Ladds A, Branston N M, Vajda J, McGillicuddy J E, Symon L
Gough-Cooper Department of Neurological Surgery, Institute of Neurology, London, U.K.
Electroencephalogr Clin Neurophysiol. 1988 May-Jun;71(3):233-40. doi: 10.1016/0168-5597(88)90008-1.
Experiments have been performed to produce localized thalamic ischaemia in baboons anaesthetised with alpha-chloralose. Somatosensory evoked potentials to median nerve stimulation were recorded in the medial lemniscus, VPL of thalamus and the primary somatosensory cortex. Local blood flow was also recorded by the hydrogen clearance technique in these regions. The early potential recorded in thalamus has been shown to be generated from 3 sources: (i) a positivity generated outside the VPL, (ii) local wavelets, most likely from synaptic activity close to the recording electrode, and (iii) a local overall negativity. The first of these potentials alone remains after thalamic ischaemia. It arises below the level of the thalamus, being very likely generated by the afferent volley in the medial lemniscus, and is seen in the surface-recorded response as the early component P8 (corresponding to P15 in the human).
实验已在使用α-氯醛糖麻醉的狒狒身上进行，以制造局部丘脑缺血。记录了在内侧丘系、丘脑腹后外侧核（VPL）和初级体感皮层中对正中神经刺激的体感诱发电位。这些区域的局部血流也通过氢清除技术进行了记录。丘脑记录到的早期电位已被证明由3个来源产生：（i）VPL外部产生的正电位，（ii）局部小波，很可能来自靠近记录电极的突触活动，以及（iii）局部整体负电位。丘脑缺血后仅保留这些电位中的第一个。它出现在丘脑水平以下，很可能由内侧丘系中的传入冲动产生，并且在表面记录的反应中表现为早期成分P8（相当于人类的P15）。
