Intraoral Air Pressure during Vocal and Whispered Speech

Abstract

Intraoral air pressure (P10) has been used to distinguish speech production parameters such as voicing and, to a lesser degree, place of articulation. At least four physiological mechanisms have been hypothesized to account for the variations in air pressure associated with consonant production. In this study, P10 was measured during whispered and vocal speech to examine the nature of the pressure variations found in voiced and voiceless consonants in the presence and absence of glottal closure and increased air volume. Subjects read a variety of sentences, CV syllables, and CV syllables in carrier phrases. From these protocols, intraoral air pressures were measured for consonants /p,b,m,t,d,n,s,z/ in initial, medial, and final phonetic positions. In one experimental condition, both P10 and expired air volume were measured. Results indicate that the vocal P10 is in agreement with previous data. For the whispered samples, there was little difference in peak pressure between the voiced and voiceless plosives; nasals showed lowest peak values. Whispered samples did not always produce the highest pressures for a given consonant; however, expelled air volume was always greater for the whispered samples.