Neural network organization of the cognitive map

本研究的目的是研究与空间记忆或情景记忆相关的功能性神经元组织，并进一步确定这些变化是否依赖于部位（海马体vs新皮层）和时间（短期vs长期）。我们实验室之前的研究表明，对于空间任务，海马体中存在一种集群型神经元组织。第一项研究旨在确定情景记忆是否也存在类似的组织。我们训练小鼠（n=5）在情景记忆任务中执行80%的标准，而对照小鼠（n=4）随机检索食物（无记忆需求）。然后对大脑进行免疫组织化学处理，以检测活性依赖性即刻早期基因zif268。对结果的初步分析看起来很有希望。我们目前正在重复这个实验，以增加受试者的数量，并获得更确凿的结果。对于情景记忆，海马体最初参与（24小时），而在更长的时间间隔（30天），新皮质结构被激活。在完成上述研究后，我们将进行第二个实验，以确定空间记忆的长期储存是否也依赖于新皮层结构的激活。

The aim of the proposed studies was to investigate functional neuronal organization related to either spatial or episodic memory and to further determine whether these changes are site- (hippocampus vs neocortex) and time- (short- vs long-term) dependent. Previous studies from our laboratory demonstrated that for a spatial task, there is a cluster-type neuronal organization that occurs in the hippocampus. The first study was aimed at determining whether a similar organization also exists for episodic memory. We trained mice (n=5) to perform to 80% criterion in an episodic memory task, while control mice (n=4) retrieved food randomly (no memory demand). The brains were then processed for immunohistochemistry for the activity-dependent immediate-early gene zif268. Preliminary analysis of the results appear very promising. We are currently replicating this experiment to increase the number of subjects and to obtain more conclusive results. For episodic memory, the hippocampus is initially involved (24h) while at longer time intervals (30d) neocortical structures are activated. At the completion of the above study we will perform a second experiment to determine whether the long-term storage of spatial memory is also dependent on activation of neocortical structures.