The impact of speech supplementation on the intelligibility of speakers with traumatic brain injury

By D.R. Beukelman, S. Fager, J. Logemann, and H. Baum


The purpose of this study was to investigate the differences in speech intelligibility (percent of words understood) for sentences among (a) habitual speech, (b) "clear speech", (c) alphabet supplemented speech, (d) topic supplemented speech, (e) alphabet supplementation superimposed on habitual speech. Eight persons with severe dysarthria following traumatic brain injury participated in this project. Speakers were video recorded as they produced 10 Hearing In Noise Test sentences under each of the condition. Five listeners transcribed the speech samples for the 5 experimental conditions. Supplemented speech yielded higher sentence intelligibility scores than habitual speech. Alphabet supplemented speech yielded higher sentence intelligibility scores than topic supplemented speech. "Clear speech" yielded slightly higher scores than habitual speech for some participants.