title: Lombard's effect's implication in intensity, fundamental frequency and stability on the voice of individuals with Parkinson's disease.
abstract: Parkinson's disease affects the central nervous system resulting in voice quality alterations. It is typically resistant to drug therapy and often persists despite extensive behavioural speech and language therapy. Previous findings show that masking noise will produce a consistent increase in voice intensity in most normal individuals (Lombard's effect).
  
  
  OBJECTIVE
  we evaluated Lombard's effect's implication in intensity, fundamental frequency and stability on the voice of individuals with Parkinson's disease (N=17).
  
  
  METHODS
  through acoustic analysis, we evaluated intensity alterations and fundamental frequency, before and after white masking noise 40, 70 and 90 dBSL intensities, as well as variations during each vocalization and compared with a control group (N=16).
  
  
  RESULTS
  voice intensity varied according to masking intensity, tending to non-linear increases in both groups and gender. Fundamental frequency varied, tending to non-linear increase in both groups and gender. Improvement stability occurred in fundamental frequency and vocal intensity.
  
  
  CONCLUSIONS
  Lombard's effect increased intensity, fundamental frequency and improves voice stability on these patients.
  
  
  METHODS
  clinical and experimental.
authors: School of Medical Sciences, Santa Casa de São Paulo.
authors: Araken
authors: A
authors: Quedas
authors: André de Campos
authors: Ade C
authors: Duprat
authors: Gisele
authors: G
authors: Gasparini
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008144:Loudness Perception / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications* / Q000503:physiopathology; D013018:Sound Spectrography; D013061:Speech Acoustics; D013068:Speech Production Measurement; D014832:Voice Disorders / Q000209:etiology* / Q000503:physiopathology