Understanding dysrhythmic speech: When rhythm does not matter and learning does not happen

Abstract

A positive relationship between rhythm perception and improved understanding of a naturally dysrhythmic speech signal, ataxic dysarthria, has been previously reported [Borrie, Lansford, and Barrett. (2017). J. Speech Lang. Hear. Res. 60, 3110-3117]. The current follow-on investigation suggests that this relationship depends on the nature of the dysrhythmia. When the corrupted rhythm cues are relatively predictable, affording some learnable acoustic regularity, the relationship is replicated. However, this relationship is nonexistent, along with any intelligibility improvements, when the corrupted rhythm cues are unpredictable. Findings highlight a key role for rhythm perception and distributional regularities in adaptation to dysrhythmic speech.

Fig. 1.

(Color online) Average rhythm perception scores for listeners in the hyperkinetic-unpredictable and hypokinetic-predictable speech conditions.

Fig. 2.

(Color online) Average pretest (initial intelligibility) and posttest intelligibility scores for listeners in the hyperkinetic-unpredictable and hypokinetic-predictable speech conditions. Intelligibility improvement is reflected in the slope of the connecting line.