Consonant Acoustics in Parkinson's Disease and Multiple Sclerosis: Comparison of Clear and Loud Speaking Conditions Purpose The impact of clear speech or an increased vocal intensity on consonant spectra was investigated for speakers with mild dysarthria secondary to multiple sclerosis or Parkinson's disease and healthy controls. Method Sentences were read in habitual, clear, and loud conditions. Spectral moment coefficients were obtained for word-initial ... Research Article
Research Article  |   June 22, 2017
Consonant Acoustics in Parkinson's Disease and Multiple Sclerosis: Comparison of Clear and Loud Speaking Conditions
 
Author Affiliations & Notes
  • Kris Tjaden
    Department of Communicative Disorders and Sciences, University at Buffalo, NY
  • Vincent Martel-Sauvageau
    Rehabilitation Department, Laval University, Quebec City, Canada
  • Disclosure: The authors have declared that no competing interests existed at the time of publication.
    Disclosure: The authors have declared that no competing interests existed at the time of publication. ×
  • Correspondence to Kris Tjaden: tjaden@buffalo.edu
  • Editor: Nancy Solomon
    Editor: Nancy Solomon×
  • Associate Editor: Christopher Dromey
    Associate Editor: Christopher Dromey×
Article Information
Hearing & Speech Perception / Acoustics / Special Populations / Older Adults & Aging / Speech, Voice & Prosody / Special Issue: Selected Papers From the 2016 Conference on Motor Speech—Clinical Science and Implications / Research Articles
Research Article   |   June 22, 2017
Consonant Acoustics in Parkinson's Disease and Multiple Sclerosis: Comparison of Clear and Loud Speaking Conditions
American Journal of Speech-Language Pathology, June 2017, Vol. 26, 569-582. doi:10.1044/2017_AJSLP-16-0090
History: Received June 6, 2016 , Revised August 9, 2016 , Accepted September 19, 2016
 
American Journal of Speech-Language Pathology, June 2017, Vol. 26, 569-582. doi:10.1044/2017_AJSLP-16-0090
History: Received June 6, 2016; Revised August 9, 2016; Accepted September 19, 2016

Purpose The impact of clear speech or an increased vocal intensity on consonant spectra was investigated for speakers with mild dysarthria secondary to multiple sclerosis or Parkinson's disease and healthy controls.

Method Sentences were read in habitual, clear, and loud conditions. Spectral moment coefficients were obtained for word-initial and word-medial /s/, /ʃ/, /t/, and /k/. Global production differences among conditions were confirmed with measures of vocal intensity and articulation rate.

Results Static or slice-in-time first moments (M1) for loud differed most frequently from habitual, but neither loud nor clear enhanced M1 contrast for consonant pairs. In several instances, the clear and loud conditions yielded stable or nonvarying fricative M1 time histories. Spectral contrast was reduced for word-medial versus word-initial consonant pairs.

Conclusion The finding that the loud and especially clear condition yielded fairly subtle changes in consonant spectra suggests these global techniques may minimally enhance consonant segmental production or contrast in mild dysarthria. The robust effect of word position on consonant spectra indicates that this variable deserves consideration in future studies. Future research also is needed to investigate how or whether consonant production bears on the improved intelligibility previously reported for these global dysarthria treatment techniques.

Acknowledgment
We thank Caroline Brown for her assistance with various aspects of the project.
Order a Subscription
Pay Per View
Entire American Journal of Speech-Language Pathology content & archive
24-hour access
This Article
24-hour access