Identifying individuals with high susceptibility to mental fatigue: A functional connectivity study

Area of Science:

• Neuroscience
• Cognitive Psychology
• Human Factors Engineering

Background:

• Prolonged cognitive tasks reveal significant individual differences in performance, suggesting underlying neural mechanisms of mental fatigue.
• Understanding these differences is crucial for identifying susceptibility and its impact on brain function.

Purpose of the Study:

• To identify individuals highly susceptible to mental fatigue.
• To investigate the influence of fatigue susceptibility on brain network reorganization.
• To develop a practical method for identifying fatigue-prone individuals.

Main Methods:

• Collected behavioral data and electroencephalography (EEG) signals from 95 participants during a 20-minute psychomotor vigilance task (PVT).
• Introduced a composite fatigue index (F_index) to categorize participants into fatigue-susceptible (FS) and fatigue-resistant (FR) groups.
• Analyzed functional connectivity and brain network properties, employing classification analyses for FS identification.

Main Results:

• The fatigue-susceptible group showed significant performance decline, while the fatigue-resistant group maintained stable performance.
• Brain network analyses revealed frequency-dependent reorganizations, with the FR group exhibiting greater stability and integrity than the FS group.
• Classification analyses achieved high accuracy (95.61%) for identifying FS individuals, highlighting centro-parietal brain regions.

Conclusions:

• Substantial individual differences exist in mental fatigue susceptibility.
• A practical approach using EEG and a composite index can effectively identify individuals prone to performance decline due to mental fatigue.
• Fatigue susceptibility is associated with specific patterns of brain network reorganization.