Synaptic Plasticity in Hebbian Cell Assemblies

描述（由申请人提供）：Donald O. Hebb设想了细胞组装——一个小网络，其神经元以固定的顺序放电——来代表记忆痕迹。这些细胞组合被认为是在许多实验准备中观察到的持续活动模式的基础。然而，目前尚不清楚这些组装体是如何从一群发育中的神经元中无中生有地发展起来的，以及组装体在出现后如何保持稳定性。第一个问题直接关系到记忆痕迹是如何在大脑中出现的。第二个问题与癫痫直接相关，癫痫是一种以神经网络不稳定、过度兴奋为特征的病理。大鼠海马培养为研究这些问题提供了一个模型系统。除了是一个高度可处理的系统，它支持混响电路的自发发展，细胞组装的标志。使用该系统与穿孔膜片钳记录相结合，我将检查活动依赖性突触可塑性和Hebbian细胞组装之间的相互关系。

DESCRIPTION (provided by applicant): Donald O. Hebb conceived of the cell assembly - a small network whose neurons fire in stereotyped sequences - to represent a memory trace. These cell assemblies are believed to underlie persistent activity patterns observed in many experimental preparations. However, it is unknown how these assemblies develop ex nihilo from a population of developing neurons, and how an assembly can retain stability once it emerges. The first of these questions bears directly on how memory traces can emerge in the brain. The second question is of direct relevance to epilepsy, a pathology characterized by unstable, hyperexcitable neuronal networks. Rat hippocampal culture provides a model system for studying these questions. In addition to being a highly tractable system, it supports the spontaneous development of reverberatory circuits, a hallmark of cell assemblies. Using this system in combination with perforated patch clamp recordings, I will examine the reciprocal relationship between activity-dependent synaptic plasticity and Hebbian cell assemblies.