Carew T J, Walters E T, Kandel E R
Science. 1981 Jan 30;211(4481):501-4. doi: 10.1126/science.7455692.
Aversive associative learning in Aplysia california survives restraint of the animal and surgical exposure of the central nervous system. The learning is expressed in the intracellularly recorded activity of identified motor neurons mediating three different defensive behaviors: escape locomotion, inking, and siphon withdrawal. In each case, animals that had previously received paired training showed significant facilitation of synaptic input to motor neurons during test stimulation in the presence of the conditioned stimulus. Animals without such training showed no facilitation of input to the motor neurons. Resting potential and input resistance appeared unaffected by conditioning and were not altered by application of the conditioned stimulus. These results show that the conditioned facilitation of defensive responses cannot be explained by subthreshold actions of the conditioned stimulus on the motor neurons and support the hypothesis that Aplysia learn to associate the conditioned stimulus with a fearlike central state.
加利福尼亚海兔的厌恶性联想学习在动物受到约束和中枢神经系统手术暴露的情况下依然存在。这种学习通过细胞内记录的特定运动神经元的活动表现出来，这些运动神经元介导三种不同的防御行为：逃避性运动、喷墨和虹吸管收缩。在每种情况下，先前接受过配对训练的动物在条件刺激存在时的测试刺激期间，对运动神经元的突触输入表现出显著的易化作用。没有接受这种训练的动物对运动神经元的输入没有表现出易化作用。静息电位和输入电阻似乎不受条件作用的影响，也不会因施加条件刺激而改变。这些结果表明，防御反应的条件性易化不能用条件刺激对运动神经元的阈下作用来解释，并支持了海兔学会将条件刺激与类似恐惧的中枢状态联系起来的假说。
