Conversation Training Therapy: Let's Talk It Through

Estimating the Pathophysiology of Phonotraumatic Vocal Hyperfunction Using Ambulatory Data and a Computational Model

PURPOSE

This study uses a voice production model to estimate muscle activation levels and subglottal pressure (PS) in patients with phonotraumatic vocal hyperfunction (PVH), based on ambulatory measurements of sound pressure level (SPL) and spectral tilt (H1-H2). In addition, variations in these physiological parameters are evaluated with respect to different values of the Daily Phonotrauma Index (DPI).

METHOD

The study obtained ambulatory voice data from patients diagnosed with PVH and a matched control group. To infer physiological parameters, ambulatory data were mapped onto synthetic data generated by a physiologically relevant voice production model. Inverse mapping strategies involved selecting model simulations that represented ambulatory distributions using stochastic (random) sampling weighted by probability with which different vowels occur in English. A categorical approach assessed the relationship between different values of DPI and changes in estimated physiological parameters.

RESULTS

Results showed significant differences between the PVH and control groups in key parameters, including statistical moments of H1-H2, SPL, PS, and muscle activity of lateral cricoarytenoid (LCA) and cricothyroid (CT) muscles. Higher DPI values, reflecting more severe PVH, were associated with increased mean LCA activation and decreased LCA variability, along with decreased mean CT activation and increased median PS. These findings highlight the relationship between muscle activation patterns, PS, and the severity of vocal pathology as indicated by the DPI. It is hypothesized that a major driver of muscle activation and PS changes is the variation in maladaptive adjustments (vocal effort) when compensating for the presence of vocal pathology.

CONCLUSIONS

This study demonstrated that noninvasive ambulatory voice data could be used to drive a voice production modeling process, providing valuable insights into underlying physiological parameters associated with PVH. Future research will focus on refining the predictive power of the modeling process and exploring the implications of these findings in further delineating the etiology and pathophysiology of PVH, with the ultimate goal to develop improved methods for the prevention, diagnosis, and treatment of PVH.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.28352720.

Assessing Candidacy for Conversation Training Therapy: The Role of Patient Perception

OBJECTIVE

Voice therapy is the primary treatment modality for voice rehabilitation. Specific patient-ability factors beyond patient-characteristic factors (eg, disorder diagnosis, age, etc.), that influence individual patient responses to voice treatment remain largely unknown. The goal of the current study was to determine the relationship between patient-perceived improvements in both the sound and feel of voice during stimulability assessment and voice therapy outcomes.

STUDY DESIGN

Prospective Cohort study.

METHODS

This study was a single-arm, single-center, prospective study. Fifty patients with primary muscle tension dysphonia and benign vocal fold lesions were enrolled. Patients read the first four sentences of the Rainbow Passage and were asked if they experienced a change in the feel or sound of their voice following the stimulability prompt. Patients then completed four sessions of conversation training therapy (CTT) voice therapy and followed up one-week and three-months after their last therapy session, for a total of six time-points. Demographic data were collected at baseline, and voice handicap index 10 (VHI-10) scores were collected at each follow-up time-point. The primary exposure variables were CTT intervention and patient perception of voice change to stimulability probes. The primary outcome was change in VHI-10 score.

RESULTS

On average, VHI-10 scores improved for all participants following CTT treatment. All participants heard a change in the sound of voice with stimulability prompts. Descriptively, patients who reported a positive change in the feel of their voice after stimulability testing recovered faster (ie, experienced a sharper decline in VHI-10) compared to those who did not note a change in feel of voice during stimulability testing. However, the rate of change over time was not significantly different between groups.

CONCLUSION

Patient self-perception of a change in the sound and feel of voice in response to stimulability probes during initial evaluation is an important factor in treatment outcomes. Patients who perceive an improved feel of their voice production after stimulability probes may respond to voice therapy more quickly.