经皮电针刺激正常人耳甲迷走神经的功能MRI脑效应研究

Brain response to transcutaneous electronical stimulation on auricular concha of the healthy subjects using fMRI

目的探讨耳甲迷走神经刺激术的脑通路,为耳迷走神经刺激调制孤束核-边缘叶脑网络假说提供证据。材料与方法随机录用16名健康志愿者,参加经皮电刺激右耳甲部迷走神经分布区(t VNS),以同侧上耳舟部刺激为对照,记录刺激的耳部感觉,观察全脑6 min扫描的Bold-f MRI信号变化,分析脑功能激活特点,应用SPM8处理f MRI数据。结果两组电流、感觉频率及强度未见明显区别。经皮电刺激耳甲部t VNS正常人激发了左侧孤束核及边缘叶脑区广泛而较强的负激活效应,局限性激活位于体感区及岛叶等,而对照部产生了右侧三叉神经核等脑干核团负激活及脑部体感区明显的激活现象。结论经皮电刺激迷走神经产生了孤束核-边缘叶脑网络的调制效应,为经皮电刺激耳甲部迷走神经治疗抑郁症等脑中枢机制打下基础。

Objectives： To investigate the BOLD fMRI response to transcutaneous vagus nerve electronical stimulation（t VNS） at auricular concha region（ACR） on the healthy. It is hypothesized that tVNS modulates the network of nucleus of tract solitary-limbic system. Materials and Methods： Sixteen healthy subjects（18—27 y） were enrolled in the fMRI study. The fMRI was conducted during tVNS on ACR controlled with sham-tVNS on the superior scapha respectively. Subjects＇ sensations were recorded after every fMRI scan. Each functional scan lasted 6 minutes. SPM8 was employed for the fMRI data processing. Results： The current, and the sensations＇ frequency and strength of electronical stimulation were similar between two groups. The tVNS induced the predominant deactivation in the left nucleus of tract solitary and brain regions involving in limbic function, and the activation was limited in left SII, left anterior insula, etc. However, the sham tVNS showed the deactivation in the areas of right nucleus of trigeminal nerve, the obvious activation in the somato-sensory areas. Conclusions： tVNS modulated the network of nucleus of tract solitary-limbic system. It would provide the basis of therapeutic mechanism of tVNS treating Depression.