Department of Psychology, University of California, Riverside, Riverside, CA 92521, USA.
Neuroscience Program, University of California, Riverside, Riverside, CA 92521, USA.
Cell Rep. 2024 Nov 26;43(11):114926. doi: 10.1016/j.celrep.2024.114926. Epub 2024 Oct 30.
Understanding how cortical network dynamics support learning is a challenge. This study investigates the role of local neural mechanisms in the prefrontal cortex during contingency judgment learning (CJL). To better understand brain network mechanisms underlying CJL, we introduce ambiguity into associative learning after fear acquisition, inducing a generalized fear response to an ambiguous stimulus sharing nontrivial similarities with the conditioned stimulus. Real-time recordings at single-neuron resolution from the prelimbic (PL) cortex show distinct PL network dynamics across CJL phases. Fear acquisition triggers PL network reorganization, led by a disambiguation circuit managing spurious and predictive relationships during cue-danger, cue-safety, and cue-neutrality contingencies. Mice with PL-targeted memory deficiency show malfunctioning disambiguation circuit function, while naive mice lacking unconditioned stimulus exposure lack the disambiguation circuit. This study shows that fear conditioning induces prefrontal cortex cognitive map reorganization and that subsequent CJL relies on the disambiguation circuit's ability to learn predictive relationships.
理解皮质网络动力学如何支持学习是一个挑战。本研究调查了前额叶皮层在条件判断学习(CJL)过程中局部神经机制的作用。为了更好地理解 CJL 背后的大脑网络机制,我们在获得恐惧后在联想学习中引入了模糊性,从而对与条件刺激有实质性相似之处的模糊刺激产生普遍的恐惧反应。来自前额叶皮层(PL)的单神经元分辨率的实时记录显示,在 CJL 阶段,PL 网络动态存在明显差异。恐惧获得引发了 PL 网络重组,由一个去模糊电路领导,该电路在线索危险、线索安全和线索中性的情况下管理虚假和预测关系。PL 靶向记忆缺陷的小鼠表现出去模糊电路功能障碍,而没有暴露于非条件刺激的幼稚小鼠则缺乏去模糊电路。本研究表明,恐惧条件作用诱导前额叶皮层认知图重组,随后的 CJL 依赖于去模糊电路学习预测关系的能力。