Hu Guyue, Huang Xuhui, Jiang Tianzi, Yu Shan
Brainnetome Center, Institute of Automation, Chinese Academy of Sciences, Beijing, China.
National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing, China.
Front Physiol. 2019 Feb 28;10:113. doi: 10.3389/fphys.2019.00113. eCollection 2019.
The prefrontal cortex (PFC), which plays key roles in many higher cognitive processes, is a hierarchical system consisting of multi-scale organizations. Optimizing the working state at each scale is essential for PFC's information processing. Typical optimal working states at different scales have been separately reported, including the dopamine-mediated inverted-U profile of the working memory (WM) at the system level, critical dynamics at the network level, and detailed balance of excitatory and inhibitory currents (E/I balance) at the cellular level. However, it remains unclear whether these states are scale-specific expressions of the same optimal state and, if so, what is the underlying mechanism for its regulation traversing across scales. Here, by studying a neural network model, we show that the optimal performance of WM co-occurs with the critical dynamics at the network level and the E/I balance at the level of individual neurons, suggesting the existence of a unified, multi-scale optimal state for the PFC. Importantly, such a state could be modulated by dopamine at the synaptic level through a series of U or inverted-U profiles. These results suggest that seemingly different optimal states for specific scales are multi-scale expressions of one condition regulated by dopamine. Our work suggests a cross-scale perspective to understand the PFC function and its modulation.
前额叶皮层（PFC）在许多高级认知过程中发挥着关键作用，它是一个由多尺度组织构成的层级系统。优化每个尺度上的工作状态对于PFC的信息处理至关重要。不同尺度下典型的最优工作状态已分别被报道，包括系统层面上多巴胺介导的工作记忆（WM）的倒U型曲线、网络层面的临界动力学以及细胞层面兴奋性和抑制性电流的详细平衡（E/I平衡）。然而，这些状态是否是同一最优状态的尺度特异性表达，以及如果是这样，其跨尺度调节的潜在机制是什么，仍不清楚。在这里，通过研究一个神经网络模型，我们表明WM的最优性能与网络层面的临界动力学以及单个神经元层面的E/I平衡同时出现，这表明PFC存在一个统一的多尺度最优状态。重要的是，这样一种状态可以在突触层面通过一系列U型或倒U型曲线被多巴胺调节。这些结果表明，特定尺度下看似不同的最优状态是由多巴胺调节的一种状态的多尺度表达。我们的工作为理解PFC功能及其调节提供了一个跨尺度的视角。
