Auditory vs visual speech timing cues as external rate control to enhance verbal intelligibility in mixed spastic ataxic dysarthric speakers: a pilot study

Abstract

Metronome, singing, and board pacing were used as external rate control techniques for the purpose of comparing the effectiveness of auditory and visual speech timing cues for reducing speech rate and increasing intelligibility in three traumatically brain injured mixed spastic-ataxic dysarthric speakers. A single system design with baseline reversal (ABACAD) was used in this preliminary investigation. Results demonstrated statistically significant (p < 0.05) changes in increased speech intelligibility during all three pacing conditions for the two more involved subjects. Differences between treatment conditions were not statistically significant. However, auditory metronome cuing showed the best results for the two subjects who benefited from rate control. Lower baseline intelligibility was strongly correlated with higher benefit from rate control. Furthermore, the two auditory rhythmic pacing conditions exhibited a close synthronization effect between the frequency rate of the cue and speech rate. Significant correlation coefficients between decreased speech rate and increased intelligibility were only found for the two more involved subjects. These findings suggested a differential benefit of slowing speech rate to improve intelligibility contingent upon severity of speech deficits.

The discovery of human auditory–motor entrainment and its role in the development of neurologic music therapy

“…Recent findings in aphasia rehabilitation suggest that the rhythmic component in Melodic Intonation Therapy might even be as important as the activation of intact righthemispheric speech circuitry through singing (Stahl et al, 2011). Rate control via auditory rhythmic cues has been successfully applied to fluency disorders (e.g., stuttering, cluttering), as well improvements in intelligibility in dysarthria (Lansford et al, 2011;Pilon et al, 1998;Thaut et al, 2001;Van Nueffelen et al, 2009. NMT has an excellent standardized repertoire of evidence-based techniques for speech and language training based on rhythmic entrainment mechanisms (Thaut and Hoemberg, 2014).…”

The Effect of Aging and Synthetic Topic Cues on the Intelligibility of Dysarthric Speech

“…Traditional strategies to enhance intelligibility, such as rate control (Hammen, Yorkston, & Dowden, 1991;Linebaugh & Wolfe, 1984;Pilon, McIntosh, & Thaut, 1998;Turner, Tjaden, & Weismer, 1995) and articulation therapy (Mitsumoto et al, 1998), may prove useful in the early stages of speech decline, but in later stages strategies that focus on the speech signal may not be sufficient. At this stage, the goal of intervention is to optimize communication with the minimum amount of effort on the part of the person with ALS.…”

Effect of Rate Control on Speech Production and Intelligibility in Dysarthria

“…This study revealed that apart from individuals with a hypokinetic and ataxic dysarthria, individuals with UUMND and mixed dysarthria may also benefit from rate control. Two other studies reported a positive effect of rate control in a total of 6 individuals with mixed dysarthria [12,18] . These results suggest that the positive effect of rate control is not restricted to hypokinetic and ataxic dysarthria and that various types of dysarthria may benefit from rate control.…”