Reversible brain functional alterations induced by Short-Term high altitude exposure

Area of Science:

• Neuroscience
• Altitude Medicine
• Physiology

Background:

• High altitude hypoxia causes physiological and neural changes.
• The dynamics of brain function changes after short-term exposure are not fully understood.

Purpose of the Study:

• Investigate physiological and neural effects of short-term high altitude exposure.
• Assess recovery of brain function after returning to low altitude.

Main Methods:

• Hematological parameters and brain functional activity were measured at three time points: pre-ascent, day 30 at high altitude, and two months post-ascent.
• Assessed regional homogeneity (ReHo), voxel-mirrored homotopic connectivity (VMHC), and functional connectivity (FC).

Main Results:

• High altitude exposure increased red blood cell count and hemoglobin, decreased SpO2, and altered ReHo, VMHC, and FC across multiple brain networks (visual, sensorimotor, subcortical, frontoparietal, ventral attention, default mode).
• Significant differences in ReHo were observed in the cerebellum, brainstem, fusiform, lingual, and precentral gyri.
• VMHC showed significant differences in occipital and postcentral cortices.

Conclusions:

• Physiological and brain functional measures demonstrated a similar recovery pattern.
• Brain function and physiological indices returned to baseline levels two months after returning to low altitude.
• Provides evidence for the reversibility of brain functional alterations after short-term high altitude exposure.