Ion gradient-driven bifurcations of a multi-scale neuronal model
Ion gradient-driven bifurcations of a multi-scale neuronal model
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多尺度神经元模型的离子梯度驱动分叉
DOI：
10.1016/j.chaos.2023.113120
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Weistuch, Corey
中科院分区：
文献类型：
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作者：
Chesebro, Anthony G.;Mujica-Parodi, Lilianne R.;Weistuch, Corey
大脑内的代谢限制经常出现在衰老和疾病的背景下。作为大脑中最大的能量消耗者，当能量供应变得有限时，维持神经元膜电位的离子泵受到的影响最大。为了表征这种限制的影响，我们分析了基于电导的（莫里斯-勒卡）神经质量模型中存在的离子梯度。我们显示的存在和位置的Neimark-Sacker和倍周期分岔的钠，钙，钾的逆转电位，并表明这些分岔形成生理相关的离子梯度变化的界限。在这些范围内，我们展示了梯度去极化如何导致神经活动减少。我们还表明，离子梯度的去极化降低了区域间的一致性，导致在耦合发生的临界点的转变，从而诱导区域之间的同步损失。通过这种方式，我们表明，Larter-Breakspear模型捕获离子梯度的变化存在于微观层面，并传播这些变化的宏观效应，如在人类神经影像学研究中观察到的。
Metabolic limitations within the brain frequently arise in the context of aging and disease. As the largest consumers of energy within the brain, ion pumps that maintain the neuronal membrane potential are the most affected when energy supply becomes limited. To characterize the effects of such limitations, we analyze the ion gradients present in a conductance-based (Morris–Lecar) neural mass model. We show the existence and locations of Neimark–Sacker and period-doubling bifurcations in the sodium, calcium, and potassium reversal potentials and demonstrate that these bifurcations form physiologically relevant bounds of ion gradient variability. Within these bounds, we show how depolarization of the gradients causes decreased neural activity. We also show that the depolarization of ion gradients decreases inter-regional coherence, causing a shift in the critical point at which the coupling occurs and thereby inducing loss of synchrony between regions. In this way, we show that the Larter-Breakspear model captures ion gradient variability present at the microscale level and propagates these changes to the macroscale effects such as those observed in human neuroimaging studies.