Sleep-EEG-based parameters for discriminating fatigue and sleepiness.

Area of Science:

• Neuroscience
• Sleep Medicine
• Biomarkers

Background:

• Evaluating sleep quality is complex, often conflating recovery from fatigue and sleepiness.
• Distinguishing between fatigue and sleepiness is crucial for accurate sleep quality assessment.

Purpose of the Study:

• To identify electroencephalogram (EEG) biomarkers differentiating daytime fatigue and sleepiness.
• To assess sleep quality by considering distinct recovery patterns from fatigue and sleepiness.

Main Methods:

• Collected questionnaire data on fatigue and sleepiness from 754 Japanese employees.
• Recorded one-channel EEG data during sleep.
• Categorized participants into four groups based on fatigue and sleepiness levels (FS, FO, SO, NE).
• Compared sleep parameters (powers, durations) across groups using statistical tests.

Main Results:

• Significant differences in specific sleep parameters were observed among the four groups.
• Theta Delta power emerged as a potential biomarker to discriminate between fatigue and sleepiness.
• Delta and Theta powers correlated with sleep quality related to sleepiness and fatigue recovery, respectively.
• Mid-arousal frequency and duration may aid fatigue recovery.

Conclusions:

• Fatigue and sleepiness exert differential effects on sleep architecture and quality.
• Multiple EEG-derived sleep parameters are associated with subjective sleep quality.
• Theta Delta power shows potential for distinguishing fatigue from sleepiness, aiding sleep quality assessment.