Age of Learning Affects Rate-Dependent Processing of Stops in a Second Language

Abstract

The aim of this study was to assess the effect of speaking rate changes on the perception of English stop consonants by four groups of subjects: English and Spanish monolinguals, ‘early’ Spanish/English bilinguals who learned English in childhood, and ‘late’ bilinguals who learned English in adulthood. Subjects identified, and then later rated for goodness as exemplars of the English /p/ category, the members of two voice onset time (VOT) continua. The English monolinguals identified a well-defined range of VOT stimuli as English /p/, and stimuli with longer VOT values as ‘exaggerated’ instances of English /p/. Their goodness ratings increased as VOT increased, then showed a systematic decrease as VOT began to exceed values typical for English /p/. The English monolinguals’ goodness ratings also varied systematically as a function of speaking rate, which was simulated in the two continua by varying syllable duration. The Spanish monolinguals, on the other hand, failed to consistently identify any of the stimuli as English /p/. Although speaking rate influenced their goodness ratings, the Spanish monolinguals’ rate effects differed significantly from the English monolinguals’. The early bilinguals resembled the English monolinguals, and differed from the Spanish monolinguals to a greater extent than did the late Spanish/English bilinguals. This was taken as support for the hypothesis that early bilinguals are more likely than are late bilinguals to establish new phonetic categories for stop consonants in a second language.

Category restructuring during second-language speech acquisition

“…In our view, the limits on learning observed in this study arose from the influence of previous phonetic learning and the distribution of L1 and L2 phonetic input that was received, not maturational constraints due to normal neurological development ͑e.g., Scovel, 1988͒. According to the SLM ͑Flege, 1995͒, L1 sounds will exert less influence on the perception and production of an L2 speech sound for which an independent category has been established. As a result, L2 sounds for which a category has been formed will be perceived and produced in a more nativelike fashion than L2 sounds that are processed using a merged category ͑see, e.g., Flege et al, 1996a. It is important to note, however, that the present study did not provide direct evidence that the Italian-English bilinguals did not establish new categories for English /b d g/.…”

The Identification of English Consonants by Native Speakers of Italian

“…Most previous L2 research has focused in detail on just a few L2 consonants [e.g. Lively et al, 1993;Flege et al, 1996a], but we chose to examine 18 consonants of English. 4 This approach prevented us from obtaining a large number of judgments of each consonant and, thus, limited our ability to draw inferences concerning the use of specific features, or the effect of variation in cross-language phonetic distance, on the identification of various consonants.…”

Effects of syllable-initial voicing and speaking rate on the temporal characteristics of monosyllabic words

“…5 Beyond their main argument, Kessinger and Blumstein ͑1998͒ point out another potential problem with the traditional method of creating VOT continua. The problem concerns those perceptual studies that include stimuli deliberately created to be poor exemplars, specifically, stimuli whose VOT values are unnaturally long and whose vowel durations are correspondingly unnaturally short ͑e.g., Flege et al, 1996;Miller and Volaitis, 1989;Volaitis and Miller, 1992͒. Kessinger and Blumstein argue that these stimuli are not only unnatural, but that the perceived identity of the vowel might be altered due to the very short vowel.…”