Effects of Cognitive Load on Vocal Motor Control: A Model-Based Analysis in Individuals With Hyperfunctional and Healthy Voices

Purpose: This study examined how cognitive load (CL) influences vocal motor control by integrating acoustic measures with biomechanical trajectories derived from a model-based approach. The aim was to determine whether speakers with vocal hyperfunction (VH) exhibit distinct modulation patterns in laryngeal control compared with healthy control (HC) speakers. Method: Recordings from female speakers (63 with VH and 62 HC speakers) performing a Stroop task were analyzed. Trajectories of fundamental frequency ( f o ) and sound pressure level (SPL) were extracted and used as inputs to a computational model that estimated cricothyroid ( a CT ) and thyroarytenoid ( a TA ) muscle activations, as well as subglottal pressure ( P S ). Acoustic and model-derived measures were segmented and analyzed using mixed-effects models. Results: Significant condition effects were found across acoustic and biomechanical features, with parallel patterns in f o – a CT and SPL – P S across segments and groups. No consistent differences were observed for a TA . The strongest effects occurred in SPL, which increased under CL, especially among speakers with VH, with P S showing a similar but weaker trend. For f o and a CT , opposite group patterns emerged at task onset: HC speakers showed slight decreases, whereas those with VH showed increases. Conclusions: The correspondence between acoustic and estimated biomechanical modulations under CL supports the utility of this model-based approach for physiologically interpretable inference of laryngeal motor behavior. Speakers with VH showed greater modulation of a CT and P S control, with no systematic changes in a TA , suggesting that arousal-related laryngeal tension primarily affects more superficial control dimension.