Neural substrates of visual stimulus-stimulus association in rhesus monkeys
Neural substrates of visual stimulus-stimulus association in rhesus monkeys
复制标题
恒河猴视觉刺激-刺激关联的神经基质
作者：
E. Murray;D. Gaffan;M. Mishkin
恒河猴学会了 10 种视觉刺激-刺激关联，或配对关联。然后，他们接受双侧杏仁核复合体和底层皮质、海马结构和底层皮质的切除，或者两者的结合，或者保留作为未手术的对照。手术或休息后，测试猴子对术前习得的配对联想的保留情况，以及学习相同类型新联想的能力。未手术的对照组和海马切除的猴子几乎立即重新学习了术前训练的配对伙伴组。相比之下，杏仁核被切除的猴子在重新学习方面出现中度迟缓，而杏仁核和海马联合切除的猴子则严重迟缓。当面对新的视觉刺激时，杏仁核切除或海马切除的猴子以与对照组相同的速度学习新的配对伙伴，而联合切除的猴子再次出现严重迟缓。尽管该组中的所有三只动物都能够使用与配对关联任务中使用的相同刺激和相同的心房延迟来执行延迟匹配样本，但只有一只具有组合损伤的猴子能够学习新的刺激-刺激关联与标准，并且只有在广泛的训练之后才能进行。在主要实验结束时，两名未手术的对照接受了鼻皮质的双侧消融。这些猴子在学习新的配对伙伴方面表现出与主要实验中接受杏仁核和海马联合切除的动物相同的难度。结果表明内侧颞叶，特别是鼻皮质，参与刺激-刺激联想记忆的形成。
Rhesus monkeys learned 10 visual stimulus-stimulus association, or paired associates. They then received bilateral removals of either the amygdaloid complex and underlying cortex, the hippocampal formation and underlying cortex, or both combined, or they were retained as unoperated controls. After surgery or rest, the monkeys were tested for their retention of the preoperatively learned set of paired associates, as well as for their ability to learn new associations of the same type. Both unoperated controls and hippocampectomized monkeys relearned the preoperatively trained set of paired associates almost immediately. By contrast, monkeys with amygdala removals were moderately retarded in relearning, and monkeys with combined amygdala and hippocampal ablations were severely retarded. When confronted with new sets of visual stimuli, monkeys with amygdala removals or hippocampal removals learned new sets of paired associates at the same rate as the controls, whereas monkeys with the combined ablation were again profoundly retarded. Only one monkey with the combined lesion was able to learn new stimulus-stimulus associations to criterion, and then only after extensive training, despite the ability of all three animals in this group to perform delayed matching-to-sample with the same stimuli and the same intraatrial delays as those used in the paired associate task. At the end of the main experiment, two of the unoperated controls received bilateral ablations of the rhinal cortex. These monkeys showed the same level of difficulty in learning new paired associates as the animals in the main experiment that had received the combined amygdala plus hippocampal ablations. The results implicate the medial temporal lobe, and particularly the rhinal cortex, in the formation of stimulus- stimulus associative memories.