Boakye Maxwell, Krauss Beth R, Huckins Sean C, Zhang Lin, Szeverenyi Nikolaus M, Hodge Charles J
Department of Neurosurgery, SUNY Upstate Medical University, 750 East Adams Street, Syracuse, NY 13210, USA.
Neurosci Lett. 2002 Mar 15;321(1-2):5-8. doi: 10.1016/s0304-3940(01)02406-5.
This study investigated the effect of hyperoxia on sensorimotorcortical activity resulting from electrical stimulation of the median nerve, using functional magnetic resonance imaging (fMRI). Nine volunteers underwent stimulation at 5 and 100 Hz while breathing 21% FIO(2) (fraction of inspired oxygen) or 100% FIO(2). fMRI data were correlated with a stimulus predictor curve, transformed into Talairach space and averaged by group. Normoxic (21% FIO(2)) and hyperoxic (100% FIO(2)) sensorimotor activation volumes were compared using Student's t-test. There were no significant differences between the primary somatosensory/primary motor/Brodmann area 40 (SI/MI/Ba40) and secondary somatosensory cortex (SII) activation volumes for normoxia and hyperoxia. (P>0.05). There was no difference between SI/MI/Ba40 and SII activations at 5 and 100 Hz. In contrast to results previously reported for primary visual cortex (V1), hyperoxia did not enhance sensorimotor cortical activation in area SI/MI/Ba40 or SII. These results indicate that there is regional heterogeneity of the fMRI response to hyperoxia in the cerebral cortex.
本研究采用功能磁共振成像（fMRI），调查了高氧对正中神经电刺激所产生的感觉运动皮层活动的影响。9名志愿者在呼吸21%氧分数（FIO₂）（吸入氧分数）或100%FIO₂的同时，分别接受5Hz和100Hz的刺激。fMRI数据与刺激预测曲线相关，转换到Talairach空间并按组进行平均。使用学生t检验比较常氧（21%FIO₂）和高氧（100%FIO₂）状态下的感觉运动激活体积。常氧和高氧状态下，初级体感/初级运动/布罗德曼40区（SI/MI/Ba40）和次级体感皮层（SII）的激活体积没有显著差异（P>0.05）。5Hz和100Hz时，SI/MI/Ba40和SII的激活没有差异。与先前关于初级视觉皮层（V1）的报道结果相反，高氧并未增强SI/MI/Ba40或SII区域的感觉运动皮层激活。这些结果表明，大脑皮层对高氧的fMRI反应存在区域异质性。
