Analysis of dynamic neuronal assemblies for memory processes of stimulus and temporal events

本研究探讨了细胞集合（即具有灵活功能连接的神经元集合群）是否是大脑中记忆信息处理的基本神经元编码。表明细胞组装编码真实性的主要特性是不同组件之间的神经元重叠以及组件内部和组件之间的连接动态。前者可以被检测为单个神经元在处理不同类型信息时的多种功能。单个神经元似乎参与多种信息处理。后者可以通过处理不同类型信息的功能性突触连接的变化来检测。一些被记录的神经元之间的活动相关性似乎在多个信息处理过程中发生了变化。本实验比较了几种不同的记忆过程（任务），包括刺激物的处理和时间事件的处理，并寻找两个主要特性。第一个实验…More ent以大鼠为实验对象，比较刺激的记忆过程（刺激辨别）及其呈现的持续时间（持续辨别）。当大鼠同时完成这两项任务时，海马体区域的多神经元活动被记录和分析。第二个实验以猴子为实验对象，比较了刺激的短期记忆保留过程（延迟匹配到样本的颜色）和呈现的持续时间（延迟匹配到样本的持续时间）。当猴子同时执行这两项任务时，研究人员记录并分析了前额皮质区域的多神经元活动。通过分析单个神经元的活动及其相互之间的活动相关性，所有这些实验都证明了细胞组装编码在刺激和时间事件处理中的两个主要特性。此外，实验还表明，在刺激和时间事件的处理过程中，细胞组装编码的一些不同特征。少

The present research investigated if the cell assembly, i.e., an ensemble population of neurons with flexible functional connections, is the basic neuronal code for information processes of memory in the brain. The main properties indicating the reality of cell-assembly coding are neurons overlapping among different assemblies and connection dynamics within and among the assemblies. The former can be detected as multiple functions of individual neurons in processing different kinds of information. Individual neurons appear to be involved in multiple information-processes. The latter can be detected as changes of functional synaptic connections in processing different kinds of information. Correlations of activity among some of the recorded neurons appear to change in multiple information-processes. The present experiments compared several different memory processes (tasks), including processings of stimulus and temporal events and searched for the two main properties. The first experim … More ent used rats as subjects and compared memory processes of stimulus (stimulus discrimination) and its presented duration (duration discrimination). Multineuronal activities from the hippocampal areas were recorded and analyzed when the rats were performing the both tasks. The second experiment used monkeys as subjects and compared short-term retention processes of memory for stimulus (delayed matching-to-sample of color) and its presented duration (delayed matching-to-sample of duration). Multineuronal activities from the prefrontal cortical areas were recorded and analyzed when the monkeys were performing the both tasks. By analyzing the individual neuronal activities and their activity correlations with each others, all theses experiments are demonstrating the two main properties of cell-assembly coding in processings of stimulus and temporal events. Also, the experiments are suggesting some different features of cell-assembly coding between the processings of stimulus and temporal events. Less