Voice Onset Time (VOT) is a term in phonetics that refers to the temporal gap between the release of a plosive consonant (e.g., /p/, /t/, /k/) and the onset of voicing (vibration of the vocal cords) during speech production. VOT is a crucial parameter used to categorize plosives into two main categories: Voiced and Voiceless.
In the case of voiced consonants, such as /b/, /d/, and /g/, the speaker initiates voicing before or during the release of the occlusion, resulting in a negative VOT value. This means that the vibration of the vocal cords is detected before the airflow is completely released. Examples include the word "bead" (/biːd/), where the /b/ sound is produced with a short period of voicing before the release of the lips.
On the other hand, voiceless plosives like /p/, /t/, and /k/ have a positive VOT value. Here, the vocal cords start vibrating after the release of the occlusion or when the airflow begins, resulting in voicelessness. For instance, in the word "peat" (/piːt/), the /p/ sound is produced with a discernible delay before the vocal cords start vibrating.
The Voiced-Voiceless distinction based on VOT is a vital distinction in various languages, as it affects the meaning of words. Additionally, VOT duration can vary across languages and dialects due to phonetic differences. VOT measurements play a significant role in phonetic research, language acquisition studies, and clinical speech pathology to analyze speech production, perception, and disorders.
