Semantic context and speech intelligibility

Using the mutuality model as a framework, the present research project investigates the influence of syntactic and semantic context on the speech intelligibility of dysarthric speakers. Recordings were made of eight flaccid dysarthric individuals reading words and sentences from the Speech Perception in Noise (SPIN) Test. Ninety-six inexperienced listeners orthographically transcribed the recordings under four conditions: word transcription-no semantic context; word transcription with semantic context; sentence transcription-no semantic context; and sentence transcription with semantic context. A three-way ANOVA with a nested factor was used to analyze the data. The results revealed significant gains in the speech intelligibility scores of the dysarthric speakers when listeners were presented syntactic and semantic context cues. Significant interactions between semantic context and syntactic context, and syntactic context and severity of dysarthria were also recorded. The additive effects of combining both syntactic and semantic context predicted by the mutuality model were not confirmed. These results suggest that the speech intelligibility of flaccid dysarthric speakers can be significantly improved, in light of a distorted signal, by increasing listener knowledge through syntactic and semantic context. Speech intelligibility tasks that take these factors into account may provide a more realistic measure of overall functional communication