An examination of the spatial working memory deficit following neurotoxic medial dorsal thalamic lesions in rats
An examination of the spatial working memory deficit following neurotoxic medial dorsal thalamic lesions in rats
复制标题
DOI：
10.1016/s0166-4328(98)00033-3
复制
发表时间：
1998-12-01
影响因子：
2.7
通讯作者：
Aggleton, JP
中科院分区：
文献类型：
--
作者：
Hunt, PR;Aggleton, JP
本研究测试了以丘脑背内侧核为中心的神经毒性损伤的大鼠在标准版本和改进版本的八臂径向迷宫测试中的表现。在实验1中，丘脑损伤在获得标准任务时产生了临界性缺陷，但随后在进入前四个手臂后插入延迟时没有影响。同样的病变对T迷宫交替没有影响，但当迷宫内和迷宫外线索相互对立时，它们确实损害了放射臂迷宫的性能。在实验2中，丘脑背内侧的损伤损害了标准的放射臂迷宫任务的获得，但结合实验1和实验2的结果显示，这种获取缺陷仅限于双侧损害延伸到邻近丘脑前核的动物。此外，当任务被修改以比较工作记忆和参考记忆以及增加活动和探索时，背内侧丘脑的损伤扰乱了放射臂迷宫的表现。这些变化与丘脑前部损害无关。最后，丘脑损伤没有影响自发物体识别测试的表现。结论：损毁背内侧核不会破坏空间记忆，但会影响与任务绩效相互作用的其他加工过程。这些因素包括迷宫外线索不能盖过迷宫内线索、活动和探索水平的改变以及持有空间反应的缺陷。(C)1998 Elsevier Science B.V.保留所有权利。
The present study examined the performance of rats with neurotoxic lesions centred in the thalamic nucleus medialis dorsalis on standard and modified versions of the eight arm radial maze test. In Experiment 1, the thalamic lesions produced a borderline deficit in acquisition of the standard task, but subsequently had no effect when a delay was interposed after the first four arms had been entered. The same lesions had no effect on T-maze alternation, but they did impair radial-arm maze performance when intramaze and extramaze cues were set against each other. In Experiment 2, lesions of the dorsomedial thalamus impaired acquisition of the standard radial-arm maze task, but combining the results from Experiments 1 and 2 showed that this acquisition deficit was confined to those animals in which bilateral damage extended into the adjacent anterior thalamic nuclei. In addition, lesions of the dorsomedial thalamus disrupted radial-arm maze performance when the task was modified to compare working memory and reference memory and increased activity and exploration. These changes were not associated with anterior thalamic damage. Finally, the thalamic lesions did not affect performance on a test of spontaneous object recognition. It is concluded that lesions of medialis dorsalis do not disrupt spatial memory but do affect other processes that can interact with task performance. These include a failure of extramaze cues to overshadow intramaze cues, a change in activity and exploration levels and deficits in with-holding spatial responses. (C) 1998 Elsevier Science B.V. All rights reserved.