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bioRxiv · 10.1101/2022.08.07.503118

Resting-state aperiodic neural activity as a novel objective marker of daytime somnolence

Cross, Z. R.·Kang, T. Y.·Lushington, K.·Sarkar, P.·Singh, P.·Johnston, S.·Yeo, A.·Chatburn, A.
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Abstract

Study ObjectivesCurrent assessment of excessive daytime somnolence (EDS) requires subjective measurements such as the Epworth Sleepiness Scale (ESS), and/or resource intensive sleep laboratory investigations. Recent work 1,2 has called for more non-performance-based measures of EDS. One promising non-performance-based measure of EDS is the aperiodic component of electroencephalography (EEG). Aperiodic (non-oscillatory) activity reflects excitation/inhibition ratios of neural populations and is altered in various states of consciousness, and thus may be a potential biomarker of hypersomnolence. MethodsWe retrospectively analysed EEG data from patients who underwent a Multiple Sleep Latency Test (MSLT) and determined whether aperiodic neural activity is predictive of EDS. Participants having undergone laboratory polysomnogram and next day MSLT were grouped into MSLT+ (n = 26) and MSLT- (n = 33) groups (mean sleep latency of < 8min and > 10min, respectively) and compared against a non-clinical (Control) group of participants (n = 26). ResultsWhile the MSLT+ and MSLT- groups did not differ in their aperiodic activity, the Control group had a significantly flatter slope and larger offset compared to both MSLT+ and MSLT- groups. Logistic regression machine learning predicted group status (i.e., symptomatic, non-symptomatic) with 90% accuracy based on the aperiodic slope while controlling for age. Slow oscillation-spindle coupling was also significantly stronger in the Control group relative to MSLT+ and MSLT- groups. ConclusionsOur results provide first evidence that aperiodic neural dynamics and sleep-based cross-frequency coupling is predictive of EDS, thereby providing a novel avenue for basic and applied research in the study of sleepiness.

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Cross, Z. R., Kang, T. Y., Lushington, K., Sarkar, P., Singh, P., Johnston, S., Yeo, A., Chatburn, A.. 2022-08-11. Resting-state aperiodic neural activity as a novel objective marker of daytime somnolence. https://doi.org/10.1101/2022.08.07.503118

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