Rappelsberger P, Pockberger H, Petsche H
Neurophysiological Institute, University of Vienna, Austria.
Physiol Meas. 1993 Nov;14 Suppl 4A:A17-20. doi: 10.1088/0967-3334/14/4a/003.
Intracortical evoked potentials after electrical stimulation of the optic nerve were simultaneously recorded from the different layers of the rabbit's visual cortex. The averaged potentials were subjected to current source density analyses. The results show that the first event after the stimulus is a current sink in layer VI according to the excitatory terminations of the specific afferent fibres of the geniculate body. Since the largest part of the specific afferents terminates in layers IV and V, the sink in those layers may be due to excitatory synaptic events there. The corresponding current sources are situated in the upper layers and are most probably passive sources due to the active sinks. This example demonstrates that the generation of intracortical electric potentials can be explained by vertically oriented current dipoles according to the anatomical peculiarities.
在对兔视觉皮层不同层同时记录视神经电刺激后的皮质内诱发电位。对平均电位进行电流源密度分析。结果表明，根据膝状体特定传入纤维的兴奋性终末，刺激后的第一个事件是VI层的电流汇集。由于特定传入纤维的大部分终末位于IV层和V层，这些层中的电流汇集可能是由于那里的兴奋性突触事件。相应的电流源位于上层，很可能是由于活跃的电流汇集而形成的无源电流源。这个例子表明，根据解剖学特点，皮质内电位的产生可以用垂直取向的电流偶极子来解释。
