Kraut M A, Arezzo J C, Vaughan H G
Electroencephalogr Clin Neurophysiol. 1985 Jul;62(4):300-12. doi: 10.1016/0168-5597(85)90007-3.
Flash visual evoked potentials (VEPs) in unanesthetized monkeys were recorded from the cortical surface and from closely spaced intracortical sites together with associated multiple unit activity (MUA). The VEP depth profiles were subjected to current source density (CSD) analysis to delineate the laminar pattern of transmembrane current flows manifested by extracellular source and sinks. The initial surface recorded components (P15 and P18) were generated subcortically within the thalamocortical radiations. The distribution of current sources and sinks associated with two subsequent surface negative components. N24 and N40. demonstrates their generation within laminae IVA and IVCb respectively, both parvocellular thalamorecipient layers. Oscillatory potentials resembling those seen in human VEPs are observed riding on N40; analysis of MUA in conjunction with sources and sinks coincident with these wavelets provides evidence that they derive from both thalamocortical and cortical activity. MUA in the 20-60 msec range shows phasic increases throughout lamina IV, which are maximum in amplitude within lamina IVA. This increased firing is concurrent with the sinks observed within the parvocellular thalamorecipient sublaminae IVCb and IVA. A subsequent component, P65, coincident with a decrease in MUA to below the spontaneous level co-located with a lamina IVCb current source, probably arises from intracortically generated inhibitory activity within IVCb. The next VEP component, a surface negative potential at 95 msec, is coincident with current sources and sinks in lamina III, and is consistent with stellate cell input to supragranular elements. VEP components after N95 are not associated with either MUA or CSD activity and are probably generated in extrastriate cortex. Human counterparts of the simian VEP are proposed.
在未麻醉的猴子中，从皮质表面和紧密间隔的皮质内位点记录闪光视觉诱发电位（VEP），同时记录相关的多单位活动（MUA）。对VEP深度剖面进行电流源密度（CSD）分析，以描绘由细胞外源和汇表现出的跨膜电流流动的层状模式。最初在表面记录的成分（P15和P18）是在丘脑皮质辐射内的皮质下产生的。与随后的两个表面负成分N24和N40相关的电流源和汇的分布分别表明它们在IV A层和IV Cb层内产生，这两层都是小细胞丘脑接受层。在N40上观察到类似于人类VEP中所见的振荡电位；结合与这些小波重合的源和汇对MUA进行分析，提供了它们源自丘脑皮质和皮质活动的证据。20-60毫秒范围内的MUA在整个IV层显示出相位增加，在IV A层内幅度最大。这种放电增加与在小细胞丘脑接受子层IV Cb和IV A内观察到的汇同时出现。随后的成分P65与MUA降至自发水平以下同时出现，与IV Cb层电流源共定位，可能源于IV Cb内皮质内产生的抑制性活动。下一个VEP成分是95毫秒时的表面负电位，与III层中的电流源和汇重合，并且与星状细胞对上颗粒元件的输入一致。N95之后的VEP成分与MUA或CSD活动均无关，可能在纹外皮质产生。本文提出了猴VEP的人类对应物。
