Brain functional connectivity initiates structured reorganization at a critical oxygen threshold during hypoxia.

ABSTRACT: The human brain dynamically adapts to hypoxia, a reduction in oxygen essential for metabolism. The brain's adaptive response to hypoxia, however, remains unclear. We investigated dynamic functional connectivity (FC) in healthy adults under acute hypoxia (FiO₂ = 7.7%, 11.8%) using BOLD fMRI, physiological monitoring (PetO₂, PetCO₂, SpO₂), and a Go/No-Go task. Principal component analysis identified a hypoxia-responsive FC component involving 400 cerebral parcels. This component emerged with a critical drop in PetO₂ (~53 mmHg), preceding changes in SpO₂, BOLD signals, and behavior. These FC changes were network-specific and centered on the default mode network (DMN), which selectively synchronized with other high-level cogniti

SUBMITTER: Kang D 

PROVIDER: S-EPMC12393409 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature