Objective: This randomized controlled study aimed to explore the application of neuroscience principles to voice training, with the ultimate intent of enhancing the effectiveness of long-term vocal rehabilitation through early automatization. We examined an innovative assessment and treatment protocol that merges vocal technique with executive-attentional training, incorporating dual-task training in healthy singers.
Methods: Thirty participants underwent laryngostroboscopic examination to assess eligibility. Then subjects completed the Measures of Executive Attention (MEA) battery, followed by production of phrases, pitch glides, and singing for later acoustic analyses. Subjects were then randomized to a one-hour intervention involving training in phonatory respiration, voice projection, voice intensity and prosody control in speech and singing (N=15), or the same training under dual-task conditions invoking working memory in cognitive tasks (N=15), to achieve to “best voice possible.” Baseline voice tasks were then repeated. Outcome measures were MEA scores, and voice measures derived from Acoustic voice analysis: perturbation, harmonic to noise ratio (HNR), Acoustic Vocal Quality Index (AVQI), and Acoustic Breathiness Index (ABI). Participants also completed a post-intervention survey regarding their impressions about the benefits of their respective training.
Results: The experimental dual-task group demonstrated statistically greater improvements on all acoustic parameters, on average, compared to the control group. Experimental but not control subjects also showed improvements on MEA subtests of working memory, declarative memory, and sustained attention subtests, suggesting possible cognitive mechanisms for short-term voice changes in the experimental group. Finally, survey results indicated greater benefits from training for dual-task compared to control conditions.
Conclusions: Results are encouraging regarding the potential utility of dual-task models in singing training and pending further investigation, potentially in voice rehabilitation as well, towards more rapid automatization of newly acquired skills. This approach suggests a possible paradigm shift in voice training models, and even more boldly, models of perceptual-motor learning in general that have traditionally emphasized the late appearance of automaticity. The work establishes a foundation for future empirical studies rich with possibilities.