Voice-onset time

In phonetics, voice-onset time (VOT) is a feature of the production of stop consonants. It is defined as the length of time that passes between the release of a stop consonant and the onset of voicing, the vibration of the vocal folds, or, according to other authors, periodicity. Some authors allow negative values to mark voicing that begins during the period of articulatory closure for the consonant and continues in the release, for those unaspirated voiced stops in which there is no voicing present at the instant of articulatory closure.

History

The concept of voice-onset time can be traced back as far as in the 19th century, when Adjarian (1899: 119) studied the Armenian stops, and characterized them by the "relation qui existe entre deux moments : celui où la consonne éclate par l'effet de l'expulsion de l'air hors de la bouche, ou explosion, et celui où le larynx entre en vibration" (relation that exists between two moments: the one when the consonant bursts when the air is released out of the mouth, or explosion, and the one when larynx starts vibrating). However, the concept will become "popular" only in the 1960s, in a context described by Lin & Wang (2011: 514): "At that time, there was an ongoing debate about which phonetic attribute would allow voiced and voiceless stops to be effectively distinguished. For instance, voicing, aspiration, and articulatory force were some of the attributes being studied regularly. In English, "voicing" can successfully separate /b, d, ɡ/ from /p, t, k/ when stops are at word-medial positions, but this is not always true for word-initial stops. Strictly speaking, word-initial voiced stops /b, d, ɡ/ are only partially voiced, and sometimes are even voiceless." The concept of VOT will finally acquire its name in the famous study of Lisker & Abramson (1964).