Age of Learning and Second Language Speech
James E. Flege University of Alabama, Birmingham
In this chapter, we consider the relation between the age at which the naturalistic acquisition of a second language (L2) begins, and the accuracy with which the L2 is pronounced. Quite clearly, earlier is better as far as L2 pronunciation is concerned. However, the widely accepted critical period hypothesis does not appear to provide the best explanation for this phenomenon.
Although it is widely agreed that "earlier is better" as far as the pronunciation of an L2 is concerned, there is disagreement as to the exact nature of the relation between the age of L2 learning and degree of foreign accent, as well as the cause(s) of foreign accent (see Singleton, 1989, for a review). Long ( 1990) concluded from a review of previously published studies that an L2 is usually spoken without accent if learning begins by the age of 6, with a foreign accent if learning begins after the age of 12, and with variable success between the ages of 6 and 12. Patkowski ( 1990) concluded that the dramatic difference he noted in the foreign accents of participants who had first arrived in the United States before versus after the age of 15 was due to the passing of a critical period, which he defined as an "age-based constraint on the acquisition of full native fluency" in an L2. Indeed, Patkowski claimed that individuals who begin learning an L2 before versus after the critical period differ in a "fundamental, qualitative way" (p. 74).