title: Acoustics of clear speech: effect of instruction.
abstract: OBJECTIVE
  This study investigated how different instructions for eliciting clear speech affected selected acoustic measures of speech.
  
  
  METHODS
  Twelve speakers were audio-recorded reading 18 different sentences from the Assessment of Intelligibility of Dysarthric Speech (  Yorkston & Beukelman, 1984). Sentences were produced in habitual, clear, hearing impaired, and overenunciate conditions. A variety of acoustic measures were obtained.
  
  
  RESULTS
  Relative to habitual, the clear, hearing impaired, and overenunciate conditions were associated with different magnitudes of acoustic change for measures of vowel production, speech timing, and vocal intensity. The overenunciate condition tended to yield the greatest magnitude of change in vowel spectral measures and speech timing, followed by the hearing impaired and clear conditions. SPL tended to be the greatest in the hearing impaired condition for half of the speakers studied.
  
  
  CONCLUSIONS
  Different instructions for eliciting clear speech yielded acoustic adjustments of varying magnitude. Results have implications for direct comparison of studies using different instructions for eliciting clear speech. Results also have implications for optimizing clear speech training programs.
authors.affiliation: University at Buffalo, NY, USA. jkyun@buffalo.edu
authors.forename: Jennifer
authors.initials: J
authors.lastname: Lam
authors.forename: Kris
authors.initials: K
authors.lastname: Tjaden
authors.forename: Greg
authors.initials: G
authors.lastname: Wilding
mesh_terms: D000293:Adolescent; D000328:Adult; D003142:Communication; D004401:Dysarthria / Q000534:rehabilitation; D005260:Female; D006185:Habituation, Psychophysiologic; D034381:Hearing Loss; D006801:Humans; D008297:Male; D010699:Phonation; D010700:Phonetics; D011571:Psychoacoustics; D013060:Speech; D013061:Speech Acoustics; D013062:Speech Articulation Tests; D013065:Speech Intelligibility; D013070:Speech Therapy / Q000379:methods*; D055815:Young Adult