Effects of Vowel Context on the Articulation of Stop Consonants

Movements of the lips and the mandible were studied by means of a stroboscopic motion picture techinque during the production of intervocalic velar (palatal) and alveolar stop consonants. Three subjects pronounced English words like veto, echo, cookie, okay, etc., in which significantly different labial articulations are required for the first vowel and the second vowel. A film speed of 60 frames/sec was employed for the experiment. Results indicate that during the closure period of nonlabial stops, the labial configuration changes considerably in anticipation of the following vowel. In echo, for example, the lips start to close during the production of the first vowel, and the most conspicuous change in their shape occurs during the closure period of /k/. In general, there is substantial disagreement between the movement of the lips and that of the mandible. Some details of the relation between the articulatory movement and the boundaries found in the sound spectrogram will be given. Implications concern...