Talking About Tension: Distinguishing Primary Muscle Tension Dysphonia (MTD-1) From Compensatory Hyperfunction In Singing Training Vs. Clinical Settings

BACKGROUND INFORMATION: There is lacking consensus among voice professionals on the boundaries of compensatory hyperfunction (generically known as tension in vocal pedagogy) versus named disorders such as Primary Muscle Tension Dysphonia (MTD-1) for singers in training. Both are multifactorial phenomena involving habitual, excessive, non-volitional musculoskeletal constriction, neuromotor imbalance, and maladaptive learning disrupting proprioceptive feedback during voice production, resulting in inefficient and suboptimal phonatory output. (Van Houtte et al., 2011) Neither compensatory hyperfunction/singing tension nor the boundaries of MTD-1 in the speaking versus singing voice are well-represented or codified in voice science literature. As complex functional issues originating from multiple causes, diagnosing tension conditions in the singing voice is not standard clinical practice due to case-use specifications of singers. Further complicated are actively training singers, as building singing technique includes many co-influencing facets which may involve tension while efficient coordination is developed. Yet, in the singing voice training studio, tension issues manifesting as dysphonia have been posited as significant enough to merit a distinct label. (Chapman 2006)

OBJECTIVES: This collaborative mixed-methods study includes a multidisciplinary team of a singer/vocal pedagogue, otorhinolaryngologist, and speech-language pathologist. The scoping literature review closes the existing terminological gap surrounding tension in singers in training, while the according laryngoscopic and acoustical evaluation provides interventions for vocal pedagogues, voice clinicians, and singers themselves.

METHODS/DESIGN: First, convergences and divergences of compensatory hyperfunction and MTD-1 in singers are elucidated in a scoping literature review of 67 papers related to MTD-1 in singers (with 12 papers mentioning singing-specific MTD-1). Then, laryngoscopic and acoustic evaluations of 17 case study singer patients with reported tension disorders were conducted using metrics based on current diagnostic criteria of MTD-1 (Shembel et al., 2021; Han et al., 2023). Finally, the singer patient participants and their teachers were surveyed with open-ended interviews to corroborate the parametric findings.

RESULTS/CONCLUSIONS: A novel matrix distinguishing speaking and singing voice MTD-1 is proposed as an addition to the existing vocal hyperfunction theoretical framework (Hillman et al., 2020) Various archetypes and gradations of singing NPVH are outlined. Practical applications for implementation of a holistic diagnosis when working with singers in training who present with tension is offered.