Chen Xiaoming, Zhang Qian, Wang Jiye, Liu Jie, Zhang Wenbin, Qi Shun, Xu Hui, Li Chen, Zhang Jinsong, Zhao Haitao, Meng Shanshan, Li Dan, Lu Huanyu, Aschner Michael, Li Bin, Yin Hong, Chen Jingyuan, Luo Wenjing
Department of Occupational and Environmental Health, the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an, China.
Department of Radiology, General Hospital of Tibet Military Region, Lhasa, China.
Hum Brain Mapp. 2017 Aug;38(8):3865-3877. doi: 10.1002/hbm.23635. Epub 2017 May 8.
Cognitive and neuroimaging changes under chronic high-altitude exposure have never been followed up and dynamically assessed.
To investigate the cognitive and brain structural/functional alterations associated with chronic high-altitude exposure.
Sixty-nine college freshmen that were immigrating to Tibet were enrolled and followed up for two years. Neuropsychological tests, including verbal/visual memory and simple/recognition reaction time, were utilized to determine whether the subjects' cognitive function had changed in response to chronic high-altitude exposure. Structural magnetic resonance imaging (MRI) and resting-state functional MRI (rs-fMRI) were used to quantify brain gray matter (GM) volumes, regional homogeneity (ReHo) and functional connectivity (FC) alterations before and after exposure. Areas with changes in both GM and ReHo were used as seeds in the inter-regional FC analysis.
The subjects showed significantly lower accuracy in memory tests and longer reaction times after exposure, and neuroimaging analysis showed markedly decreased GM volumes and ReHo in the left putamen. FC analysis seeding of the left putamen showed significantly weakened FC with the superior temporal gyrus, anterior/middle cingulate gyrus and other brain regions. In addition, decreased ReHo was found in the superior temporal gyrus, superior parietal lobule, anterior cingulate gyrus and medial frontal gyrus, while increased ReHo was found in the hippocampus. Differences in ReHo/FC before and after high-altitude exposure in multiple regions were significantly correlated with the cognitive changes.
Cognitive functions such as working memory and psychomotor function are impaired during chronic high-altitude exposure. The putamen may play an important role in chronic hypoxia-induced cognitive impairment. Hum Brain Mapp 38:3865-3877, 2017. © 2017 Wiley Periodicals, Inc.
慢性高原暴露下的认知和神经影像学变化从未得到随访及动态评估。
研究与慢性高原暴露相关的认知及脑结构/功能改变。
招募69名移居至西藏的大学新生，并对其进行为期两年的随访。采用包括言语/视觉记忆以及简单/识别反应时间的神经心理学测试，以确定受试者的认知功能是否因慢性高原暴露而发生变化。利用结构磁共振成像（MRI）和静息态功能MRI（rs-fMRI）对暴露前后脑灰质（GM）体积、局部一致性（ReHo）和功能连接（FC）改变进行量化。将GM和ReHo均发生变化的区域用作区域间FC分析的种子点。
暴露后，受试者在记忆测试中的准确率显著降低，反应时间延长，神经影像学分析显示左侧壳核的GM体积和ReHo明显减少。以左侧壳核为种子点的FC分析显示，与颞上回、前/中扣带回及其他脑区的FC显著减弱。此外，颞上回、顶上小叶、前扣带回和额内侧回的ReHo降低，而海马体的ReHo增加。多个区域高原暴露前后ReHo/FC的差异与认知变化显著相关。
慢性高原暴露期间，工作记忆和精神运动功能等认知功能受损。壳核可能在慢性缺氧诱导的认知障碍中起重要作用。《人类大脑图谱》38:3865 - 3877, 2017年。© 2017威利期刊公司。
