Kitamura Y, Kakigi R, Hoshiyama M, Koyama S, Nakamura A
Department of Integrative Physiology, National Institute for Physiological Sciences, Okazaki 444, Japan.
Brain Res Cogn Brain Res. 1996 Nov;4(4):275-9. doi: 10.1016/s0926-6410(96)00066-3.
We studied the effects of sleep on somatosensory evoked magnetic fields (SEFs) following median nerve stimulation in normal subjects, to investigate the changes of functional processing of sensory perception in the primary and second sensory cortices (SI and SII). The early components, 1M, 2M and 3M, which were generated in SI contralateral to the stimulated nerve, showed no significant change of latency or amplitude in stage 1 or 2 as compared with those in the awake state. The long-latency response, 4M whose latency was about 100 ms, was significantly enhanced in stage 2. The 4M was considered to be generated in SI and SII in the awake state, but the enhanced 4M in stage 2 was restricted in SI. The 4M(I) generated in SII of the hemisphere ipsilateral to the stimulated nerve, corresponding to 4M in the contralateral hemisphere, was absent during sleep. These findings were probably due to the difference of activities between SI and SII during sleep, that is, an increase of sensitivity to somatosensory stimulation in SI but a decrease or disappearance in SII.
我们研究了正常受试者在正中神经刺激后睡眠对体感诱发电场（SEFs）的影响，以探讨初级和次级感觉皮层（SI和SII）中感觉知觉功能处理的变化。早期成分1M、2M和3M在受刺激神经对侧的SI中产生，与清醒状态相比，在第1阶段或第2阶段其潜伏期或波幅没有显著变化。潜伏期约为100毫秒的长潜伏期反应4M在第2阶段显著增强。4M在清醒状态下被认为在SI和SII中产生，但在第2阶段增强的4M局限于SI。在睡眠期间，受刺激神经同侧半球的SII中产生的对应于对侧半球4M的4M（I）不存在。这些发现可能是由于睡眠期间SI和SII之间活动的差异，即SI对体感刺激的敏感性增加，而SII则降低或消失。
