Investigation of the Timing of Velar Movements during Speech

High-speed cinefluorographic films were taken of four normal subjects speaking English sentences containing various combinations of nasal consonants (N), consonants (C), and vowels (V) at normal speaking levels and rates of production. Word and syllable boundaries were designed to fall across the sequences in various ways. From frame-by-frame tracings, measures of velar movement and velopharyngeal opening were made. Results indicate extensive anticipatory coarticulation of velar movement toward velopharyngeal opening in CVN and CVVN sequences such that velar movement toward opening began during the approach to the initial vowel in all cases and some velopharyngeal opening was observed on all vowels. For NC and NCN sequences, velar movement toward closure for the consonant usually began during the preceding nasal such that some velar closure was observed during all plosive and fricative consonants used. These results directly contradict the hypothesis that a CV-type syllable is the minimal unit of coarticulation and production. The data are consistent with the predictions of a model which assumes phone-sized input unit and which incorporates a “look ahead” mechanism whereby an articulatory feature can be systematically anticipated prior to the occurrence of the phone with which that feature is associated.