Voicing contrast: perceptual and productive voice onset time characteristics of adults.

Abstract

This study was designed to examine the status of voice onset time (VOT) in identification and production of word-initial voiced and voiceless labial, apical, and velar stop consonants for 20 English-speaking adults. Synthetic speech stimuli were constructed for four continua including BEES/PEAS, BEAR/PEAR, DIME/TIME, and GOAT/COAT. VOT values for 30 productions of the same words examined in the identification task were determined from spectrographic measurements. Analyses of the perceptual data revealed significant differences among labial, apical, and velar stops for the VOT 50% crossover and lower and upper limits of the phoneme boundary, but not for boundary width. In production of voiced and voiceless stops, reliable differences for mean VOT were shown between all cognates and among places of articulatory constriction within voicing category. The latter finding was primarily related to the labial/velar comparisons. Variability among individual speakers was demonstrated in the percentage of voiced stops associated with VOT values in the lead portion of the continuum, whereas all subjects evidenced productions in the short lag range. Comparisons between identification and production demonstrated high consistency for VOT characteristics in that few productions coincided with the perceptual phoneme boundary or contrasting voicing category.