An autonomic mode of brain activity

Area of Science:

• Neuroscience
• Autonomic Nervous System
• Sleep Research

Background:

• The interplay between autonomic and central nervous systems is crucial for brain function, yet its role during physiological challenges like sleep deprivation (SD) remains poorly understood.
• Understanding these interactions is vital for maintaining brain health and function under stress.

Purpose of the Study:

• To investigate the impact of sleep deprivation on autonomic-central nervous system interactions and brain activity.
• To explore the relationship between autonomic-related brain networks, physiological signals, and brain amyloid beta burden during sleep deprivation.

Main Methods:

• Utilized functional magnetic resonance imaging (fMRI) to measure brain activity and cardiorespiratory signals.
• Employed positron emission tomography (PET) to assess baseline brain amyloid beta burden.
• Analyzed low-frequency (< 0.1 Hz) synchronized activity and phase coherence between autonomic and central nervous system networks.

Main Results:

• Sleep deprivation significantly increased synchronized low-frequency activity in autonomic networks (AN), including attention, visual, and sensorimotor regions.
• SD induced significant phase coherence between pulse signals and medial brain networks, and respiratory variations and cerebellar networks.
• Higher AN low-frequency power during SD correlated with pulse-medial and respiratory-cerebellar network coherences (R² = 0.78).
• Increased AN low-frequency power during SD was associated with lower brain amyloid beta burden.

Conclusions:

• Sleep deprivation induces a distinct autonomic mode of synchronized brain activity characterized by specific autonomic-central nervous system interactions.
• Global cortical synchronization during sleep deprivation is directly relevant to brain clearance mechanisms, as indicated by the association with amyloid beta burden.