Seitz R J, Roland P E
PET-Laboratory, Karolinska Institute, Stockholm, Sweden.
Acta Neurol Scand. 1992 Jul;86(1):60-7. doi: 10.1111/j.1600-0404.1992.tb08055.x.
The aim of this study was to examine the hypothesis, if the activation of some cerebral structures due to physiological stimulation is accompanied by deactivations of other structures elsewhere in the brain. A vibratory stimulus was applied to the right hand palm of healthy volunteers and the regional cerebral blood flow (rCBF) and regional cerebral oxygen metabolism (rCMRO2) were measured with positron emission tomography (PET). Regional analysis and voxel-by-voxel plots indicated that the stimulation induced increases and decreases of the rCBF were coupled to increases and decreases of the rCMRO2. The increases were localized in the left primary somatosensory area (SI), the left secondary somatosensory area (SII), the left retroinsular field (RI), the left anterior parietal cortex, the left primary motor area (MI), and the left supplementary motor area (SMA). The decreases occurred bilaterally in the superior parietal cortex, in paralimbic association areas, and the left globus pallidus. The increases and decreases of the rCBF and rCMRO2 were balanced in such a way that the mean global CBF and CMRO2 did not change compared with rest. We conclude that the decreases of the cerebral oxidative metabolism indicated regional depressions of synaptic activity.
生理刺激引起某些脑结构激活的同时，脑内其他部位的结构是否会出现失活。对健康志愿者的右手手掌施加振动刺激，并用正电子发射断层扫描（PET）测量局部脑血流量（rCBF）和局部脑氧代谢率（rCMRO2）。区域分析和逐像素绘图表明，刺激引起的rCBF增加和减少与rCMRO2的增加和减少相关联。增加的区域位于左侧初级体感区（SI）、左侧次级体感区（SII）、左侧岛后区（RI）、左侧顶叶前部皮质、左侧初级运动区（MI）和左侧辅助运动区（SMA）。减少发生在双侧顶上叶皮质、边缘旁联合区和左侧苍白球。rCBF和rCMRO2的增加和减少相互平衡，使得与静息状态相比，平均全脑CBF和CMRO2没有变化。我们得出结论，脑氧化代谢的减少表明突触活动出现了局部抑制。
