The effects of articulation errors on perceived nasality in speakers with repaired cleft lip and/or palate Kristin Louise Dattilo , University of Iowa Follow

[摘要] The purpose of this study was to further investigate the effects of articulation errors on perceptual ratings of nasality in speakers with repaired cleft palates, specifically looking at the effect of varying magnitudes of articulation errors and education on perception of nasality. A group of expert listeners, speech-language pathologists with significant clinical experience in the area of cleft palate and resonance disorders, first rated the articulatory proficiency and nasality of a number of utterances produced by children with repaired cleft palates, on separate 6-point scales. Their ratings were then used to categorize stimuli into a three-by-three matrix (mild, moderate, severe) using articulation deficit and nasality as the two dimensions of interest. Untrained listeners (undergraduates and graduate students in a speech-language pathology training program) were then asked to rate the level of nasality on a 1 (normal) to 6 (severe) scale. Listener group ratings were compared to each other and to the expert listeners. Significant differences (p=0.004) were found between the undergraduate and graduate students" ratings when compared to the expert listeners. Graduates, had lower inter- and intra-rater reliability compared to the undergraduates. For both undergraduates and graduates, the difference between their ratings and those of the expert listeners was significantly lower for stimuli with mild articulation errors compared to those with moderate (p<0.0001) and severe (p<0.0001) articulation errors. No significant differences (p=0.416) were found between difference scores for stimuli with moderate versus severe articulation errors. The results were interpreted to suggest that the magnitude, and perhaps type, of articulation errors affects perceived nasality, and that there are group differences between perceptual nasality ratings. These findings support the importance of articulation therapy for children with repaired cleft palates to both decrease articulation errors and decrease perceived nasality. Further, this study highlights the need for including awareness of this interaction in the training of speech-language pathologists in order for the "gold standard” of perceptual judgements to remain a valid and reliable measure.