Intensive treatment of dysarthria in two adults with Down syndrome.

Objective: This study investigated the impact of an established behavioural dysarthria treatment on acoustic and perceptual measures of speech in two adults with Down syndrome (DS) and dysarthria to obtain preliminary measures of treatment effect, effect size and treatment feasibility.

Methods: A single-subject A-B-A experimental design was used to measure the effects of the Lee Silverman Voice treatment (LSVT®) on speech in two adults with DS and dysarthria. Dependent measures included vocal sound pressure level (dB SPL), phonatory stability and listener intelligibility scores.

Results: Statistically significant improvements (p < 0.05) in vocal dB SPL and phonatory stability were present following treatment in both participants. Speech intelligibility scores improved in one of the two participants.

Conclusions: These data suggest that people with DS and dysarthria can respond positively to intensive speech treatment such as LSVT. Further investigations are needed to develop speech treatments specific to DS.