Abstract:

Objective  To study the change in the brain activation area during the Chinese characters working memory task by functional magnetic resonance imaging (fMRI) in patients with chronic insomnia. Methods  Forty chronic insomniacs and 50 good sleepers underwent fMRI while performing the Chinese characters working memory task by using block design, then compared the difference of accuracy and reaction time between the experimental and control group, as well as the degree of brain activation in the Chinese characters working coding, maintaining and extract processes. Results  Chronic insomnia showed a longer response time and inaccuracy in the task (P=0.043, P=0.047). There are difference between chronic insomnia group and control group in brain activation area:occipital lobe, right frontal lobe and right limbic lobe showed increased activation in the coding process, while left frontal lobe showed declined activation in maintaining process. In extract process, right occipital lobe showed increased activation while declined activation in left caudate nucleus and right thalamus. Conclusion  There are compensatory activations in the right cortex during coding and extract process while choric insomnia undergoing the Chinese characters working task. Left frontal lobe activation declines in maintaining process. Subcortical activation declines in extract process. It suggests that abnormal activation and damage occur in processes of the Chinese characters working task with choric insomnia.

Key words: Chronic insomnia; Chinese characters working memory; Functional magnetic resonance imaging; Brain activation area

摘要：

目的  探讨慢性失眠患者汉字任务下脑激活区改变。 方法  对40例慢性失眠患者和50例正常对照组进行汉字工作记忆功能磁共振扫描。 结果  慢性失眠组与正常组脑激活区存在差异：慢性失眠组编码期枕叶、右前额和右边缘叶激活增强；保持期左前额激活下降；提取期激活增强区为右枕叶，激活下降区为左尾状核和右侧丘脑。 结论  慢性失眠患者在文字记忆任务编码期及提取期均出现了右脑皮层的代偿激活，保持期出现了左前额激活下降，提取期出现了皮层下区域激活的下降，提示慢性失眠在文字记忆处理过程出现了相关脑区的损害和异常激活。

关键词: 慢性失眠; 汉字工作记忆; 功能磁共振; 脑激活区