Neck Skin's Mechanical Properties Affect Voice Assessment Using Surface Accelerometers

Neck-surface accelerometers are widely used for non-invasive assessment of phonation and vocal fold vibration, offering insights into voice health and dysphonia. However, the accuracy of these measurements relies on the assumption that the skin-sensor interface is consistent across individuals. This study addresses how the mechanical properties of the anterior cervical skin specifically impact the acceleration levels recorded during voice production.

The study revealed a significant correlation between skin mechanical properties and recorded skin acceleration levels. Specifically, increased skin stiffness was associated with higher skin acceleration amplitudes during phonation (r = 0.72, p < 0.001). Furthermore, skin thickness showed a moderate inverse correlation with acceleration levels (r = -0.45, p = 0.012), suggesting thicker skin might dampen surface vibrations. These findings indicate that variations in anterior cervical skin mechanics can introduce substantial variability into accelerometer-based voice assessments, potentially leading to misinterpretations of vocal function. The most critical finding was that participants with lower skin elasticity exhibited a 25% to 30% increase in peak skin acceleration levels compared to those with higher elasticity, particularly at higher fundamental frequencies.