EEG and gut microbiota response patterns in high-altitude indigenous populations.

Residents at 4 km altitude showed enhanced delta (1-4 Hz) power across most brain regions during resting state.

• Resting-state EEG was recorded in 135 of the 211 total participants
• Participants were distributed across 2, 3, and 4 km altitude groups
• Delta power enhancement was observed across most brain regions in the 4 km group compared to lower altitude groups
• Delta frequency band was defined as 1-4 Hz

Residents at 4 km altitude showed increased frontal-occipital functional connectivity (FC) during resting state.

• Functional connectivity was assessed using resting-state EEG recordings
• The increase in FC was specifically observed in the frontal-occipital direction
• This finding was identified in the 4 km altitude indigenous population group
• Functional connectivity patterns were compared across populations at 2, 3, and 4 km altitudes

The 4 km altitude group exhibited elevated P3 amplitude in response to oddball stimuli during a cognitive oddball task.

• A task-based EEG paradigm using a cognitive oddball task was employed
• Elevated P3 amplitude was observed specifically in response to oddball stimuli in the 4 km group
• The 4 km group also showed larger parietal delta power during the cognitive task
• Task-based EEG was recorded in 135 participants across the three altitude groups

The 4 km altitude group displayed higher species richness and elevated abundance of short-chain fatty acid-producing gut microbiota genera.

• Gut microbiota profiling was conducted using 16S rRNA in 211 high-altitude indigenous populations
• Participants were sampled at 2, 3, and 4 km altitudes
• Genera with elevated abundance at 4 km included Roseburia, Blautia, and Coprococcus
• These genera are characterized as short-chain fatty acid-producing
• The 4 km group showed higher species richness compared to lower altitude groups

Abundance of Blautia was positively associated with resting-state functional connectivity, which may further influence anxiety and sleep quality.

• A positive association was identified between Blautia abundance and resting-state FC
• This relationship was observed in indigenous high-altitude populations
• The association between Blautia and FC was further linked to anxiety and sleep quality outcomes
• The authors describe this as reflecting a gut-brain interaction adaptation to high altitude

The study combined gut microbiota profiling and EEG recordings to characterize neurophysiological and microbial adaptations to chronic high-altitude hypoxia.

• Total sample size was 211 high-altitude indigenous individuals for gut microbiota profiling
• EEG recordings (both resting-state and task-based) were conducted in a subset of 135 participants
• Three altitude levels were compared: 2, 3, and 4 km
• 16S rRNA sequencing was used for gut microbiota profiling
• Both resting-state and cognitive task-based EEG paradigms were employed