposed at an older age.

Results from a number of research studies offer evidence for the existence of this phenomenon. They support the basic rule that “younger is better in the long run”. Older learners may begin with an advantage, presumably because they have superior cognitive abilities. However, eventually, youngers learners always catch up and overtake older learners, especially in pronunciation. It is important to stress that this has been shown in second language contexts, that is, where learners are living in the L2 community and receiving constant exposure to the L2. The same results have not been demonstrated in situations in foreign language learning, where learners live in the first language community and their primary exposure to the L2 is in the classroom.

How have scientists accounted for the fact that adult learners rarely attain nativelike pronunciation in the L2? One explanation is the critical period hypothesis. This idea has a much broader application than L2 learning and extends to other animals and other kinds of learning. The hypothesis states that if an animal or human does not receive the necessary stimulation during a critical period of development, it will not develop a specific ability. For example, baby cats that do not receive visual stimulation during a particular period will grow up blind, although there is nothing wrong with their eyes. Baby birds that are not exposed to the song of their species will not develop normal songs. Their songs will sound different.

These ideas have important implications for language learning. Proponents of the critical period for language learning argue that complete acquisition of language is only possible before cerebral lateralization ends about the age of twelve. Cerebral lateralization occurs when two hemispheres of the brain increasingly specialize in particular functions. At the end of this process, control of most, although not all, language function is permanently located in the left hemisphere. The right hemisphere is responsible, among other things, visual and spatial perception. When lateralization is complete, according to the theory, the critical period closes. This is the period during which most humans can achieve nativelike mastery of a language, particularly in the area of pronunciation.

There is not a lot of evidence for the critical period for first language learning because there are not many situations in which children have no exposure to language until they are 12 years old. There have been just a few cases of modern feral children, or children who have grown up away from adults and civilization. There is also one famous case of Genie, a child abused by her parents locking her in a room and never speaking to her. The authorities found her when she was 13 years old. Both in her case and the case of feral children, the critical period hypothesis was supported: These individuals never fully mastered language. They acquired an extensive vocabulary, but their grammar and pronunciation were not nativelike.

There is more evidence for the critical period hypothesis for L2 learning than for first language learning. It seems to apply most strongly to pronunciation. It suggests that learners who wish to acquire a nativelike accent need to begin when they are children and that adult learners are unlikely ever to attain that goal. Nevertheless, there are counterexamples. There are adult L2 learners who can pass as native speakers, and there are learners who, with extensive exposure to the L2 as children, are not nativelike in their L2 as adults. However, both of this are relatively rare. In addition, there does not seem to be a precise age at which complete mastery is no longer possible. The ability to pronounce L2 like a native speaker does not disappear suddenly; instead, it declines gradually. For this reason, many L2 researchers prefer the term sensitive period to critical period.

It should be emphasized that these ideas do not justify an end to the teaching of L2 pronunciation. It is possible for learners to achieve very good pronunciation in the L2 through instruction, hard work, and practice. Second language learners can develop speech that is grammatical, expressive, and perfectly comprehensible. They do not need to sound like native speakers.