O'Brien J H, Wilder M B, Stevens C D
J Comp Physiol Psychol. 1977 Aug;91(4):918-29. doi: 10.1037/h0077374.
Single-cell activity was recorded from the postcruciate cortex of acutely prepared cats during a differential classical conditioning procedure. The conditioned stimuli (CS) were hind paw stimuli, and the unconditioned stimulus (US) was pyramidal tract stimulation that produced an antidromic response in the recorded cortical neuron. A control group was also examined in which the pyramidal stimulus was set below the threshold to produce an antidromic response. Clear differential conditioning was found for the experimental group, with antidromic activation of the neuron as the US. There was no evidence of differential conditioning in the control group without antidromic activation. Any activation of orthodromic pathways should have been the same in the control and experimental groups. The absence of conditioning in the control group demonstrated that orthodromic pathways were not contributing to the differential conditioning observed in the experimental group. This indicates that it was activation of the neuron produced by antidromic firing which was important for conditioning. All the evidence suggests that the site of learning was in the cortex. It is concluded that the the role of the US in conditioning may be simply to activate the neuron at an appropriate interval following the CS.
在一个差异经典条件反射程序中，从急性制备的猫的十字后皮质记录单细胞活动。条件刺激（CS）是后爪刺激，非条件刺激（US）是锥体束刺激，该刺激在记录的皮质神经元中产生逆向反应。还检查了一个对照组，其中锥体刺激设置低于产生逆向反应的阈值。对于实验组，发现了明显的差异条件反射，以神经元的逆向激活作为非条件刺激。在没有逆向激活的对照组中没有差异条件反射的证据。在对照组和实验组中，任何顺向通路的激活应该是相同的。对照组中没有条件反射表明顺向通路对实验组中观察到的差异条件反射没有贡献。这表明，对条件反射重要的是由逆向发放产生的神经元激活。所有证据表明，学习部位在皮质。得出的结论是，非条件刺激在条件反射中的作用可能仅仅是在条件刺激之后的适当间隔激活神经元。
