Changes to articulation following LSVT(R) and traditional dysarthria therapy in non-progressive dysarthria

The present study aimed to evaluate the effects of the Lee Silverman Voice Treatment (LSVT(R)) on acoustic and perceptual measures of articulation in non-progressive dysarthria in comparison to traditional dysarthria therapy. The study involved 26 individuals with non-progressive dysarthria who were randomly allocated to receive either LSVT(R) or traditional dysarthria therapy (TRAD), both of which were administered for 16 hourly sessions over 4 weeks. Participants' speech samples were collected over a total of six testing sessions during three assessment phases: (1) prior to treatment, (2) immediately post-treatment, and (3) 6 months post-treatment (FU). Speech samples were analysed perceptually to determine articulatory precision and intelligibility as well as acoustically using vowel space (and vowel formant measures) and first moment differences. Results revealed short and long-term significant increases in vowel space area following LSVT(R). Significantly increased intelligibility was also found at FU in the LSVT(R) group. No significant differences between groups for any variables were found. The study reveals that LSVT(R) may be a suitable treatment option for improving vowel articulation and subsequent intelligibility in some individuals with non-progressive dysarthria.