Voice-timing perception in Spanish word-initial stops

Abstract

We have shown in earlier work that speakers of Spanish differentiate voiced /bdg/ from voiceless /ptk/ in word-initial position by means of voice onset time (VOT), the temporal relation between the onset of glottal pulsing and acoustic features of supraglottal articulation. More recently, we demonstrated the perceptual efficacy of VOT for the three categories of Thai and the two of English that lie along the timing dimension. The two Spanish categories differ from those of English in that Spanish voiced stops are produced with VOT values that lead the consonant release, while voiceless stops show VOT upon release or immediately thereafter. In the present study, native speakers of Latin American Spanish identified stops synthesized with VOT varying in small steps. Their responses showed a fairly good fit between production and perception, differing from English in the expected direction. Some listeners also discriminated the variants in a psychoacoustic test format. The latter results, along with the earlier ones for English and Thai, suggest that discriminability is largely determined by language experience, although some subjects reveal considerable sensitivity to changes in the acoustic signal at some remove from the phonemic boundary.