Development of aptitude at altitude.

Area of Science:

• Physiology
• Neuroscience
• Human Adaptation

Background:

• Millions live at high altitudes (>2500m) with limited oxygen.
• Brain and behavioral development in hypoxia is poorly understood.
• Studies on high-altitude populations are crucial for understanding human adaptation.

Purpose of the Study:

• To assess the physiological, cognitive, and behavioral profile of infants, children, and adolescents at varying Bolivian altitudes.
• To investigate the impact of chronic hypoxia on neurodevelopment and psychomotor function.
• To explore potential adaptive mechanisms to high-altitude living.

Main Methods:

• Studied infants (6-12m), children (6-10y), and adolescents (13-16y) at 500m, 2500m, and 3700m in Bolivia.
• Measured hemoglobin oxygen saturation and end-tidal carbon dioxide.
• Conducted neurodevelopmental, behavioral, and neuropsychological assessments, including cerebral blood flow velocity.

Main Results:

• Individuals above 2500m had lower oxygen saturation and carbon dioxide levels without health detriments.
• Infant neurodevelopment and behavior were comparable across altitudes.
• Children and adolescents showed reduced psychomotor speed with increasing altitude, linked to decreased cerebral blood flow velocity.

Conclusions:

• Psychomotor slowing at high altitudes may be an adaptive trait, not a deficit.
• Adaptation to hypoxia appears independent of ethnic genetic admixture.
• Reduced cerebral metabolism and blood flow may underlie psychomotor changes in hypoxic conditions.