Speed of Pitch Change in People with Parkinson’s Disease: A Pilot Study

Objective. To examine laryngeal maximum performance through a novel pitch diadochokinetic (DDK) task in people with Parkinson’s disease (PD) and healthy controls. Methods. This exploratory pilot study included a total of eight people with PD (seven male and one female) and eight healthy controls. Participants were instructed to rapidly transition or alternate between a chosen comfortable low and high pitch and were instructed to complete the task as a pitch glide. An Auditory Sawtooth Waveform Inspired Pitch Estimator-Prime model was used to first extract the pitch contour and then a customized MATLAB algorithm was used to compute and derive measures of pitch range and pitch slope. Results. Pitch range and slope were reduced in some participants with PD. Effects of age and disease duration were observed in people with PD: reductions in both pitch measures with increase in age and disease duration. Conclusions. A novel pitch DDK task may supplement the conventional laryngeal DDK task in the evaluation and treatment of motor speech and voice disorders. Individual variability analysis may provide specific diagnostic and therapeutic insights for people with PD.