Watanabe Shigeru
Department of Psychology, Keio University, Tokyo, Japan.
Rev Neurosci. 2006;17(1-2):29-41. doi: 10.1515/revneuro.2006.17.1-2.29.
Pigeons were trained on a spatial discrimination task using a repeated acquisition procedure. In this procedure, the pigeons were trained to discriminate between the positions of three keys. One of them was designated the correct key. When the subjects reached the criterion, the discrimination task was changed, with one of two previously incorrect keys now being made the correct key. This procedure was repeated at least 15 times. Then, lesions to the whole hippocampus, the medial hippocampus or to the lateral hippocampus were made by injections of ibotenic acid (Experiment 1). Only the subjects with damage to the whole hippocampus showed deficits in learning after the lesions. The deficits were similar to those caused by aspiration lesions /37/. Knife cuts separating the medial and lateral hippocampi were made in Experiment 2. The subjects did not show deficits in the spatial discrimination task after the sections. Although studies of the connectivity in the avian hippocampus suggested functional differences between the medial and lateral hippocampi, the present results show that pigeons can learn spatial discrimination with the medial and lateral parts of hippocampus separated.
鸽子通过重复习得程序接受空间辨别任务训练。在此程序中，鸽子被训练区分三个按键的位置。其中一个被指定为正确按键。当受试者达到标准时，辨别任务发生改变，之前两个错误按键中的一个现在变为正确按键。此程序至少重复15次。然后，通过注射鹅膏蕈氨酸对整个海马体、内侧海马体或外侧海马体进行损伤（实验1）。只有整个海马体受损的受试者在损伤后表现出学习缺陷。这些缺陷与抽吸损伤造成的缺陷相似/37/。在实验2中，进行了将内侧和外侧海马体分离的刀切手术。手术后，受试者在空间辨别任务中未表现出缺陷。尽管对鸟类海马体连接性的研究表明内侧和外侧海马体存在功能差异，但目前的结果表明，鸽子在海马体的内侧和外侧部分分离的情况下仍能学习空间辨别。
