A voiced onset time analysis of word-initial stops in Thai

Abstract

Voice onset time (VOT) is defined as the temporal relation between the onset of glottal pulsing and the release of the initial stop consonant (Lisker & Abramson, 1964, 1967). Voicing detected before the release is called voicing lead, while voicing starting after the release is called voicing lag. Lisker & Abramson (1964) found that VOT is a good index to laryngeal timing for stop-consonant distinctions in word-initial position across a variety of languages. Although VOT generally refers to the timing relation between the burst release and onset of glottal pulsing, it, in fact, represents a constellation of acoustic attributes including the intensity and duration of the burst release, cutback and starting frequency of the first formant, and the presence or absence of frication noise upon consonantal release (Lisker & Abramson, 1964; Abramson, 1977).