Tremor frequency characteristics in Parkinson's disease under resting-state and stress-state conditions

Abstract Tremor characteristics—amplitude and frequency components—are primary quantitative clinical factors for diagnosis and monitoring of tremors. Few studies have investigated how different patient's conditions affect tremor frequency characteristics in Parkinson's disease (PD). Here, we analyzed tremor characteristics under resting-state and stress-state conditions. Tremor was recorded using an accelerometer on the finger, under resting-state and stress-state (calculation task) conditions, during rest tremor and postural tremor. The changes of peak power, peak frequency, mean frequency, and distribution of power spectral density (PSD) of tremor were evaluated across conditions. Patients whose tremors were considered more than “mild” were selected, for both rest (n = 67) and postural (n = 25) tremor. Stress resulted in both greater peak powers and higher peak frequencies for rest tremor (p