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bioRxiv · 10.1101/2025.05.07.652676

A protective role of REM sleep in the pathological basal ganglia-cortical circuit of Parkinson's disease

Zhang, J.-X.·Smyth, C.·Anjum, M. F.·Leng, Y.·Krystal, A. D.·Starr, P. A.·Little, S.
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Abstract

Sleep disturbances have been shown to be intimately and bidirectionally related to disease progression across a wide range of neurodegenerative disorders including Parkinsons disease (PD) and Alzheimers disease. However, the precise neurophysiological mechanisms relating abnormal sleep to aberrant daytime network activity that accelerates disease progression has yet to be determined. We collected chronic, multi-night (n=40), intracranial cortico-basal recordings during sleep from a cohort of patients with PD along with paired polysomnography and morning self-reports. This revealed that longer duration (and shorter latency) of rapid eye movement (REM) sleep predicted reduced daytime resting beta (13-30 Hz) activity and cortico-basal functional and effective connectivity, features established to be pathophysiological in PD. Within REM sleep, stronger cortical delta activity specifically predicted reduced pathophysiological cortico-basal neural network features. Additionally, REM delta power significantly predicted greater self-reported morning alertness. These findings highlight a potentially protective role of REM sleep in cortico-basal network health in PD and daytime subjective experience, representing a potential target for closed loop neuromodulation therapies to impact neurodegenerative disease progression.

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Zhang, J.-X., Smyth, C., Anjum, M. F., Leng, Y., Krystal, A. D., Starr, P. A., Little, S.. 2025-05-13. A protective role of REM sleep in the pathological basal ganglia-cortical circuit of Parkinson's disease. https://doi.org/10.1101/2025.05.07.652676

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