Some effects of text coherence on the comprehension of natural and synthetic speech
James V. Ralston, Scott E. Lively, David B. Pisoni · The Journal of the Acoustical Society of America · 1991
Subjects listened to naturally and synthetically produced (Votrax Type-n-Talk) passages of varying levels of difficulty in a sentence-by-sentence listening time task. Listeners controlled the intersentence interval while listening to passages presented in their normal sentence order or in a random sentence order. Subjects listening to Votrax speech had significantly longer intersentence response times in both the normally ordered and the randomly ordered sentence conditions. Furthermore, in a recognition test given after each passage, subjects' performance varied as a function of speech type, passage difficulty, and recognition question type. Subjects listening to synthetic speech responded more accurately to word recognition questions than to proposition recognition questions. Listeners who heard natural speech, in contrast, demonstrated better proposition recognition performance. The results indicate that listeners who heard synthetic speech attended more closely to the acoustic-phonetic input than to the propositions of the passages. The results are discussed in terms of a limited capacity attentional mechanism. [Work supported by NSF IRI 86-17847.]