Gelnar P A, Krauss B R, Sheehe P R, Szeverenyi N M, Apkarian A V
Department of Neurosurgery, State University of New York Health Science Center, Syracuse, New York 13210, USA.
Neuroimage. 1999 Oct;10(4):460-82. doi: 10.1006/nimg.1999.0482.
Cortical activity due to a thermal painful stimulus applied to the right hand was studied in the middle third of the contralateral brain and compared to activations for vibrotactile and motor tasks using the same body part, in nine normal subjects. Cortical activity was demonstrated utilizing multislice echo-planar functional magnetic resonance imaging (fMRI) and a surface coil. The cortical activity was analyzed based upon individual subject activity maps and on group-averaged activity maps. The results show significant differences in activations across the three tasks and the cortical areas studied. The study indicates that fMRI enables examination of cortical networks subserving pain perception at an anatomical detail not available with other brain imaging techniques and shows that this cortical network underlying pain perception shares components with the networks underlying touch perception and motor execution. However, the thermal pain perception network also has components that are unique to this perception. The uniquely activated areas were in the secondary somatosensory region, insula, and posterior cingulate cortex. The posterior cingulate cortex activity was in a region that, in the monkey, receives nociceptive inputs from posterior thalamic medial and lateral nuclei that in turn are targets for spinothalamic terminations. Discrete subdivisions of the primary somatosensory and motor cortical areas were also activated in the thermal pain task, showing region-dependent differences in the extent of overlap with the other two tasks. Within the primary motor cortex, a hand region was preferentially active in the task in which the stimulus was painful heat. In the primary somatosensory cortex most activity in the painful heat task was localized to area 1, where the motor and vibratory task activities were also coincident. The study also indicates that the functional connectivity across multiple cortical regions reorganizes dynamically with each task.
在九名正常受试者中,研究了因右手受到热痛刺激而在对侧大脑中三分之一区域产生的皮质活动,并将其与使用同一身体部位进行振动触觉和运动任务时的激活情况进行了比较。利用多层回波平面功能磁共振成像(fMRI)和表面线圈来显示皮质活动。基于个体受试者活动图和组平均活动图对皮质活动进行了分析。结果显示,在所研究的三个任务和皮质区域中,激活情况存在显著差异。该研究表明,功能磁共振成像能够在解剖细节上检查参与疼痛感知的皮质网络,这是其他脑成像技术所无法做到的,并且表明这种疼痛感知的皮质网络与触觉感知和运动执行的网络有共同的组成部分。然而,热痛感知网络也有其独特的组成部分。独特激活的区域位于次级体感区、脑岛和后扣带回皮质。后扣带回皮质的活动区域,在猴子中,接收来自丘脑后内侧和外侧核的伤害性输入,而这些核又是脊髓丘脑束终末的靶点。在热痛任务中,初级体感和运动皮质区域的离散细分也被激活,显示出与其他两个任务重叠程度的区域依赖性差异。在初级运动皮质内,手部区域在刺激为热痛的任务中优先活跃。在初级体感皮质中,热痛任务中的大部分活动局限于1区,运动和振动任务的活动也在此区域重合。该研究还表明,多个皮质区域之间的功能连接会随着每个任务动态重组。