Singing-Based Interventions for Treating Hypokinetic Dysarthria in Parkinson's Disease: A Systematic Review

Parkinson's disease (PD) progressively affects motor functions, often resulting in hypokinetic dysarthria, characterized by reduced speech articulation and vocal intensity. Over the last few decades, singing-based interventions have demonstrated potential therapeutic benefits for treating neurological speech disorders. To review the effectiveness of singing-based interventions in treating hypokinetic dysarthria, articles were identified based on a search across MEDLINE, PubMed, Scopus, ScienceDirect, and Web of Science. After being independently screened by the authors, the information was reviewed and extracted from articles written in English and Spanish investigating the potential benefits of music interventions in people living with PD. A total of 23 studies, out of 742 screened, involving 381 participants, were included. The majority of the studies were deemed of low quality due to the risk of bias from small sample sizes, lack of randomization, absence of control groups, and heterogeneous samples resulting from the progression of the disease. Overall, the review revealed that singing-based interventions improve phonation, prosody, and respiratory control, particularly those that incorporate group singing and vocal exercises based on speech-language pathology principles and techniques, such as the Lee Silverman voice treatment (LSVT). Findings suggest that singing-based interventions, when combined with and guided by LSVT principles, may maximize therapeutic benefits on speech quality in people living with PD. Additionally, several studies reported positive effects on emotional well-being and quality of life, reinforcing their potential psychosocial benefits. However, more studies with greater methodological rigor and long-term follow-up are needed to confirm these effects and establish more standardized intervention protocols.