arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1708.04543q-bio.NCphysics.bio-ph
收藏

无标度神经元网络中脉冲发放时间依赖的可塑性对随机爆发同步的影响

Effect of Spike-Timing-Dependent Plasticity on Stochastic Burst Synchronization in A Scale-Free Neuronal Network

Sang-Yoon Kim, Woochang Lim

摘要:

我们考虑一个兴奋性人口的阈下Izhikevich神经元,不能火自发无噪声。当耦合强度超过阈值时,单个神经元表现出噪声诱导的爆发。这种神经元群体具有由尖峰定时依赖可塑性(STDP)控制的自适应动态突触强度。在没有STDP的情况下,噪声诱导的阈下神经元突发之间的随机突发同步(SBS)以前被发现发生在大范围的中间噪声强度。在这里,我们研究了添加剂STDP对SBS的影响,通过改变噪声强度$D$的Barabási-Albert无标度网络(SFN)的对称优先连接的情况下。这种类型的SFN表现出幂律度分布,因此它变成具有几个“枢纽”的非均匀SFN(即,超级连接节点)。发现突触可塑性中“马太”效应的发生是由于正反馈过程。好的突发同步通过突触强度的长时程增强(LTP)变得更好,而坏的突发同步通过长时程抑制(LTD)变得更糟。因此,通过改变$D$,发生向SBS的阶梯状快速转变,与不存在STDP时相对平滑的转变相反。在添加剂STDP的存在下,我们还研究了网络结构对固定$D$的SBS的影响。突触强度的LTP和LTD的出现详细研究通过微观研究的基础上的前和突触后神经元的爆发开始时间之间的时间延迟的分布和突触前和突触后的IIBR(瞬时个别爆发率)之间的配对相关性。最后,一个乘法STDP的情况下(取决于状态)也进行了研究,在比较添加剂STDP的情况下(独立的状态)。

英文摘要:

We consider an excitatory population of subthreshold Izhikevich neurons which cannot fire spontaneously without noise. As the coupling strength passes a threshold, individual neurons exhibit noise-induced burstings. This neuronal population has adaptive dynamic synaptic strengths governed by the spike-timing-dependent plasticity (STDP). In the absence of STDP, stochastic burst synchronization (SBS) between noise-induced burstings of subthreshold neurons was previously found to occur over a large range of intermediate noise intensities. Here, we study the effect of additive STDP on the SBS by varying the noise intensity $D$ in the Barabási-Albert scale-free network (SFN) for the case of symmetric preferential attachment. This type of SFN exhibits a power-law degree distribution, and hence it becomes an inhomogeneous one with a few "hubs" (i.e., super-connected nodes). Occurrence of a "Matthew" effect in synaptic plasticity is found to occur due to a positive feedback process. Good burst synchronization gets better via long-term potentiation (LTP) of synaptic strengths, while bad burst synchronization gets worse via long-term depression (LTD). Consequently, a step-like rapid transition to SBS occurs by changing $D$, in contrast to a relatively smooth transition in the absence of STDP. In the presence of additive STDP, we also investigate the effects of network architecture on the SBS for a fixed $D$. Emergences of LTP and LTD of synaptic strengths are investigated in details via microscopic studies based on both the distributions of time delays between the burst onset times of the pre- and the post-synaptic neurons and the pair-correlations between the pre- and the post-synaptic IIBRs (instantaneous individual burst rates). Finally, a multiplicative STDP case (depending on states) is also investigated in comparison with the additive STDP case (independent of states).

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑