The intelligibility of time-domain-edited esophageal speech

The intelligibility of esophageal speech has been shown to be significantly lower than that of normal laryngeal speech. The current study investigated the possibility of enhancing the intelligibility of esophageal speech by manipulating samples in the time domain. Specifically, injection noises and nonphrasal pauses were digitally edited from the speech samples of 5 esophageal talkers. Twenty-five sentences were selected and edited in the time domain and presented to 15 naive listeners who were instructed to write down the words that they heard. The percentage of correct words heard for each sentence was determined and compared across listeners, sentences, and talkers. The overall effect of the editing was a small but significant gain in the intelligibility of the esophageal speech. The improvement in intelligibility, however, depended on the individual talker, the speech material, and the number of editing changes made to a particular sample.