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高斯过程神经响应函数的主动学习

Active learning of neural response functions with Gaussian processes
课程网址: http://videolectures.net/nips2011_park_neuralresponse/  
主讲教师: Mijung Park
开课单位: 德克萨斯大学
开课时间: 2012-09-06
课程语种: 英语
中文简介:
大量的文献集中在估计一个捕捉神经元刺激敏感性的低维特征空间的问题上。然而,从特征空间到神经元输出尖峰率的非线性函数估计问题的研究相对较少。在这里,我们使用非线性函数无穷维空间上的高斯过程(GP)先验来获得线性非线性Poisson(LNP)编码模型中“非线性”的贝叶斯估计。与传统方法(如参数形式、直方图、三次样条曲线)相比,这提供了灵活性、鲁棒性和计算可处理性。最重要的是,我们开发了一个基于不确定性抽样的优化实验设计框架。这涉及到自适应地选择刺激以尽可能少的实验数据来描述非线性,并且依赖于一种使用拉普拉斯近似快速更新超参数的方法。我们将这些方法应用于猕猴V1中颜色调谐神经元的数据。我们估计的非线性在三维空间的圆锥对比,这表明V1组合圆锥输入高度非线性的方式。通过仿真实验,我们发现优化设计大大减少了估计这种非线性组合规则所需的数据量。
课程简介: A sizable literature has focused on the problem of estimating a low-dimensional feature space capturing a neuron's stimulus sensitivity. However, comparatively little work has addressed the problem of estimating the nonlinear function from feature space to a neuron's output spike rate. Here, we use a Gaussian process (GP) prior over the infinite-dimensional space of nonlinear functions to obtain Bayesian estimates of the ""nonlinearity"" in the linear-nonlinear-Poisson (LNP) encoding model. This offers flexibility, robustness, and computational tractability compared to traditional methods (e.g., parametric forms, histograms, cubic splines). Most importantly, we develop a framework for optimal experimental design based on uncertainty sampling. This involves adaptively selecting stimuli to characterize the nonlinearity with as little experimental data as possible, and relies on a method for rapidly updating hyperparameters using the Laplace approximation. We apply these methods to data from color-tuned neurons in macaque V1. We estimate nonlinearities in the 3D space of cone contrasts, which reveal that V1 combines cone inputs in a highly nonlinear manner. With simulated experiments, we show that optimal design substantially reduces the amount of data required to estimate this nonlinear combination rule.
关 键 词: 神经元刺激敏感性; 非线性贝叶斯估计; 高斯
课程来源: 视频讲座网
数据采集: 2020-12-14:yxd
最后编审: 2020-12-15:cjy
阅读次数: 30