The role of linguistic and indexical information in improved recognition of dysarthric speech

• Published in: The Journal of the Acoustical Society of America 2011-10, Vol.130 (4_Supplement), p.2447-2447
• Main Authors: Borrie, S. A., McAuliffe, M. J., Liss, J. M., O.Beirne, G. A., Anderson, T.
• Format: Article
• Language: English
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.3654822

This investigation examined perceptual learning of dysarthric speech. Forty listeners were randomly assigned to one of two identification training tasks, aimed at highlighting either the linguistic (word identification task) or indexical (speaker identification task) properties of the neurologically degraded signal. Immediately following familiarization, all listeners completed an identical phrase transcription task. Analysis of post-training listener transcripts revealed remarkably similar intelligibility improvements for listeners trained to attend either the linguistic or the indexical properties of the signal. Perceptual learning effects were also evaluated with regard to underlying error patterns indicative of segmental and suprasegmental processing. Comparisons revealed no significant difference at either level of perceptual processing for the two training groups. The findings of this study suggest that elements within both the linguistic and indexical properties of the dysarthric signal are learnable and interact to promote improved processing of this type and severity of speech degradation. Furthermore, error pattern analysis indicates that similar cognitive–perceptual mechanisms may underlie the processing of indexical and linguistic information. Thus, the current study extends support for the development of a model of perceptual processing in which the learning of indexical properties is encoded and retained alongside linguistic properties of the signal.