Painful stimuli evoke different stimulus-response functions in the amygdala, prefrontal, insula and somatosensory cortex:: a single-trial fMRI study
Painful stimuli evoke different stimulus-response functions in the amygdala, prefrontal, insula and somatosensory cortex:: a single-trial fMRI study
复制标题
DOI：
10.1093/brain/awf137
复制
发表时间：
2002-06-01
期刊：
影响因子：
14.5
通讯作者：
Büchel, C
中科院分区：
文献类型：
--
作者：
Bornhövd, K;Quante, M;Büchel, C
直到最近，神经影像学研究才从描述伤害性刺激激活的区域转移到解开伤害性系统中的亚过程。一种表征各个区域作用的方法是记录不同刺激强度引起的大脑反应。我们使用这样一个参数的单次试验功能性MRI设计结合钍：钇铝石榴石红外激光和研究疼痛，刺激强度和刺激意识（即疼痛无关）的反应在9名健康志愿者。四个刺激强度，从温暖到疼痛（300-600 mJ），以随机顺序施加，并由受试者在五点量表（P0-4）上进行评级。在背外侧前额叶皮层和顶内沟的地区之间的PO（未感知）和P1的分化，但没有表现出进一步的信号增加与P2，并与刺激感知和随后的认知处理。初级躯体感觉皮层的信号变化区分了非疼痛试验（P0和P1），将该区域与基本感觉处理联系起来。次级躯体感觉皮层和岛叶皮层中的疼痛相关区域显示出不区分无害试验（PO和P1）的反应，但与疼痛试验（P2-4）的信号变化呈正线性关系。这也是真实的杏仁核，除了，在PO试验中，刺激没有被感知（即“不确定”的试验），诱发信号的变化是一样大的P3试验，表明杏仁核参与编码的“不确定性”，已经提出了以前的经典条件反射。
Only recently have neuroimaging studies moved away from describing regions activated by noxious stimuli and started to disentangle subprocesses within the nociceptive system. One approach to characterizing the role of individual regions is to record brain responses evoked by different stimulus intensities. We used such a parametric single-trial functional MRI design in combination with a thulium:yttrium-aluminium-granate infrared laser and investigated pain, stimulus intensity and stimulus awareness (i.e. pain-unrelated) responses in nine healthy volunteers. Four stimulus intensities, ranging from warm to painful (300-600 mJ), were applied in a randomized order and rated by the subjects on a five-point scale (P0-4). Regions in the dorsolateral prefrontal cortex and the intraparietal sulcus differentiated between PO (not perceived) and P1 but exhibited no further signal increase with P2, and were related to stimulus perception and subsequent cognitive processing. Signal changes in the primary somatosensory cortex discriminated between non-painful trials (P0 and P1), linking this region to basic sensory processing. Pain-related regions in the secondary somatosensory cortex and insular cortex showed a response that did not distinguish between innocuous trials (PO and P1) but showed a positive linear relationship with signal changes for painful trials (P2-4). This was also true for the amygdala, with the exception that, in PO trials in which the stimulus was not perceived (i.e. 'uncertain' trials), the evoked signal changes were as great as in P3 trials, indicating that the amygdala is involved in coding 'uncertainty', as has been suggested previously in relation to classical conditioning.