循经感传过程中体觉系统中枢部位机能活动特点的观察

本文以短潜伏期皮层体觉诱发电位(SEP)为指标,对感传过程中皮层体觉区机能活动的特点进行了观察。观察对象为10名循经感传显著者和16名无感传者。以矩形波脉冲刺激侠溪或合谷穴,从对侧头皮体觉区下肢、上肢和头面部三个投射点引导 SEP,观察到针刺侠溪穴时无感传者 SEP C_2的振幅按下肢、上肢和面部三个投射点依次递减。针刺合谷时上肢投射点的 C_2振幅较下肢和面部者高,形成中间高两侧低的空间分布特点。而感传显著者,无论是针刺侠溪穴还是合谷穴 SEP C_2的振幅在三个投射点基本相同。结果提示,针刺时循经感传显著者的 S_1区各投射点出现了比较广泛的兴奋过程。

OBSERVATION ON THE FUNCTIONAL CHARACTERISTICS OF CORTICAL SOMATOSENSORY AREA DURING THE ADVANCE OF THE PROPAGATED SENSATION ALONG MERIDIANS

It is still not clear what role is played by cortical somatosensory system during the advance of propagated sensation along meridians (PSM).In this paper the short-latent somatosensory evoked potential (SLSEP) was taken as an indication to observe the characteristics of functional activity in cortical soma- tosensory area I (SI) during the advance of PSM. The observation was preformed on 10 subjects with marked PSM,which were clear and kept stable.Sixteen subjects without SPM were taken as cont- rol.Electrical stimulation was delivered to the acupoint Jiaxi (GB43) or Hegu (LI4).The SLSEP were recorded simultaneously from 3 scalp points corres- ponding to the representative areas of foot,arm and face contralateral to the stimulated side.The results are shown as follows. When Jiaxi was stimulated,the amplitudes of SLSEP component C_2 (P_(45)- N_(55)) from above three scalp points in subjects without PSC were 0.85±0.17, 0.51±0.11 and 0.31±0.07μv respectively.The amplitude was largest in the foot representative area,but attenuated successively in arm and face areas and a stair-shaped distributiou was thus formed.During stimulating the acupoint Hegu (LI4) the amplitude of SLSEP component C_2 (P_(25)-N_(55)) from the repre- sentative area of arm in subjects without PSM was larger than that from the represeutative areas of foot and face,and a distribution with high-medium and low-bilateral character was shaped.However,no matter whether stimulating Jiaxi or Hegu the amplitude of SLSEP C_2 in subjects with marked PSM was nearly the same from three scalp points. The results suggest that the extensive excitation appeared in various repre- sentative areas of S1 in subjects with marked PSM and they might be more su- sceptible to the stimulation of acupoints.Perhaps,this is one of the favoura- ble condition for the formation of PSM.