Locus coeruleus microstructural integrity is associated with vigilance vulnerability to sleep deprivation

Area of Science:

• Neuroscience
• Sleep Science
• Cognitive Psychology

Background:

• Sleep deprivation significantly impairs cognitive functions like vigilance and daily performance globally.
• Individual differences in vulnerability to sleep deprivation are well-documented but poorly understood.
• The locus coeruleus (LC), vital for sleep-wake regulation, is a potential key to these individual differences.

Purpose of the Study:

• To investigate if the microstructural integrity of the locus coeruleus (LC) at baseline can predict vigilance impairment during sleep deprivation.
• To determine if fractional anisotropy (FA) in the LC serves as a biomarker for sleep deprivation vulnerability.

Main Methods:

• Diffusion tensor imaging (DTI) was used to assess LC microstructural integrity (FA) in 60 healthy participants before sleep deprivation.
• Participants underwent a controlled in-laboratory sleep deprivation study.
• Psychomotor vigilance test (PVT) performance was measured to assess vigilance during sleep deprivation.

Main Results:

• Individuals with higher baseline LC FA exhibited less impairment in PVT performance after sleep deprivation.
• LC FA explained 10.8% of the variance in sleep-deprived PVT lapses.
• The association between LC FA and PVT performance was anatomically specific.

Conclusions:

• Baseline LC microstructural integrity, quantified by FA, is a significant predictor of vigilance performance during sleep deprivation.
• LC FA may function as a reliable biomarker for individual differences in vulnerability to sleep loss.
• These findings offer insights into the neural mechanisms underlying individual resilience to sleep deprivation.