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认识你的邻居:突触抑郁症的规范理论

Know Thy Neighbour: A Normative Theory of Synaptic Depression
课程网址: http://videolectures.net/nips09_pfister_ktn/  
主讲教师: Jean-Pascal Pfister
开课单位: 剑桥大学
开课时间: 2010-01-19
课程语种: 英语
中文简介:
突触表现出非凡程度的短期延展性,释放概率和有效突触强度在多个时间尺度上显着变化。从网络中的固定计算操作的角度来看,这似乎是最不可接受的附加噪声程度。我们提出了一种替代理论,根据该理论,短期突触可塑性起着规范性的合理作用。该理论从普通的观察开始,即神经元的尖峰是一个不完整的数字化模拟报告,包含所有关键信息,即其膜电位。我们建议突触的一个关键任务是解决从它接收的峰值和先前预期估计突触前膜电位的逆问题,如在递归滤波器中。我们表明,短期突触抑制具有与最佳估计所需的规范动态非常相似的规范动态,并且它确实支持高质量估计。在此基础上,局部突触后电位和突触资源水平跟踪估计的突触前膜电位的(标度)均值和方差。我们对亚阈值膜电位波动的统计数据和尖峰非线性的形式如何与任何特定细胞类型的短期可塑性特征相关联进行实验可测试预测。
课程简介: Synapses exhibit an extraordinary degree of short-term malleability, with release probabilities and effective synaptic strengths changing markedly over multiple timescales. From the perspective of a fixed computational operation in a network, this seems like a most unacceptable degree of added noise. We suggest an alternative theory according to which short term synaptic plasticity plays a normatively-justifiable role. This theory starts from the commonplace observation that the spiking of a neuron is an incomplete, digital, report of the analog quantity that contains all the critical information, namely its membrane potential. We suggest that one key task for a synapse is to solve the inverse problem of estimating the pre-synaptic membrane potential from the spikes it receives and prior expectations, as in a recursive filter. We show that short-term synaptic depression has canonical dynamics which closely resemble those required for optimal estimation, and that it indeed supports high quality estimation. Under this account, the local postsynaptic potential and the level of synaptic resources track the (scaled) mean and variance of the estimated presynaptic membrane potential. We make experimentally testable predictions for how the statistics of subthreshold membrane potential fluctuations and the form of spiking non-linearity should be related to the properties of short-term plasticity in any particular cell type.
关 键 词: 突触; 替代理论; 神经元
课程来源: 视频讲座网
最后编审: 2019-09-06:lxf
阅读次数: 41