Duration and rate effects on English vowel identification by native Spanish listeners

Abstract

Several American English vowel contrasts are specified by co-varying formant frequency and duration information. Listeners alter their vowel identification according to speaking rate, apparently making judgments about relative vowel duration. Two series of spectral continua were previously created from natural speech, ‘‘beat-bit’’ and ‘‘pat-pet,’’ varying F1 and F2, and syllable duration [Berman et al., J. Acoust. Soc. Am. 105, 1402 (1999)]. These syllables were inserted into sentence contexts of two rates (normal and fast). Longer syllable duration led to more ‘‘beat’’ and ‘‘pat’’ responses; faster rate contexts also led to more ‘‘beat’’ and ‘‘pat’’ responses. The present research tested native speakers of Spanish on their use of duration and rate context in English vowel identification. Despite the absence of Spanish vowel contrasts based on duration, native Spanish listeners were significantly affected by syllable duration and sentence rate in their identification of the ‘‘beat-bit’’ contrast. They also showed a significant duration effect for ‘‘pat-pet,’’ but the magnitude of this duration effect was significantly smaller for these non-native listeners than for native listeners, and there was no significant effect of sentence rate. With less English experience, non-natives might show even smaller effects of duration and sentence rate.