Sclabassi R J, Hinman C L, Kroin J S, Risch H A
Electroencephalogr Clin Neurophysiol. 1985 May;60(5):444-54. doi: 10.1016/0013-4694(85)91019-3.
The effects of prior input on afferent activity in the somatosensory system of the cat have been studied using both twin-pulse experiments and random stimulus trains for which evoked activity is characterized by a set of mathematical functions known as kernels. The kernels quantitatively characterize transformational processes occurring in the system. The first-order kernel is analogous to a classical averaged evoked potential, but to temporally interacting stimuli; the second-order kernel may be likened to a generalized recovery function. Responses to superficial radial nerve stimulation were obtained at sensory (S1) cortex, thalamic n. ventralis posterolateralis (VPL), and the nucleus cuneatus of the dorsal column nuclei (DCN). Comparison of first-order kernels with averaged evoked potentials showed good agreement in chronic awake, chronic anesthetized, and acute anesthetized animals. Second-order kernels indicated complex interactions with an overall depression of subsequent response amplitudes. Comparison between second-order kernels and the results of the two-pulse experiments at both S1 cortex and VPL showed good agreement for early latency response components, but significant deviations for later components suggest higher than second-order non-linearities for this system.
利用双脉冲实验和随机刺激序列，研究了先前输入对猫体感系统传入活动的影响，其中诱发活动由一组称为核的数学函数来表征。这些核定量地描述了系统中发生的转换过程。一阶核类似于经典的平均诱发电位，但针对时间上相互作用的刺激；二阶核可类比为广义恢复函数。在感觉（S1）皮层、丘脑腹后外侧核（VPL）和背柱核（DCN）的楔束核记录到了对桡神经浅支刺激的反应。在慢性清醒、慢性麻醉和急性麻醉动物中，一阶核与平均诱发电位的比较显示出良好的一致性。二阶核表明存在复杂的相互作用，随后的反应幅度总体下降。在S1皮层和VPL处，二阶核与双脉冲实验结果的比较显示，早期潜伏期反应成分具有良好的一致性，但后期成分的显著偏差表明该系统存在高于二阶的非线性。
