Dynamic Reorganization of Functional Connectivity During Post-Break Task Reengagement

• Published in: IEEE transactions on neural systems and rehabilitation engineering Vol. 30; pp. 157 - 166
• Main Authors: Gao, Lingyun, Yu, Jin, Zhu, Li, Wang, Sujie, Yuan, Jingjia, Li, Gang, Cai, Jiaye, Qi, Xucheng, Sun, Yi, Sun, Yu
• Format: Journal Article
• Language: English
• Published: United States IEEE 2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Biomedical engineering; Brain; Brain Mapping - methods; Cognition; Cognitive ability; Dynamic characteristics; Dynamic functional connectivity (FC); EEG; Electroencephalography; Fatigue; Frequencies; Frequency dependence; Heart rate; Humans; Intervention; Magnetic Resonance Imaging; Mental Fatigue - psychology; mental fatigue recovery; mid-task break; Neural networks; Recovery (Medical); Rest; Spatiotemporal phenomena; spatiotemporal reorganization; Sun; Task analysis; Vigilance
• ISSN: 1534-4320; 1558-0210
• DOI: 10.1109/TNSRE.2022.3142855

Because of the undesired fatigue-related consequences, accumulating efforts have been made to find an effective intervention to alleviate the suboptimal cognitive function caused by mental fatigue. Nonetheless, limitations of intervention and evaluation methods may hinder the revealing of underlying neural mechanisms of fatigue recovery. Through the newly-developed dynamic functional connectivity (FC) analysis framework, this study aims to investigate the effects of two types of mid-task interventions (i.e., rest-break and moderate-intensity exercise-break) on the dynamic reorganization of FC during the execution of psychomotor vigilance test (PVT). Using a sliding window approach, temporal brain networks within each frequency band (i.e., <inline-formula> <tex-math notation="LaTeX">\delta </tex-math></inline-formula>, <inline-formula> <tex-math notation="LaTeX">\theta </tex-math></inline-formula>, <inline-formula> <tex-math notation="LaTeX">\alpha </tex-math></inline-formula>, & <inline-formula> <tex-math notation="LaTeX">\beta </tex-math></inline-formula>) were estimated before and immediately after the intervention, and towards the end of the task to investigate the immediate and delayed effects respectively during post-break task reengagement. Behaviourally, similar beneficial effects of exercise- and rest-break on performance were observed, manifested by the immediate improvements after both interventions and a long-lasting influence towards the end of tasks. Moreover, temporal brain networks assessment showed significant immediate decreases of fluctuability, which was followed by an increase of fluctuability towards the end of intervention tasks. Furthermore, the temporal nodal measure revealed the channels with significant differences across tasks were mainly resided in the fronto-parietal areas that exhibited interesting frequency-dependent distribution. The observations of immediate and delayed dynamic FC reorganizations extend previous fatigue-related intervention and static FC studies, and provide new insight into the dynamic characteristics of FC during post-break task reengagement.