Department of Psychiatry, Division of Systems Neuroscience, Columbia University and the Research Foundation for Mental Hygiene, New York State Psychiatric Institute, NY, USA.
Department of Psychiatry, Division of Systems Neuroscience, Columbia University and the Research Foundation for Mental Hygiene, New York State Psychiatric Institute, NY, USA.
Behav Brain Res. 2019 Nov 18;374:112112. doi: 10.1016/j.bbr.2019.112112. Epub 2019 Aug 1.
Anatomical observations, theoretical work and lesion experiments have led to the idea that an important function of the dentate gyrus of the mammalian hippocampus is pattern separation, a neural computation that ensures new memories are encoded without interference from previously stored memories that share similar features. The dentate gyrus also exhibits a unique form of neural plasticity that results from the continuous integration of newly born excitatory granule cells, termed adult hippocampal neurogenesis. However, the manner in which adult neurogenesis contributes to dentate gyrus network activity and computations is incompletely understood. Here, we first describe the prevailing models for the role of adult neurogenesis in dentate gyrus network function and then re-evaluate these models in the light of recent findings regarding the in vivo activity of the dentate gyrus and synaptic interactions of adult born granule cells with local circuit components, as well as, inputs, and outputs of the dentate gyrus. We propose that adult neurogenesis provides flexibility for the dentate gyrus to rapidly generate a context specific, distributed representation of important sensory stimuli such as spatial cues, which ultimately gives rise to behavioral discrimination.
解剖学观察、理论研究和损伤实验提出，哺乳动物海马齿状回的一个重要功能是模式分离，这是一种神经计算，可确保新记忆的编码不会受到与具有相似特征的先前存储记忆的干扰。齿状回还表现出一种独特的神经可塑性，这是由于新生兴奋性颗粒细胞的持续整合，即成年海马神经发生。然而，成年神经发生对齿状回网络活动和计算的贡献方式尚不完全清楚。在这里，我们首先描述了成年神经发生在齿状回网络功能中的作用的流行模型，然后根据最近关于齿状回的体内活动以及成年产生的颗粒细胞与局部回路成分的突触相互作用，以及齿状回的输入和输出的发现，重新评估这些模型。我们提出，成年神经发生为齿状回提供了灵活性，使其能够快速生成重要感觉刺激（如空间线索）的特定于上下文的分布式表示，最终导致行为辨别。
