各位老师,您好:
由实验室吴思老师邀请了上海交通大学特别研究员周栋焯博士来实验室做报告。报告信息如下,欢迎感兴趣的老师和同学来听。
报告时间:5月17日上午10:00
报告地点:英东楼422
报告题目:Neuronal dynamics from dendritic integration to population responses
报告摘要: In this talk, I will present our modeling work about neuronal dynamics in comparison with experimental results including (1) How a single neuron integrates excitatory and inhibitory inputs from other neurons in the cortical network, and (2) How population neurons emerge spatiotemporal activities in response to some simple external stimulus. The first part discusses a simple arithmetic rule recently discovered in experiments as $V^{Exp}_S≈V^{Exp}_E + V^{Exp}_I + kV^{Exp}_E V^{Exp}_I$ , where V^{Exp}_S, V^{Exp}_E and V^{Exp}_I are the amplitude of the summed somatic potential (SSP), the excitatory postsynaptic potential (EPSP) and the inhibitory postsynaptic potential (IPSP) measured at the time when the EPSP reaches its peak value. In addition, k is defined as the shunting coefficient which only depends on the spatial location of excitatory and inhibitory inputs on the dendrite and is independent of the amplitude of EPSP and IPSP. We demonstrate both theoretically and numerically that the above dendritic integration rule can be explained by sub-threshold membrane potential dynamics as characterized in the conductance-based integrate-and-fire (I&F) model. In order to account for the spatial dependence of the shunting coefficient k, we propose a dendritic-integration-rule-based integrate-and-fire (DIF) model. Our analytical and numerical results show that this model is able to capture many experimental observations. The second part discusses how we use a large-scale conductance-based, integrate-and-fire neuronal network model in V1 to investigate the spatiotemporal activities of population neurons in response to some simple Garbor stimulus and compared our simulation results to the experimental observations. Our model incorporates both isotropic local couplings of AMPA and GABA, in addition, we model the lateral orientation-specific long-range connections by a slow NMDA component. From the analysis of both experimental observations and our numerical results, we demonstrate that the time scale and the special scale of NMDA component play an essential role in terms of special-temporal patterns and also the cortical correlation structures.
报告人简介:
周栋焯,分别于2002年与2007年获北京大学数学科学学院学士学位与博士学位,博士期间主要研究方向是高分子流体的多尺度建模与计算,2007年至2009年在访问纽约大学库朗研究所期间,研究方向转为大脑神经科学中的数学建模和科学计算,并于2010年加入上海交通大学,任特别研究员。目前主要研究兴趣是:生物及物理中的应用数学问题,如高分子流体的多尺度建模与计算,神经元网络动力学的数学性质与方法的研究,生物与物理系统中的非线性与混沌现象,大尺度的视觉神经网络的建模与模拟的研究。
此致
敬礼!
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