Effects of Chronic High-Altitude Hypoxia on Attention Networks and Cardiovascular Regulation in Indigenous...

This study examined the effects of chronic high-altitude hypoxic exposure on attention networks in indigenous primary school students, integrating cardiovascular indices to explore underlying physiological mechanisms.

Three real-world altitude groups were established: low (2,200 m), mid (3,200 m), and high (4,200 m). Cardiovascular function was assessed via systolic blood pressure, diastolic blood pressure, and heart rate. Attentional performance was evaluated using the Attention Network Test (ANT), which provides measures of alerting, orienting, and executive control efficiency.

Cardiovascular indices followed a nonlinear pattern across altitudes, with systolic blood pressure, diastolic blood pressure, and heart rate being significantly higher at mid-altitude compared to both low and high altitudes. In contrast, attention performance exhibited an opposite trend: alerting and executive control efficiency were relatively reduced at mid-altitude but were comparable between the low- and high-altitude groups. Orienting efficiency did not differ significantly across the three altitude groups.

The findings reveal a dissociation between physiological regulation and cognitive performance under chronic hypoxia. To explain these results, we propose a U-shaped model of cardiovascular adaptation, where mid-altitude represents an incomplete compensatory state, while prolonged exposure at higher altitudes leads to stabilized cardiovascular function and preserved attentional performance. This integrative framework underscores the crucial role of physiological adaptation in shaping cognitive outcomes in high-altitude environments.