Changes in vocal loudness following intensive voice treatment (LSVT) in individuals with Parkinson's disease: a comparison with untreated patients and normal age-matched controls

Mov Disord. 2001 Jan;16(1):79-83. doi: 10.1002/1531-8257(200101)16:1<79::aid-mds1013>;2-h.


This study assessed the impact of the Lee Silverman Voice Treatment (LSVT) on vocal loudness [sound pressure level (SPL)] in a group of dysarthric individuals with idiopathic Parkinson's disease (IPD). Pre- to post-treatment changes in SPL in the treated group were compared with changes in voice SPL during the same time in two control groups: individuals with IPD not treated with the LSVT and in non-disordered individuals, age-matched to the patients. All subjects produced the same voice and speech tasks--sustaining vowel phonation, reading the "Rainbow Passage," producing a short monologue, and describing a picture. These tasks were recorded at three different occasions: just prior to treatment, just after treatment, and 6 months following treatment. The individuals treated with LSVT increased voice SPL from baseline to post-treatment by an average of 8 dB and from baseline to 6 months follow-up by an average of 6 dB. These changes were statistically significant and perceptibly audible. No significant changes in SPL were observed in the control groups during the time corresponding to the treatment and follow-up. Differences in SPL between the treated and untreated patients at post-treatment and follow-up were statistically significant for all voice and speech tasks. These findings, along with others, provide additional support for the efficacy of the LSVT.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Female
  • Humans
  • Male
  • Parkinson Disease / complications*
  • Severity of Illness Index
  • Treatment Outcome
  • Voice Disorders / diagnosis
  • Voice Disorders / etiology*
  • Voice Disorders / therapy*
  • Voice Quality
  • Voice Training*