Aperiodic subthalamic activity underlies sleep-wake modulation of beta power during conventional and adaptive deep brain stimulation in Parkinson’s disease

ABSTRACT Subthalamic local field potential (STN-LFP) activity within patient-specific beta frequency ranges is an established biomarker for adaptive deep brain stimulation (aDBS) in Parkinson’s disease (PD). While beta power correlates with akinetic-rigid symptoms, it is also modulated by physiological states such as sleep, highlighting the importance of understanding state-dependent spectral dynamics for adaptive stimulation. We continuously recorded STN-LFP spectra in ten PD patients over two weeks in both conventional and adaptive DBS. We show that sleep-related reductions in beta power occur independently of stimulation mode and are primarily associated with broadband aperiodic spectral changes across both low and high beta bands rather than periodic beta oscillations. These findings support the integration of aperiodic spectral features into future adaptive neuromodulation algorithms to improve biomarker specificity and optimize aDBS in PD.