Білім беру бағдарламасына арналған торм 5206 тілдерді оқытудағы психологиялық МӘселелер пәні бойынша лекция тезистерінің жинағы

One of the most promising areas of inquiry in age and acquisition research has been the study of the function of the brain in the process of acquisition. How might neurological development affect second language suc­cess? Does the maturation of the brain at some stage spell the doom of language acquisition ability?

Some scholars have singled out the lateralization of the brain as the key to answering such a question. There is evidence in neurological research that as the human brain matures, certain functions are assigned, or "lateralized," to the left hemisphere of the brain, and certain other functions to the right hemisphere. Intellectual, logical, and analytic functions appear to be largely located in the left hemisphere, while the right hemisphere controls functions related to emotional and social needs. Language functions appear to be controlled mainly in the left hemisphere, although there is a good deal of conflicting evidence. For example, patients who have had left hemi-spherectomies have been capable of comprehending and producing an amazing amount of language. But in general, a stroke or accident victim who suffers a lesion in the left hemisphere will manifest some language impairment, which is less often the case with right hemisphere lesions.

While questions about how language is lateralized in the brain are interesting indeed, a more crucial question for second language researchers has centered on when lateralization takes place, and how that lateralization process affects language acquisition. Eric Lenneberg (1967) and others sug­gested that lateralization is a slow process that begins around the age of two and is completed around puberty. During this time the child is neurologically assigning functions little by little to one side of the brain or the other; included in these functions, of course, is language. And it has been found that children up to the age of puberty who suffer injury to the left hemisphere are able to relocalize linguistic functions to the right hemi­sphere, to "relearn" their first language with relatively little impairment. Thomas Scovel (1969) extended these findings to propose a relationship between lateralization and second language acquisition. He suggested that the plasticity of the brain prior to puberty enables children to acquire not only their first language but also a second language, and that possibly it is the very accomplishment of lateralization that makes it difficult for people to be able ever again to easily acquire fluent control of a second language, or at least to acquire it with what Alexander Guiora et al. (1972a) called "authentic" (nativelike) pronunciation.

While Scovel's (1969) suggestion had only marginal experimental basis, it prompted him (Scovel 1988) and other researchers (e.g., Singleton & Lengyel 1995) to take a careful look at neurological factors in first and second language acquisition. This research considered the possibility that there is a critical period not only for first language acquisition but also, by extension, for second language acquisition. Much of the neurological argu­ment centers on the time of lateralization. While Lenneberg (1967) con­tended that lateralization is complete around puberty, Norman Geschwind (1970), among others, suggested a much earlier age. Stephen Krashen (1973) cited research to support the completion of lateralization around age five. Krashen's suggestion does not grossly conflict with research on first language acquisition if one considers "fluency" in the first language to be achieved by age five. Scovel (1984) cautioned against assuming, with Krashen, that lateralization is complete by age five. "One must be careful to distinguish between 'emergence' of lateralization (at birth, but quite evi­dent at five) and 'completion' (only evident at about puberty)." If lateraliza­tion is not completed until puberty, then one can still construct arguments for a critical period based on lateralization.