Chang F, Li H Z, Zhang S Y, Chen C, Liu C, Fan H Y, Xing Y, Zahng Q T, Cai W X
School of Psychiatry, Wenzhou Medical University, Wenzhou 325035, Zhejiang Province, China.
Shanghai Key Laboratory of Forensic Medicine, Key Laboratory of Forensic Science, Ministry of Justice, Shanghai Forensic Service Platform, Academy of Forensic Science, Shanghai 200063, China.
Fa Yi Xue Za Zhi. 2020 Feb;36(1):52-60. doi: 10.12116/j.issn.1004-5619.2020.01.011.
Objective To discuss the activation characteristics of the prefrontal cortex of people with mild cognitive impairment （MCI） due to brain trauma during working memory tasks. Methods The psychological experiment design software E-prime was used and N-back paradigm was adopted as working memory task. Functional near-infrared spectroscopy （fNIRS） was used to detect changes in cortical oxygenated hemoglobin concentrations of 22 channels within the prefrontal lobe of 24 people with MCI due to brain trauma （study group） and 27 healthy volunteers （control group） with matching gender and age. Behavioral data, such as the number of keystroke errors and reaction time, were recorded simultaneously. Independent samples t test and non-parametric test were used to compare the mean value of oxygenated hemoglobin concentration change, the number of key errors and the mean value of reaction time of the two groups in each task. Results （1） The differences in the number of errors and reaction time between the two groups in 1-back and 2-back tasks had statistical significance （<0.05）.The main effects of task load and group were both significant （task =14.11, =0.001 1; group =10.39, =0.001 5）. （2） During the 1-back task, the differences in oxygenated hemoglobin concentration changes of the 22 channels between the two groups had no statistical significance （>0.05）. During the 2-back task, the differences in oxygenated hemoglobin concentration changes of the two groups in channel 2, 3, 7, 9, 10, 11, 14, 15, 18, 19, 21 and 22 had statistical significance （<0.05）. （3） In the 1-back task, the left frontal pole and dorsolateral prefrontal area in both groups were activated. In the 2-back task, the activation areas of the control group were the left frontal pole area and the left dorsolateral prefrontal area, while that of the study group almost covered most of the left and right frontal pole areas, which were scattered and the right area was activated, too. Conclusion Patients with MCI due to brain trauma have obvious working memory impairment, and during the 2-back working memory task, the activation of the prefrontal lobe decreased, but the activation range was wider.
目的 探讨脑外伤所致轻度认知障碍（MCI）患者在工作记忆任务期间前额叶皮质的激活特征。方法 使用心理实验设计软件E-prime，采用N-回溯范式作为工作记忆任务。运用功能近红外光谱技术（fNIRS）检测24例脑外伤所致MCI患者（研究组）和27名性别、年龄相匹配的健康志愿者（对照组）额叶前部22个通道的皮质氧合血红蛋白浓度变化。同时记录按键错误数和反应时间等行为学数据。采用独立样本t检验和非参数检验比较两组在各任务中氧合血红蛋白浓度变化均值、按键错误数和反应时间均值。结果 （1）两组在1-回溯和2-回溯任务中的错误数和反应时间差异具有统计学意义（<0.05）。任务负荷和组别的主效应均显著（任务=14.11，=0.001 1；组别=10.39，=0.001 5）。（2）在1-回溯任务期间,两组22个通道的氧合血红蛋白浓度变化差异无统计学意义（>0.05）。在2-回溯任务期间，两组在通道2、3、7、9、10、11、14、15、18、19、21和22的氧合血红蛋白浓度变化差异具有统计学意义（<0.05）。（3）在1-回溯任务中，两组的左侧额极和背外侧前额叶区域均被激活。在2-回溯任务中，对照组的激活区域为左侧额极区和左侧背外侧前额叶区，而研究组的激活区域几乎覆盖了左右额极区的大部分，呈散在分布且右侧区域也被激活。结论 脑外伤所致MCI患者存在明显的工作记忆障碍，在2-回溯工作记忆任务期间，前额叶激活降低，但激活范围更广泛。
