Self-tuning of neural circuits through short-term synaptic plasticity.
Self-tuning of neural circuits through short-term synaptic plasticity.
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DOI：
10.1152/jn.01357.2006
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发表时间：
2007-06
影响因子：
2.5
通讯作者：
David Sussillo;Taro Toyoizumi;W. Maass
中科院分区：
文献类型：
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作者：
David Sussillo;Taro Toyoizumi;W. Maass
大量实验数据表明，皮质神经元网络在没有外部输入的情况下并不是沉默的，而是保持较低的自发放电活动。皮质网络的这一方面可能对其计算功能很重要，但很难在神经元皮质回路模型中重现，因为低活动状态本质上是不稳定的。在这里，我们通过理论分析和广泛的计算机模拟表明，短期突触可塑性赋予皮质回路模型在低活动状态下具有显着的稳定性。这种短期可塑性作为一种稳态机制，尽管外部输入和内部电路特性发生巨大变化，仍能稳定整体活动水平，同时保持对信号的可靠瞬态响应。突触动力学对这种稳定性的贡献可以根据控制理论的一般原理来预测。
Numerous experimental data show that cortical networks of neurons are not silent in the absence of external inputs, but rather maintain a low spontaneous firing activity. This aspect of cortical networks is likely to be important for their computational function, but is hard to reproduce in models of cortical circuits of neurons because the low-activity regime is inherently unstable. Here we show-through theoretical analysis and extensive computer simulations-that short-term synaptic plasticity endows models of cortical circuits with a remarkable stability in the low-activity regime. This short-term plasticity works as a homeostatic mechanism that stabilizes the overall activity level in spite of drastic changes in external inputs and internal circuit properties, while preserving reliable transient responses to signals. The contribution of synaptic dynamics to this stability can be predicted on the basis of general principles from control theory.