Department of Electrical Engineering and Computer Science, University of Liege, Liege, Belgium.
PLoS Comput Biol. 2021 May 18;17(5):e1008997. doi: 10.1371/journal.pcbi.1008997. eCollection 2021 May.
Switches in brain states, synaptic plasticity and neuromodulation are fundamental processes in our brain that take place concomitantly across several spatial and timescales. All these processes target neuron intrinsic properties and connectivity to achieve specific physiological goals, raising the question of how they can operate without interfering with each other. Here, we highlight the central importance of a timescale separation in the activation of sodium and T-type calcium channels to sustain robust switches in brain states in thalamic neurons that are compatible with synaptic plasticity and neuromodulation. We quantify the role of this timescale separation by comparing the robustness of rhythms of six published conductance-based models at the cellular, circuit and network levels. We show that robust rhythm generation requires a T-type calcium channel activation whose kinetics are situated between sodium channel activation and T-type calcium channel inactivation in all models despite their quantitative differences.
脑状态转换、突触可塑性和神经调制是我们大脑中的基本过程,它们在多个时空尺度上同时发生。所有这些过程都针对神经元的内在特性和连接性来实现特定的生理目标,这就提出了一个问题,即它们如何在不相互干扰的情况下进行操作。在这里,我们强调了钠离子和 T 型钙通道激活的时间尺度分离在维持丘脑神经元中大脑状态的稳健转换中的核心重要性,这些转换与突触可塑性和神经调制兼容。我们通过比较六个已发表的基于电导率模型在细胞、电路和网络水平上的稳健性,来量化这种时间尺度分离的作用。我们表明,尽管存在定量差异,但稳健的节律产生需要 T 型钙通道的激活,其动力学位于钠通道激活和 T 型钙通道失活之间。