Exploration of a treatment technique for prosodic disturbance following stroke

The effectiveness of a treatment technique targeting speech prosody was explored for an individual who had sustained a left hemisphere stroke. Acoustic and perceptual analyses suggested that reduced temporal variation of adjacent syllables (i.e. syllable isochronicity) contributed to impressions of reduced speech naturalness and monorhythmicity. Stress-patterning, therefore, was explored as a technique for increasing the temporal variation of adjacent syllables to improve rhythmicity and naturalness. Therapy tasks included three-syllable reiterant sequences and real words; treatment effects were measured for three-syllable words embedded in probe sentences. Visual and auditory feedback were provided in therapy using the Computerized Speech Lab. An objective, acoustic measure of syllable isochrony was also provided as feedback. Although the speaker was able to produce the targeted syllable isochrony measure in therapy tasks, performance did not generalize to three-syllable words in probe sentences. Potential explanations for why modifications in syllable isochronicity did not generalize beyond therapy tasks are discussed, as well as implications for using stress-patterning as a therapy technique with other individuals.