There are 3.22 million inhabitants in Tibet Autonomous Region, with the Tibet policy and the western development strategy, more and more people come to Tibet for work or travel. The studies of how high altitude hypoxia environment effects cognitive function is also gradually increased. Based on Conflict Monitoring Theory and Associated with frontal lobe suppression model of the recession, we used the event-related potentials (ERP) and follow-up study by Attention network test (ANT) and 2–1 mapping Stroop task to explore the neutral mechanism of influences of high altitude hypoxia on inhibition control function; by tracking research and comparative high and low altitude differences in inhibitory control function to explore spatial and temporal impact of high altitude hypoxia on inhibition control function.
This paper contained three experiments, 1) 23 college students, who were born and grown up at sea level place and entering the high altitude area (3650m) for the first time were recruit. Data collected in one week, one month and two years at high altitude area, respectively by ANT to explore temporal impact of high altitude hypoxia on alerting function, orienting function and executive control function; 2) 24 college students who have lived at 3650m altitude for two years and 25 college students who were born and grown up at sea level place were recruit to measure ANT by ERP to explore the underlying neutral mechanism of influences of high altitude hypoxia on executive control function; 3) The above subjects were tested again by 2–1 mapping Stroop task to explore the neutral mechanism the influences of high altitude hypoxia on stimuli conflict and response conflict.
Following are the results:
(1) Experiment 1: Executive control function of attention network is significantly affected by residence time: Post-hoc analysis demonstrated that executive control function performance significantly increased after one month but significantly decreased two years, late although remain significantly higher than that of baseline test. Alerting function and orienting function are not significantly affected by residence time.
(2) Experiment 2: Compared with that the low altitude group, the pulse rate of the high altitude group was higher and the oxygen saturation was lower in the physiological index. The towage response time of the high altitude group was longer. At the same time, the EEG analysis showed that the amplitude of N2 and incongruent P3 component of the high altitude group was smaller than that of the low altitude group.
(3) Experiment 3: Comparison of the behavior data, the reaction time of both high altitude group and the low altitude group were shorter in the SI condition than in the CO condition, and the correct rates were higher too; the reaction time in RI condition were shorter than that in the SI condition, the same to correct rates. Based on the subtraction logic, the response effect is longer than the stimulus effect both in low altitude group and high altitude group. The EEG analysis showed that the P2 component of the high altitude group was significantly higher than that of the low altitude group; the MFN component of the high altitude group was significantly higher than that of the low altitude group at 300-400 ms and 400-550 ms; In addition, the SP amplitude of the high altitude group in the left frontal–temporal region was lower than that in the low altitude group, and the SP amplitude in the right frontal–temporal region was higher than that in the low altitude group; There was no significant in the parietal region.
Conclusion：Executive control function is significantly affected by residence time in high altitude. The executive control function first decreased in the first week in arrival, then restored within a month and declined again after two year in along with the extension of residence time; two years exposure to high altitude affects conflict monitoring and conflict control in the conflict-resolving stage; in addition, it also affects conflict monitoring in the stimuli and response conflict stage as well as conflict-resolving stage, and that attention resources are decreased to resist the conflict monitoring and control in the high-altitude group.