在动态突触皮质神经网络信息处理Information processing in cortical neural networks with dynamic synaptic connections |
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课程网址: | http://videolectures.net/eccs08_tsodyks_ipicnn/ |
主讲教师: | Misha Tsodyks |
开课单位: | 魏茨曼科学研究所 |
开课时间: | 2008-10-17 |
课程语种: | 英语 |
中文简介: | 皮质中的突触传递的特征在于活动依赖性短期可塑性(STP),其可大致分类为突触抑制和突触促进。如最近的实验所示,不同的皮质区域表现出促进和抑制的可变混合,这也是不同类型神经元之间的连接的特异性。在我的演讲的前半部分,我将描述动态突触传递的基础知识,其生物物理基础以及在生物物理动机的现象学模型中捕获的方式。我还将讨论STP对新皮层神经元集合之间信息传递的一些直接影响。在演示的后半部分,我将重点介绍STP对复发网络动态和结果神经计算的影响。我将介绍“人口峰值”(PSs),这是一种高度随机化活动的短暂时期,这种活动出现在复发网络中,在兴奋性神经元之间存在主导的突触抑制。 PS可以构成听觉皮层神经元的一些反应特性的基础。然后,我将描述最近引入的观点,即可以利用突触促进来维持目标神经元之间反复连接的促进水平中的进入刺激的信息,从而为短期记忆提供有效的机制,持续几周。刺激终止后几秒钟。 |
课程简介: | Synaptic transmission in the cortex is characterized by the activity-dependent short-term plasticity (STP), which can be broadly classified as synaptic depression and synaptic facilitation. As recent experiments indicate, different cortical areas exhibit variable mixes of facilitation and depression, which are also specific for connections between different types of neurons. In the first half of my presentation, I will describe the basics of dynamic synaptic transmission, its biophysical underpinnings and the ways it can be captured in biophysically motivated phenomenological models. I will also discuss some immediate implications of STP on information transmission between ensembles of neocortical neurons. In the second half of the presentation, I will focus on the effects of STP on the dynamics of recurrent networks and resulting neural computation. I will introduce the 'population spikes' (PSs), which are brief epochs of highly ynchronized activity that emerge in recurrent networks with dominating synaptic depression between excitatory neurons. PSs can underlie some of the response properties of neurons in the auditory cortex. I will then describe the recently introduced idea that synaptic facilitation could be utilized in order to maintain information about the incoming stimuli in the facilitation level of recurrent connections between the targeted neurons, thus providing an effective mechanism for short-term memory for a period of several seconds after the termination of the stimulus. |
关 键 词: | 突触传递; 突触抑制; 突触易化; 神经元 |
课程来源: | 视频讲座网 |
最后编审: | 2020-06-06:liush |
阅读次数: | 57 |