Perception of Voice Timing in Spanish Stop Consonants

Abstract

In earlier acoustic analysis of Spanish, we showed that speakers 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 Thai, a language with three categories along the timing dimension, and English, a language with two categories. The two Spanish categories differ from those of English in their placement of the phonetic boundary. 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 Spanish identified randomized recordings of stops synthesized with VOT varying in small steps. Labeling responses showed a fairly good fit between production and perception differing from English in the expected direction. The listeners also discriminated the VOT variants in a psychoacoustic test format. The latter results, along with the earlier ones for English and Thai, indicate that discriminability is primarily determined by specific language experience, although general phonetic categories may have some effect.