The performance and quantitative EEG oncontinuous cognitive tasks in patients withchronic fatigue syndrome

• Main Authors: Ming-Hui Hsieh, 謝明慧
• Other Authors: Lung Yu
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/19557038681669700375

碩士 === 國立成功大學 === 行為醫學研究所 === 90 === Abstract Objective: The purpose of this study was to explore the pattern of inner resources utilization while doing continuous cognitive tasks in chronic fatigue syndrome (CFS) patients, in order to understand the cognitive impairments and the phenomenon of fatigue in these patients. Methods: Twelve CFS subjects and twelve healthy control subjects participated in this study. Their reaction time and EEG were recorded when they were performing an easy and a difficult version of working memory tasks, and a vigilance task. Also, 6 minutes of resting EEG were collected for all subjects and they were asked to complete a mood visual analogue scale before and after doing all the tasks. Results: When performing the easy version of working memory task, CFS subjects had longer reaction time but same omission and commission rate. When the task were divided into 4 segments over time, the average reaction time in healthy control subjects showed a learning effect as well as a boredom or fatigue effect, which were not present in CFS group. For the EEG measures, CFS subjects had higher arousal level even while performing the easy version of working memory task, but showed EEG pattern of fatigue level sooner. In difficult version of working memory, CFS subjects had lower commission rate than control subjects had, but there were no differences in EEG pattern. After performing all the tasks, CFS subjects rated their subjective anxiety level higher than in the beginning of all the tasks. In contrast, control subjects showed a decline in their level of anxiety. Conclusion: Behaviorally, CFS patients tend to maintain a constant level of performance, disregarding the increase in familiarity with the task. However, EEG data indicated earlier sign of fatigue and increased level of arousal in CFS patients. The results suggested a defect in the utilization of inner resources in CFS patients. They strive to maintain a constant level of performance and lack of the flexibility to modulate their mental efforts according to outside situation. This might contribute to their reported fatigue and impaired cognitive function.