title: Speech Prosody Across Stimulus Types for Individuals with Parkinson's Disease.
abstract: BACKGROUND
  Up to 89% of the individuals with Parkinson's disease (PD) experience speech problem over the course of the disease. Speech prosody and intelligibility are two of the most affected areas in hypokinetic dysarthria. However, assessment of these areas could potentially be problematic as speech prosody and intelligibility could be affected by the type of speech materials employed.
  
  
  OBJECTIVE
  To comparatively explore the effects of different types of speech stimulus on speech prosody and intelligibility in PD speakers.
  
  
  METHODS
  Speech prosody and intelligibility of two groups of individuals with varying degree of dysarthria resulting from PD was compared to that of a group of control speakers using sentence reading, passage reading and monologue. Acoustic analysis including measures on fundamental frequency (F0), intensity and speech rate was used to form a prosodic profile for each individual. Speech intelligibility was measured for the speakers with dysarthria using direct magnitude estimation.
  
  
  RESULTS
  Difference in F0 variability between the speakers with dysarthria and control speakers was only observed in sentence reading task. Difference in the average intensity level was observed for speakers with mild dysarthria to that of the control speakers. Additionally, there were stimulus effect on both intelligibility and prosodic profile.
  
  
  CONCLUSIONS
  The prosodic profile of PD speakers was different from that of the control speakers in the more structured task, and lower intelligibility was found in less structured task. This highlighted the value of both structured and natural stimulus to evaluate speech production in PD speakers.
authors.affiliation: Clinical Audiology, Speech and Language Research Centre (CASL), Queen Margaret University, Edinburgh, UK.
authors.forename: Joan
authors.initials: J
authors.lastname: K-Y Ma
authors.affiliation: Division of Neurodegenerative Diseases, Department of Neurology, Technische Universität Dresden, Dresden, Germany.|German Centre for Neurodegenerative Disease (DZNE), Dresden, Germany.
authors.forename: Christine B
authors.initials: CB
authors.lastname: Schneider
authors.affiliation: Institute of Acoustics and Speech Communication, Technische Universität Dresden, Dresden, Germany.
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Hoffmann
authors.affiliation: Division of Neurodegenerative Diseases, Department of Neurology, Technische Universität Dresden, Dresden, Germany.|German Centre for Neurodegenerative Disease (DZNE), Dresden, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Storch
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000368:Aged; D004401:Dysarthria / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications / Q000503:physiopathology*; D011932:Reading; D013060:Speech / Q000502:physiology*; D013068:Speech Production Measurement
keywords: Hypokinetic dysarthria; Parkinson’s disease; intelligibility; prosody; stimulus effect