不同强度电刺激诱发SⅠ及SⅡ区激活的fMRI研究  

A Functional MRI Study on Human Primary(SⅠ) and Secondary(SⅡ) Somatosensory Cortices Activation Induced by Electrical Stimulation of Different Intensity

作　　者：王渊[1] 张明[1] 章士正[2] 鱼博浪[1] 刘海[2] 林伟[2] 蒋红[2] 

机构地区：[1]西安交通大学第一医院影像中心,陕西西安710061 [2]浙江大学邵逸夫医院放射科博士后流动站

出　　处：《实用放射学杂志》2005年第10期1016-1019,共4页Journal of Practical Radiology

基　　金：中国博士后科学基金资助项目(编号:2004035718)

摘　　要：目的利用功能磁共振成像技术(fMR I)观察主要躯体感觉区(SⅠ区)和第二躯体感觉区(SⅡ区)在不同强度电刺激时的激活反应,探讨SⅠ区和SⅡ区对于痛觉调控的作用。方法对10名右利手健康志愿者分别施加1倍痛阈、2倍痛阈、3倍痛阈3个不同强度电刺激任务,并对刺激期间的脑功能活动进行全脑fMR I扫描,应用功能性神经图像分析(AFNI)软件包进行后处理以显示SⅠ区和SⅡ区的激活变化。结果在1倍痛阈强度电刺激时,SⅠ区未见明显激活,SⅡ区外侧部表现出较弱的双侧非对称性激活;2倍痛阈电刺激可诱发对侧SⅠ区和双侧SⅡ区内侧部激活,但BOLD信号未见明显增强;3倍痛阈电刺激可使对侧SⅠ区和双侧SⅡ区激活强度和范围明显增大。结论在不同强度电刺激作用下,SⅠ区和SⅡ区分别表现出不同的激活特性,这将有助于理解高级中枢在痛觉调控网络中的不同贡献。Objective To observe regional activation changes of human primary （ SⅠ ） and secondary （ S Ⅱ ） somatosensory cortices indueed by eleetrieal stimulation of different intensity in fMRI and to diseuss the effeet of these areas in pain modulation. Methods 10 healthy right - handed volunteers were performed respeetively with different electrieal stimulation of one time, two times and three times pain threshold intensity , the whole - brain fMRI scan was implemented at the same time , all data were postproeessed by means of analysis of funetional neuroimages（AFNI） to reveal activated ehanges of S Ⅰ and S Ⅱ Results The activation elieited by electrical stimulation of one time pain threshold intensity loeated in lateral subregion of S Ⅱ bilaterally; while two times pain threshold intensity mainly activated medial subregion of S II compared to that by one time＇ s, but the BOLD signal showed no significant increase, furthermore, eontralateral S I was also aetivated subsignificantly ; When applying three times pain threshold intensity , eontralateral S Ⅰ and bilateral S Ⅱ displayed marked stimulation with larger aetivated area . Conclusion S Ⅰ and S Ⅱ shows diserepant activated eharaeteristies respectively during different intensity stimulation, this will help us comprehend the eontribution made by advaneed eentral nervous system in pain modulation network.

关 键 词：功能磁共振成像 电刺激 痛觉 SⅠ区 SⅡ区 

分 类 号：R445.2[医药卫生—影像医学与核医学] R454.1[医药卫生—诊断学]