Chaozong Ma,1,* Jiaxi Peng,2,* Yan Li,3 Anping Ouyang,1 Yangsen Huang,1 Wei He,4 Yuanqiang Zhu,5 Peng Fang1,6,7 

1Military Medical Psychology School, Fourth Military Medical University, Xi’an, People’s Republic of China; 2Mental Health Education Center, Chengdu University, Chengdu, People’s Republic of China; 3Department of Psychology, Tsinghua University, Beijing, People’s Republic of China; 4Department of Radiation Protection Medicine, Department of Military Preventive Medicine, Air Force Military Medical University, Xi’an, People’s Republic of China; 5Department of Radiology, Xijing Hospital, Fourth Military Medical University, Xi’an, People’s Republic of China; 6Shaanxi Provincial Key Laboratory of Bioelectromagnetic Detection and Intelligent Perception, Xi’an, People’s Republic of China; 7Military Medical Innovation Center, Fourth Military Medical University, Xi’an, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Peng Fang, Military Medical Psychology School, Fourth Military Medical University, Xi’an, People’s Republic of China, Email fangpeng@fmmu.edu.cn Yuanqiang Zhu, Department of Radiology, Xijing Hospital, Fourth Military Medical University, Xi’an, People’s Republic of China, Email Zhu_YQ_fmmu@163.com

Purpose: Sleep can repair the brain damage caused by sleep deprivation (SD), however in many cases, it may not be feasible to get sufficient sleep. Napping is a simple strategy to mitigate the detrimental impacts of SD. However, the underlying mechanism behind how napping contributes to brain repair remains unclear. Electroencephalogram (EEG) microstate analysis is sensitive in detecting bottom-up and top-down attention control and rapid transitions between quasi-stable brain states due to its temporal resolution. This study aims to explore the effects of napping on cognitive impairments cause by SD and the potential mechanisms of cognitive recovery.
Patients and Methods: We recruited forty-two healthy volunteers and recorded their EEG signals and psychomotor vigilance task (PVT) data at three time points: rested wakefulness, post-SD, and post-nap. EEG microstates analysis was used to explore changes of brain dynamic network. In addition, we investigate the alterations in microstate parameters and their correlation with behavior.
Results: We observed a significant decrease in participants’ alertness levels following SD, which subsequently improved after napping. Four microstate classes (A, B, C, D) were identified by using EEG microstate analysis. The B-D transition increased significantly after SD and returned to baseline after napping, while A-D transition revealed opposite patterns. Notably, changes of time coverage and occurrence in microstate D were significantly correlated with changes of PVT performance after both SD and nap conditions.
Conclusion: Our results provide empirical evidence that short naps can effectively reverse negative effects of SD on vigilant attention, primarily through restoring the functionality of key brain networks involved in attention regulation.

Keywords: sleep deprivation, short naps, EEG microstate, psychomotor vigilance task, cognitive recovery