认知与发展心理学研究室知识库

西藏自治区常住人口 300.22 万人，随着援藏政策和西部大开发战略实施，越来越多人来到西藏工作或旅游。高海拔低氧环境对个体认知功能影响的研究也逐渐增多。本研究基于冲突监测理论（conflict monitoring theory）和额叶相关抑制衰退模型，采用事件相关电位（Event-related potential，ERP）技术，通过注意网络测试（attention network test，ANT）任务和 Stroop2-1反应映射任务，考察长期高海拔低氧环境对抑制控制功能的影响及其神经机制； 并通过追踪研究和对比高低海拔地区抑制控制功能的差异来探讨高海拔低氧环境对抑制控制功能影响的时间效应和空间效应。  
论文包括三个实验：1）采用“ANT注意网络测试”对生长在低海拔地区首次进入高海拔（3650m）地区的青年人（23人）进行为期两年的行为追踪测试，考察高海拔低氧环境对注意警觉功能、定向功能和执行控制功能影响的时间效应；2）采用 ERP 技术对生长在低海拔地区首次进入高海拔（3650m）地区居住满两年的青年人（24 人）再次进行“ANT 注意网络测试”，并与低海拔组（25人）进行比较，在第一项研究的基础上，考察高海拔低氧环境对执行控制功能影响的神经机制；3）采用刺激冲突和反应冲突分离的“Stroop2-1反应映射任务”再次测试实验二的两组被试，考察高海拔低氧环境对抑制控制功能中刺激冲突和反应冲突的影响。
研究结果如下：
（1）实验一：从平原地区进入高海拔地区驻留一个月后执行控制功能比一周时显著上升，驻留两年后的执行控制功能比一个月时显著下降，但仍显著高于驻留一周时。警觉和定向功能的时间效应不显著。
（2）实验二：在生理指标上，与低海拔组相比，高海拔组的脉率更高，血氧饱和度更低；行为数据上，总反应时更长；同时，ERP 结果显示，在执行控制功能上，高海拔组 N2 成分平均波幅大于低海拔组；不一致条件下的 P3 成分平均波幅小于低海拔组。
（3）实验三：与刺激不一致&反应一致条件相比，高、低海拔组在一致条件下反应时更短、正确率更高；与刺激&反应都不一致条件相比，刺激不一致&反应一致条件下反应时更短、正确率更高。此外，依据减数法逻辑计算反应时后发现，两组反应冲突效应大于刺激冲突效应。ERP 结果发现，高海拔组 P2 成分平均波幅大于低海拔组；高海拔组MFN成分平均波幅在300-400 ms 和 400-550 ms 间都显著大于低海拔组；同时，高海拔组在左前额区域的 SP 波比低海拔组更负，在右前额区域的 SP 波比低海拔组更正，在顶叶区域与低海拔组没有显著差异。
本研究结论如下：执行控制功能随在高海拔驻留时间延长而变化，其规律与对高海拔的生理适应阶段相吻合，具体表现为进入高海拔一周时显著下降，一月后有所恢复，两年后再次下降；其中，在高海拔驻留两年时，大脑执行控制功能下降的原因是冲突监测能力和冲突解决阶段的冲突控制能力下降；此外，高海拔低氧环境对大脑早期刺激冲突和晚期反应冲突的监测以及反应冲突的解决都有影响，高海拔组以投入更多的注意资源来完成对冲突的监测和解决。

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.