|其他题名||The influence of High Altitude on Working Memory|
|关键词||高海拔 认知损伤 空间工作记忆 言语工作记忆 事件相关电位|
|摘要||近年，涌入高海拔地区旅游或工作者越来越多，低氧环境对个体认知功能的影响研究也不断增加。本研究基于认知资源限制理论，采用事件相关电位(Event-related potential, ERP)技术，通过n-back任务和延迟样本匹配任务，探讨长期高海拔对工作记忆系统中视空间模板、语音环和中央执行功能（刷新和保持）三个子成分的影响机制。并通过追踪研究和对比不同高海拔地区工作记忆的差异，探讨高海拔对工作记忆影响的时间和空间效应。|
论文包括四项研究：1）比较20名西藏大学四年级学生和20 名从未到过高海拔地区的同龄大学生言语和空间n-back任务测试成绩， 考察其工作记忆的刷新能力；2）比较22名西藏大学四年级学生和23 名从未到过高海拔地区的同龄大学生的延迟样本匹配任务测试成绩，考察其工作记忆的保持能力；3）比较18名海拔2700米左右、23名3700米左右和23名4200米左右地区长大被试的言语和空间n-back任务测试成绩，系统考察不同海拔高度对工作记忆刷新能力的影响；4）分三次（7天、3月、1年）测试26名刚入藏的汉族大学生的n-back任务，第二次、第三次测试分别招募了24名和32名同龄对照组， 系统考察其言语和空间工作记忆随居住高海拔时间变化的变化特点。
|其他摘要|| In recent years, there have been an increasing population living at high altitude (HA) due to immigration, work duty or tourism. More studies began to concern whether high altitude hypoxic impact these individual`s cognitive. In the present study, based on Cognitive resource constraints theory, we used the event‐related potentials (ERP) and follow‐up study by The n‐back tasks and delayed matching‐to‐sample task (DSMT) to explore the underlying neutral mechanism of influences of high altitude hypoxia on three subsystems of working memory, phonological loop、 visuospatial sketh pad and the central executive, and to explore space and time effect of impact of high altitude hypoxia on working memory. |
The current paper contained four researchs, which in turn were 1) to select 20 college students who have lived at 3700m altitude for three years and 20 college students who were born and grown up at sea level place to measure working memory by n‐back task, so as to systematically investigate altitude effect of refreshing of verbal and spatial working memory; 2) to select 22 college students who have lived at 3700m altitude for three years and 23 college students who were born and grown up at sea level place to measure working memory by DMST task, so
as to systematically investigate altitude effect of capacity of working memory; 3) to select 23 college students who have born and grown up at 3700m altitude, 18 college students who have born and grown up at 2700m altitude, and 23 college students who have born and grown up at 4200m altitude to measure working memory by n‐back task, so as to systematically investigate altitude effect of refreshing of verbal and spatial working memory; 4) to select 26 college students who have reached at 3700m altitude for less than seven days to measure working memory by n‐back task for three time (7days, 3 months, and 1 years ), select 24 college students as a control
group at the second measure, and select another 32 college students as a control group at the third measure, so as to systematically investigate time effect exposure to high altitude of refreshing of verbal and spatial working memory.
We found that:
(1) we found P3 which was closed associated with the updating function at the parietal were influenced by high altitude hypoxia in both verbal and spatial tasks, and high altitude group have a memory load effect. This indicated that the load of instaneous refresh was increased in high altitude group compare to low altitude group. The LPC amplitude at the prefrontal have a memory load effect in the spatial tasks , but not in the verbal tasks. This indicated that the effort in spatial information representation in high altitude group was more than in low altitude group.
(2) In the working memory capacity, The CDA amplitudes have a significant difference at the time period of 300 470 ms between the low cognitive load without interference condition and the low cognitive load with interference in the high altitude group, but not in low altitude group. This result implied the working momory capacity on the high altitude group was reduced.
(3) The study by compare the results from three different high altitude found that high altitude have an impaired effect to verbal and spatial working memory when the altitude is more than 4000 m. Indigenous individuals compensate the impaired by enhancing cognitive effort. However, We also found an impaired effect at 3700m altitude, it is difficult to determine that 4000m altitude is a thershold lead to cognitive impaired.
(4) The follow‐up study found the correct rate of reaction in the verbal tasks have a significant decreased when acute exposured to altitude. This indicated that acute hypoxia may lead to decreased verbal working memory. However, Verbal working memory has shown no obvious altitude effect after three months of adjustment period.
Conclusion：The load of instaneous refresh was increased in high altitude group and the capacity of representation in working memory was reduced compare to low altitude group. The impaired effect was appearance at 3700 m altitude. The verbal working memory affected by acute hypoxia, but the spatial working memory was not.
|马海林. 高原低氧环境对工作记忆的影响[D]. 北京. 中国科学院研究生院,2015.|