Floating ball voice therapy: Preliminary effects (Van Stan et al., 2024)

Purpose: Floating ball voice therapy (FBVT) is a voice-controlled virtual environment based on a common treatment component across multiple evidence-based therapies: improved vocal efficiency (target) via practicing voicing with modified resonance and airflow (ingredient). This study preliminarily tested FBVT’s effects on outcomes and the potential for its novel variability metrics to predict individual patient generalization.

Method: Ten patients with nonphonotraumatic vocal hyperfunction (NPVH) practiced FBVT for 10 days. Outcomes were assessed by a vocal efficiency ratio, a validated NPVH index, the patient-reported Voice-Related Quality of Life (V-RQOL), and forced-choice auditory judgments of overall severity. Exploration in early practice (Day 1) was estimated by how the patient’s two-dimensional variability (mean airflow and intensity) related to error (difference between the patient-produced and normative vocal efficiency ratio). Generalization from the game to spontaneous speech was evaluated using the validated NPVH index.

Results: Ten days of FBVT were associated with improved vocal efficiency (Cohen’s d = 1.3), NPVH index (d = −1.1), V-RQOL total score (d = 0.9), and overall severity (odds ratio = 2.5). Patients who generalized on Day 10 exhibited airflow/intensity exploration that was more aligned with the error gradient on Day 1 (d = 0.6–1.2).

Conclusions: A relatively small dosage of FBVT (i.e., 10 practice sessions) was associated with multiple improved voice therapy outcomes. The FBVT variability metrics on Practice Day 1 demonstrated strong potential to predict which patients generalized to connected speech. Future work can more thoroughly evaluate effects on outcomes and characterizing the quality of vocal exploration with a larger patient population.

Supplemental Material S1. Individual patient average values Error (pixels), T-Cost (pixels), N-Cost (pixels), and V-RQOL (arbitrary units) on days 1 and 10 of practice.

Supplemental Material S2. Individual NPVH indices (logit) for patients during early practice trials, late practice trials, and spontaneous speech during day 1, before day 10 practice, and after day 10 practice.

Van Stan, J. H., Hillman, R. E., Krusemark, C., Muise, J., Stadelman-Cohen, T., Mehta, D. D., & Sternad, D. (2024). Floating ball voice therapy: Preliminary effects on outcomes and predicting individual patient differences in generalization. Journal of Speech, Language, and Hearing Research, 67(10), 3521–3535. https://doi.org/10.1044/2024_JSLHR-23-00727