Disordered speech as a testing ground for listener learning and adaptation.

Abstract

Speech production disorders arise from a wide variety of anatomical defects, neurological injury, and disease. Depending on the etiology, the speech manifestations may be quite regularized—in the same way that a foreign accent presents consistently—or highly variable with unpredictable speech interruption and degradation. Indeed, even within an individual speaker, one will find both relatively consistent and variable aspects of speech abnormality. A growing body of literature shows that listeners enjoy intelligibility gains with just brief auditory exposure to disordered speech that is accompanied by lexical feedback, and with repeated unsupervised exposures. These benefits have been shown to be both talker-specific and applicable to groups of people who presumably share relevant acoustic-perceptual speech features. While many of these studies have been designed with an eye toward clinical and communicative implications, there is much to be learned about the mechanisms underlying these perceptual improvements with naturally impoverished speech. The purpose of this presentation is to describe the use of clinical populations as a testing ground for hypotheses of listener learning and adaptation. Speech production disorders particularly lend themselves to the study of episodic memory, rhythmic expectancy, and talker-specific versus talker-general effects. [Work supported by NIDCD, NIH.]