Dynamic brain functional states associated with inhibition control under different altitudes.

Area of Science:

• Neuroscience
• Cognitive Science
• Altitude Physiology

Background:

• Chronic exposure to hypobaric hypoxia at high altitudes can affect cognitive functions.
• The impact of altitude on dynamic functional connectivity (dFC) of brain networks remains largely unknown.
• Understanding these changes is crucial for addressing cognitive impairments in plateau environments.

Purpose of the Study:

• To investigate how functional connectivity (FC) of brain networks changes with varying altitudes.
• To explore the dynamic functional connectivity states during cognitive tasks under high-altitude conditions.
• To identify potential neural mechanisms underlying cognitive adaptation or impairment due to plateau exposure.

Main Methods:

• Utilized electroencephalography (EEG) data from the Go/NoGo task in participants from Weinan (347m) and Nyingchi (2950m).
• Employed dynamic functional connectivity (dFC) analysis combined with K-means clustering to identify distinct FC states.
• Calculated temporal network properties including fractional windows (FW), transition numbers (TN), and mean dwell time (MDT).

Main Results:

• Two distinct dFC states were identified, with State 1 characterized by higher functional integration and segregation.
• Dynamic switching between dFC states occurred during the Go/NoGo task, with increased FW in State 1 for high-altitude participants.
• Regional analysis showed greater state deviation in fronto-parietal cortices and enhanced occipital lobe FC strength in high-altitude individuals.

Conclusions:

• Long-term high-altitude exposure reorganizes brain networks towards greater inter- and intra-network information transfer efficiency.
• These network changes may represent a compensatory mechanism for compromised brain function in hypobaric hypoxia.
• The study offers novel insights into how plateau environments impact cognitive function via brain network dynamics.