Emergent spatial synaptic structure from diffusive plasticity.
Emergent spatial synaptic structure from diffusive plasticity.
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来自扩散可塑性的新兴空间突触结构。
DOI：
10.1111/ejn.13279
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Sweeney Y
中科院分区：
文献类型：
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作者：
Sweeney Y
一些神经递质可以自由扩散穿过细胞膜，影响邻近的神经元，而不管它们的突触耦合。这提供了一种替代突触传递的神经通信手段，可以影响神经网络处理信息的方式。在这里，我们问是否扩散性神经传递也可以影响突触连接的网络进行可塑性的结构。我们提出了一种形式的赫布突触可塑性，这是介导的扩散神经递质。每当通过我们提出的机制在单个神经元处修改突触时，连接到相邻神经元的突触中会发生类似但较小的修改。在基于速率的神经元网络中探索了这种扩散可塑性的影响。这导致了网络突触连接中空间结构的出现。我们发现，这种空间结构可以与突触连接中的其他形式的结构共存，例如与响应相关外部驱动而形成的强烈互连的神经元组共存。最后，我们探讨了在一个简单的前馈网络模型的感受野发展的扩散可塑性。我们发现，正如在感觉皮层中广泛观察到的那样，由于扩散，我们网络中神经元的首选刺激身份在空间上变得相关。我们提出的扩散可塑性机制提供了一个有效的机制，产生这些空间相关性的刺激偏好，可以灵活地与其他形式的突触组织。
Some neurotransmitters can diffuse freely across cell membranes, influencing neighbouring neurons regardless of their synaptic coupling. This provides a means of neural communication, alternative to synaptic transmission, which can influence the way in which neural networks process information. Here, we ask whether diffusive neurotransmission can also influence the structure of synaptic connectivity in a network undergoing plasticity. We propose a form of Hebbian synaptic plasticity which is mediated by a diffusive neurotransmitter. Whenever a synapse is modified at an individual neuron through our proposed mechanism, similar but smaller modifications occur in synapses connecting to neighbouring neurons. The effects of this diffusive plasticity are explored in networks of rate‐based neurons. This leads to the emergence of spatial structure in the synaptic connectivity of the network. We show that this spatial structure can coexist with other forms of structure in the synaptic connectivity, such as with groups of strongly interconnected neurons that form in response to correlated external drive. Finally, we explore diffusive plasticity in a simple feedforward network model of receptive field development. We show that, as widely observed across sensory cortex, the preferred stimulus identity of neurons in our network become spatially correlated due to diffusion. Our proposed mechanism of diffusive plasticity provides an efficient mechanism for generating these spatial correlations in stimulus preference which can flexibly interact with other forms of synaptic organisation.