Control of pharyngeal cavity size for English voiced and voiceless stops

This study reports on pharyngeal cavity size change mechanisms associated with voiced−voiceless stop contrast in English. Electromyographic recordings were obtained from pharyngeal and infrahyoid muscles of three speakers, using bipolar, hooked−wire electrodes. The EMG potentials were sampled and averaged under computer control. The utterances sampled were 27 pairs of nonsense disyllables that contrasted only in the voicing of one stop consonant. All the English stop cognate pairs were included. Two modes of expanding the pharynx for voiced stops are proposed, each applying to a different group of muscles; an ’’active’’ mode, requiring increased muscle activity to expand the pharynx; and a ’’passive’’ mode, requiring suppression of muscle activity to expand the pharynx. The data reveal different patterns of use of the two expansion modes for the three subjects. The results are discussed in terms of current phonological theory. Subject Classification: 70.20.