The Lombard effect on alaryngeal speech

The need to train alaryngeal speakers to use increased vocal intensity has been noted in the literature. One untested technique is to evoke an intensity increase by applying masking noise to the ears of the talker. The purpose of this study was to investigate the Lombard effect on the speech of esophageal talkers, artificial larynx users, and normal speakers. The subjects read aloud a variety of materials first in quiet then while being subjected to 100 dB SPL noise delivered through earphones. The resulting sound pressure values were obtained by measuring the peak values of all syllables spoken by each talker. The results indicated that the esophageal talkers produced the highest intensity increase in the noise condition followed by the normal talkers and the artificial larynx talkers. Coarticulatory and duration effects on alaryngeal and normal speech are also reported. Clinical implications are discussed.