Neave N, Nagle S, Sahgal A, Aggleton J P
Department of Psychology, University of Durham, UK.
Behav Brain Res. 1996 Oct;80(1-2):75-85. doi: 10.1016/0166-4328(96)00022-8.
Rats received one of three different surgeries in which radiofrequency lesions were made in the cingulum bundle. These consisted of either: (i) two pairs of bilateral lesions at the mid and posterior levels of the tract (M + PCB, n = 9); (ii) a single pair of bilateral lesions at the posterior level of the tract (PCB, n = 5); or (iii) a single lesion in each hemisphere, one at a posterior level the other at a mid level (CCB, n = 6). Twelve other animals acted as surgical controls (SHAM). None of the groups of animals with cingulum bundle lesions was impaired on either the acquisition or performance of an automated delayed nonmatching-to-position task in an operant chamber. In fact, following combination of the three cingulum bundle groups it was found that the lesions resulted in a small, but significant improvement in performance of this task when compared with the SHAM animals. All three groups with tract lesions were, however, impaired on an alternation task in a T-maze. This double dissociation between the two tests of spatial working memory, coupled with the comparable scores of the three lesion groups, is seen as showing that the cingulum bundle is part of a neuroanatomical circuit subserving aspects of allocentric spatial memory. The relative mildness of the alternation deficit in the present study also suggests that the bundle must be completely destroyed bilaterally to produce a pronounced deficit.
大鼠接受了三种不同手术中的一种，在扣带束中制造射频损伤。这些手术包括：(i) 在束的中部和后部水平进行两对双侧损伤（M + PCB，n = 9）；(ii) 在束的后部水平进行一对双侧损伤（PCB，n = 5）；或(iii) 在每个半球进行单个损伤，一个在后部水平，另一个在中部水平（CCB，n = 6）。另外12只动物作为手术对照（假手术组）。扣带束损伤的动物组在操作箱中的自动延迟位置不匹配任务的习得或表现上均未受损。事实上，将三个扣带束组合并后发现，与假手术动物相比，损伤导致该任务的表现有小幅但显著的改善。然而，所有三个有束损伤的组在T迷宫中的交替任务上均受损。空间工作记忆的这两项测试之间的这种双重分离，再加上三个损伤组的可比分数，被视为表明扣带束是服务于以自我为中心的空间记忆方面的神经解剖回路的一部分。本研究中交替缺陷的相对轻微性还表明，必须双侧完全破坏该束才能产生明显的缺陷。
