Abstract

The air pressure in the lungs, or more precisely, the subglottal air pressure, is the primary energy source in speech. Yet many clinicians avoid estimation of subglottal pressure in evaluating or treating patients because of the difficulty in measuring it. However, since its first reported use in 1973, the so-called Interpolation Method, in which the subglottal pressure during voiced speech is estimated from samples of intraoral pressure obtained during unvoiced stops, has achieved acceptance as a feasible and reliable method, if used properly. A new version of the method is described that uses a combination of interpolation and extrapolation to provide realtime subglottal pressure estimates for speech evaluation and biofeedback.