人脑对食物视觉刺激反应的功能磁共振成像的任务模式研究  

A STUDY ON THE VISUAL STIMULATIONS TASK MODALITIES FOR THE FUNCTIONAL MAGNETIC RESONANCE IMAGING TO THE HUMAN BRAIN RESPONSE TO FOOD

作　　者：倪皖东[1] 张德玄[2] 韩济生[3] 罗述谦[1] 

机构地区：[1]首都医科大学生物医学工程学院,北京100054 [2]杭州师范学院医学院,杭州310012 [3]北京大学神经科学研究所,北京100871

出　　处：《中国生物医学工程学报》2004年第2期127-133,共7页Chinese Journal of Biomedical Engineering

摘　　要：虽然正电子发射断层成像 (positronemissiontomography ,PET)实验研究证明 ,杏仁核、眶额皮质与人脑在饥饿状态下对食物视觉刺激反应相关 ,但它对人体有微创、时间分辨率低、成本高的缺陷限制了人们在这方面的进一步研究。功能磁共振成像克服了这些缺陷 ,并且它的数据可以单例处理。但它的实验设计比PET的复杂 ,目前也没有较多任务模式设计经验可以借鉴。因此 ,要进行这方面的预实验。 5名健康志愿受试者随机分 3组 ,选择组块、事件相关和快速事件相关任务模式中的一种 ,禁食 12h后扫描。成像过程中 ,受试者接受随机播放的食物图片、非食物图片和空白模糊图片的视觉刺激。再采用SPM2软件处理功能像数据。对感兴趣的食品图片与中性物品图片的对比、食品图片与空白对照组图片对比的相关功能区域进行了t检验后发现 ,事件相关任务模式所得到的相关功能区 ,比其他两类任务模式的相应区域较多地包含了杏仁核、眶额皮质区 ,与既往PET的实验结果相符程度最大。可见事件相关任务模式是一种相对稳定的功能成像模式。Many results of positron emission tomography experiments have proved that the responses in amygdala and orbitofrontal cortex are most related to the food stimulation in human brain during fasting; however, its slight injury to human body, low time resolution and high cost bring us a limitation to the further research. Comparing with PET, fMRI has the advantages of high time resolution, low cost and moreover, the data acquired by fMRI can be processed and analysed in single case. Because of the visual stimuli task modality design for fMRI method is usually much more complicated than the one for PET method and there are not yet enough mature experiences can be used for reference, a preliminary study was carried out in this work. 5 healthy volunteers were divided into 3 groups which was respectively accepted the modalities of block design, event-related design and fast event-related design. After fasting for 12 hours, the subjects accepted the visual stimuli by the randomly presented pictures of food, non-food and blurs objects while being fMRI scanned. The functional data was processed with software SPM2. Using a t-test to the contrasted ROIs (regions of interesting, ROI) among the regions activated respectively by food picture blur picture and non-food picture, it was found that the ROIs acquired by the event related modality visual task were much more matched to the ROIs acquired by PET than the ROIs acquired by the other two kinds of modalities. Therefore, it is suggested that the event related modality is the fittest one for fMRI research.

关 键 词：功能磁共振成像 杏仁核 眶额皮质 事件相关诗计 

分 类 号：R318.04[医药卫生—生物医学工程]