文献类型：期刊文献

英文题名：A cortical model with multi-layers to study visual attentional modulation of neurons at the synaptic level

作者：Zhang, Tao[1];Pan, Xiaochuan[1];Xu, Xuying[1];Wang, Rubin[1]

机构：[1]East China Univ Sci & Technol, Inst Cognit Neurodynam, Meilong Rd 130, Shanghai, Peoples R China

年份：2019

卷号：13

期号：6

起止页码：579

外文期刊名：COGNITIVE NEURODYNAMICS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000501013000008)】；

基金：This study was funded by National Natural Science Foundation of China (Nos. 11232005, 11472104, 11702096, 11872180) and sponsored by Shanghai Pujiang Program (No. 13PJ1402000).

语种：英文

外文关键词：Visual attention; AMPA and NMDA receptors; Stochastic binding process; Hodgkin-Huxley model

摘要：Visual attention is a selective process of visual information and improves perceptual performance by modulating activities of neurons in the visual system. It has been reported that attention increased firing rates of neurons, reduced their response variability and improved reliability of coding relevant stimuli. Recent neurophysiological studies demonstrated that attention also enhanced the synaptic efficacy between neurons mediated through NMDA and AMPA receptors. Majority of computational models of attention usually are based on firing rates, which cannot explain attentional modulations observed at the synaptic level. To understand mechanisms of attentional modulations at the synaptic level, we proposed a neural network consisting of three layers, corresponding to three different brain regions. Each layer has excitatory and inhibitory neurons. Each neuron was modeled by the Hodgkin-Huxley model. The connections between neurons were through excitatory AMPA and NMDA receptors, as well as inhibitory GABA(A) receptors. Since the binding process of neurotransmitters with receptors is stochastic in the synapse, it is hypothesized that attention could reduce the variation of the stochastic binding process and increase the fraction of bound receptors in the model. We investigated how attention modulated neurons' responses at the synaptic level on the basis of this hypothesis. Simulated results demonstrated that attention increased firing rates of neurons and reduced their response variability. The attention-induced effects were stronger in higher regions compared to those in lower regions, and stronger for inhibitory neurons than for excitatory neurons. In addition, AMPA receptor antagonist (CNQX) impaired attention-induced modulations on neurons' responses, while NMDA receptor antagonist (APV) did not. These results suggest that attention may modulate neuronal activity at the synaptic level.