At Dino Lingo, we get this question quite often…
Contrary to the common belief, children cannot acquire foreign languages in a shorter time span compared with older learners. This is just a myth since most people compare kids from immigrant families with their parents without keeping in mind that these children experience a higher level of foreign language exposure and go through intense formal education in the second language. Despite the earlier views about younger is the better, now many academicians seem to agree that older learners outperform children in terms of verbal analytical tasks and sophisticated use of language (Collier, 1989; Bialystok & Hakuta, 1994; Bongaerts et al., 1997).
“A common assumption is that “young children pick up a second language so fast.” What is not often taken into account by the layperson is the vast difference in the level of language complexity expected for each age. Children’s second language acquisition appears superior largely because the structures and vocabulary they need for adequate communication are so much simpler than those required of adults. In addition, children at age 6 have not yet begun to complete full cognitive development in their first language. Young children can be outperformed by older subjects on similar tasks in the second language because of the latter group’s greater cognitive maturity and the knowledge or life experience that transfers from the first to the second language. This is even more clearly demonstrated in the following summary of studies focusing on the acquisition of context-reduced, cognitively demanding aspects of oral and written school language.” (Excerpt from Collier, 1989)
However, there`s a critical period of foreign language acquisition peaking around age 6 and ending by the age of 12 (Pennfield and Roberts, 1959; Lenneberg, 1967): children are way better than adults when it comes to pronunciation and oral performance which are attributed to muscular plasticity and cerebral plasticity that naturally diminish by aging (Scovel, 1988).
Neuromuscular Control: From the phonological perspective, the sounds produced by each speaker are heavily influenced by neuromuscular coordination in the oral region. Since young learners (especially children aged 1-6) have no established articulation patterns, uttering any sound or word is way easier for them compared with adults.
Brain Plasticity: Scovel (1988) argues that lateralization of brain functions and the loss of neural plasticity before puberty –around age 12– marks the end of first language development (except vocabulary). Although there is still an ongoing debate in this area, it is proposed that lack of plasticity in the brain hinders new language acquisition because after this period language processing capacity cannot increase, L1 and L2 would be managed in different regions of the brain and higher levels of myelination becomes an impeding factor.
Some people also propose that soft palate size during early childhood, the strength of receptive memory for new words in L1 between ages 2-9 and children`s sensitivity towards different sounds (e.g. recognizing the difference between English r, French r, and Arabic r) make children better learners of foreign languages. However, so far, none of these hypotheses are scientifically tested.
Ellen Bialystok from York University explains the difference between adults and children with the shift in phonemic categorization strategies after age 5. Before the age of 5 children can establish new sound categories when they hear a new sound but later they just extend the categories they know. Bialystok (2001) also notes that adults don’t necessarily have poor cognitive skills but, aged individuals rely more on established schemes that make harder to acquire new information. The conclusion: young children are better in sound recognition and pronunciation but when it comes to learning a whole language, it is a totally different story.
References
Scovel, Thomas. 1988. A time to speak: a psycholinguistic inquiry into the critical period for
human speech. Rowley, MA: Newbury House.
Penfield, W. & Roberts, L. (1959). Speech and brain mechanisms. Princeton, NJ:
Princeton University Press.
Lenneberg, Eric. 1967. Biological foundations of language. New York, NY: Wiley.
Bialystock, E. & Hakuta, K. (1994) In Other Words: The Science and Psychology of Second-Language Acquisition. New York, NY: Basic Books
Bongaerts, T., Summeren, C., Planken, B., & Schils, E. (1997). Age and ultimate attainment in the pronunciation of a foreign language. Studies in Second Language Acquisition, 19, 447–466.
Collier, V.P. (1989). How long? A synthesis of research on academic achievement in a second language. TESOL Quarterly, 23, 509-531.
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