Vann Seralynne D
School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT, UK.
Eur J Neurosci. 2005 Feb;21(3):820-4. doi: 10.1111/j.1460-9568.2005.03896.x.
The mammillary bodies have long been implicated in spatial memory, and lesions of this structure in rats can impair some spatial memory tasks. The mammillary bodies, however, comprise two main nuclei that have different electrophysiological and anatomical properties. It is therefore possible that they have different functions. The present study determined whether selective lesions of one of these components, the lateral mammillary nucleus, are sufficient to induce spatial memory deficits. While selective lateral mammillary nuclei lesions induced deficits on a working memory task in the water maze, this impairment was milder and not as persistent as that seen with complete mammillary body lesions. Furthermore, lateral mammillary nuclei lesions did not impair T-maze alternation, which is sensitive to complete mammillary body lesions. From these results it appears that lesions confined to the lateral mammillary nuclei are sufficient to produce mild impairments when rapid, new spatial learning is at a premium. At the same time, the remaining mammillary nuclei also contribute to spatial learning, though this may be in a qualitatively different manner.
乳头体长期以来一直被认为与空间记忆有关，大鼠该结构的损伤会损害一些空间记忆任务。然而，乳头体由两个具有不同电生理和解剖学特性的主要核组成。因此，它们可能具有不同的功能。本研究确定了这些组成部分之一——外侧乳头核的选择性损伤是否足以诱发空间记忆缺陷。虽然外侧乳头核的选择性损伤在水迷宫的工作记忆任务中导致了缺陷，但这种损伤比完全乳头体损伤所见的要轻，且不那么持久。此外，外侧乳头核损伤并未损害对完全乳头体损伤敏感的T迷宫交替。从这些结果看来，当快速的新空间学习至关重要时，局限于外侧乳头核的损伤足以产生轻度损伤。同时，其余的乳头核也对空间学习有贡献，尽管这可能是以一种质的不同方式。
