Pathway-dependent regulation of sleep dynamics in a network model of the sleep-wake cycle
Pathway-dependent regulation of sleep dynamics in a network model of the sleep-wake cycle
复制标题
睡眠-觉醒周期网络模型中睡眠动态的通路依赖性调节
DOI：
10.1101/705822
复制
发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Héricé C
中科院分区：
文献类型：
--
作者：
Héricé C
睡眠是动物王国中一个基本的自我平衡过程。虽然不同的大脑区域和细胞类型参与了睡眠-觉醒周期的调节，但目前仍不清楚神经群体之间的不同途径如何对其调节做出贡献。在这里，我们解决这个问题，通过研究一个简化的网络模型突触权重操纵的行为。我们的模型由兴奋性和抑制性突触连接的三个神经群体组成。每个种群的活动由一个确定网络状态的发射率模型来描述。即觉醒，快速眼动（REM）睡眠或非REM（NREM）睡眠。通过系统地操纵每个通路的突触权重，我们表明，即使是这个简化的模型也表现出非平凡的行为：例如，唤醒促进人口不仅有助于唤醒的诱导和维持，而且有助于睡眠诱导。虽然快速眼动睡眠促进群体的反复兴奋性连接对于快速眼动睡眠的发生是必不可少的，但这种反复连接并不一定有助于快速眼动睡眠的维持。NREM睡眠的持续时间可以通过来自NREM促进群体的通路的突触强度的变化而缩短或延长。在某些情况下，存在影响特定状态的突触强度的最佳范围，这意味着操纵的量，而不仅仅是方向（即，激活或失活），需要加以考虑。这些结果表明，睡眠动力学的通路依赖性调节，并强调了系统水平的定量方法的重要性，睡眠-觉醒调节电路。
Sleep is a fundamental homeostatic process within the animal kingdom. Although various brain areas and cell types are involved in the regulation of the sleep–wake cycle, it is still unclear how different pathways between neural populations contribute to its regulation. Here we address this issue by investigating the behavior of a simplified network model upon synaptic weight manipulations. Our model consists of three neural populations connected by excitatory and inhibitory synapses. Activity in each population is described by a firing-rate model, which determines the state of the network. Namely wakefulness, rapid eye movement (REM) sleep or non-REM (NREM) sleep. By systematically manipulating the synaptic weight of every pathway, we show that even this simplified model exhibits non-trivial behaviors: for example, the wake-promoting population contributes not just to the induction and maintenance of wakefulness, but also to sleep induction. Although a recurrent excitatory connection of the REM-promoting population is essential for REM sleep genesis, this recurrent connection does not necessarily contribute to the maintenance of REM sleep. The duration of NREM sleep can be shortened or extended by changes in the synaptic strength of the pathways from the NREM-promoting population. In some cases, there is an optimal range of synaptic strengths that affect a particular state, implying that the amount of manipulations, not just direction (i.e., activation or inactivation), needs to be taken into account. These results demonstrate pathway-dependent regulation of sleep dynamics and highlight the importance of systems-level quantitative approaches for sleep–wake regulatory circuits.