Connectivity reflects coding: a model of voltage-based STDP with homeostasis
Connectivity reflects coding: a model of voltage-based STDP with homeostasis
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DOI：
10.1038/nn.2479
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发表时间：
2010-03-01
影响因子：
25
通讯作者：
Gerstner, Wulfram
中科院分区：
文献类型：
--
作者：
Clopath, Claudia;Buesing, Lars;Gerstner, Wulfram
皮层的电生理连接模式通常在许多弱连接中具有少数强连接，这些强连接有时是双向的。为了解释这些连接模式，我们创建了一个模型的尖峰时间依赖性可塑性（STDP），其中突触的变化取决于突触前尖峰的到来和突触后膜电位，过滤两个不同的时间常数。我们的模型描述了在STDP实验中观察到的几种非线性效应，以及塑性的电压依赖性。我们发现，在一个模拟的循环网络的尖峰神经元，我们的可塑性规则不仅导致本地化的感受野的发展，但也反映了神经代码的连接模式。对于具有时空输入相关性的时间编码过程，强连接主要是单向的，而在仅具有空间相关性的速率编码输入下，它们是双向的。因此，大脑中不同的连接模式可能反映了不同大脑区域的编码原则;此外，我们的模拟表明可塑性是快速的。
Electrophysiological connectivity patterns in cortex often have a few strong connections, which are sometimes bidirectional, among a lot of weak connections. To explain these connectivity patterns, we created a model of spike timing-dependent plasticity (STDP) in which synaptic changes depend on presynaptic spike arrival and the postsynaptic membrane potential, filtered with two different time constants. Our model describes several nonlinear effects that are observed in STDP experiments, as well as the voltage dependence of plasticity. We found that, in a simulated recurrent network of spiking neurons, our plasticity rule led not only to development of localized receptive fields but also to connectivity patterns that reflect the neural code. For temporal coding procedures with spatio-temporal input correlations, strong connections were predominantly unidirectional, whereas they were bidirectional under rate-coded input with spatial correlations only. Thus, variable connectivity patterns in the brain could reflect different coding principles across brain areas; moreover, our simulations suggested that plasticity is fast.