The proposed research evaluates a model of speech learning by examining the changes in speech production, speech perception, and speech processing that occur when individuals are exposed to the phones found in a foreign language (L2). One important hypothesis to be tested is that equivalence classification prevents individuals who learn an L2 after the age of 12;0 years (late L2 learners), but not those who learn an L2 before the age of 7;0 years (early L2 learners), from producing similar L2 phones authentically. It is hypothesized that early but not late L2 learners establish a phonetic category for similar L2 phones. As a result, early L2 learners with sufficient L2 experience will produce similar L2 phones authentically by implementing them with a different phonetic category than their counterparts in the native language (L1). Late L2 learners, on the other hand, do so by forming a phonetic realization rule with which to produce similar L2 phones. Equivalence classification should not prevent either early or late L2 learners from establishing a phonetic category for new L2 phones which have no counterpart in L1. It is hypothesized that early and late L2 learners develop different phonetic systems because equivalence classification differentially affects their use of the sensory information associated with similar L2 phones as a function of age of learning. These hypotheses are tested in an integrated series of 13 experiments which will examine spontaneous speech production, rapid switches in speech production between L1 and L2, imitation, speeded classification, similarity scaling, and AX discrimination. The research culminates in a training study that aims to precipitate the establishment of a phonetic category for a similar L2 phone through auditory or motor skill training.

National Institute of Health (NIH)
National Institute of Neurological Disorders and Stroke (NINDS)
Research Project (R01)
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Communication Sciences and Disorders (CMS)
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University of Alabama Birmingham
School of Medicine & Dentistry
United States
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Moeini, S M; Flege, J E; McCutcheon, M J (1990) The design of a microcomputer-controlled voice onset time analyzer. Biomed Instrum Technol 24:357-62
Flege, J E (1989) Chinese subjects' perception of the word-final English /t/-/d/ contrast: performance before and after training. J Acoust Soc Am 86:1684-97
Flege, J E (1988) Factors affecting degree of perceived foreign accent in English sentences. J Acoust Soc Am 84:70-9
Flege, J E; Eefting, W (1988) Imitation of a VOT continuum by native speakers of English and Spanish: evidence for phonetic category formation. J Acoust Soc Am 83:729-40
Flege, J E; Fletcher, S G; McCutcheon, M J et al. (1986) The physiological specification of American English vowels. Lang Speech 29 ( Pt 4):361-88
Flege, J E; Hillenbrand, J (1986) Differential use of temporal cues to the /s/-/z/ contrast by native and non-native speakers of English. J Acoust Soc Am 79:508-17
Flege, J E; Eefting, W (1986) Linguistic and developmental effects on the production and perception of stop consonants. Phonetica 43:155-71