Port R L, Romano A G, Steinmetz J E, Mikhail A A, Patterson M M
Behav Neurosci. 1986 Oct;100(5):745-52. doi: 10.1037//0735-7044.100.5.745.
The effects of dorsal hippocampal lesions on retention of classical trace conditioned responses were examined using the rabbit nictitating membrane preparation. Animals were trained to criteria and then lesioned either in the cortex or in the hippocampus and the cortex. Hippocampal damage had no effect on the retention of responses but produced significantly longer onset latencies. A control group of hippocampal animals acquired conditioned responses (CRs) at least as quickly as the prelesion subjects, and they also exhibited longer response onset latency. A second experiment evaluated the performance of hippocampal lesioned animals in classical trace conditioning with either a low-intensity periorbital shock or corneal air puff as the unconditioned stimulus (UCS). Hippocampal animals successfully acquired CRs under both conditions but exhibited an alteration of response onset which was dependent on the form of the UCS. Hippocampal animals displayed shorter response onset in the air-puff condition and longer response onset in the shock condition. Cortical animals timed responses consistently regardless of the UCS. These findings strongly suggest that the hippocampus modulates temporal characteristics of learned behavior.
使用兔瞬膜制备方法，研究了背侧海马损伤对经典痕迹条件反应保持的影响。动物训练至标准后，在皮质或海马及皮质进行损伤。海马损伤对反应的保持没有影响，但产生了明显更长的起始潜伏期。一组海马损伤的对照动物获得条件反应（CRs）的速度至少与损伤前的动物一样快，并且它们也表现出更长的反应起始潜伏期。第二个实验评估了海马损伤动物在以低强度眶周电击或角膜吹气作为无条件刺激（UCS）的经典痕迹条件反射中的表现。海马损伤的动物在两种条件下都成功获得了CRs，但表现出反应起始的改变，这取决于UCS的形式。海马损伤的动物在吹气条件下表现出较短的反应起始，在电击条件下表现出较长的反应起始。皮质损伤的动物无论UCS如何，反应计时都一致。这些发现强烈表明海马调节学习行为的时间特征。
