论文标题
通过解释机器学习模型来了解人脑中的信息处理
Understanding Information Processing in Human Brain by Interpreting Machine Learning Models
论文作者
论文摘要
论文探讨了机器学习方法在创建神经处理的直观计算模型中所起的作用。结合可解释性技术,机器学习可以取代人类建模者,并将人类努力的重点转移到从现成的模型中提取知识,并将这些知识阐明为真实的直观描述。这种观点使案例倾向于更大的作用,即探索性和数据驱动的计算神经科学方法可以在与传统假设驱动的方法并存时发挥作用。 在知识表示分类法的背景下,我们通过三个研究项目来体现所提出的方法,这些研究项目在三种不同级别的神经组织的机器学习方法上采用可解释性技术。第一项研究(第3章)探讨了对100名人类受试者的脑记录进行训练的随机森林解码器的重要性分析,以识别在视觉分类任务中表征局部神经活动的光谱符号特征。第二项研究(第4章)采用表示相似性分析,以比较沿腹流区域的神经反应与深卷积神经网络层的激活。第三项研究(第5章)提出了一种允许测试对象实时探索其神经信号的状态表示的方法。这是通过使用拓扑维度降低技术来实现的,该技术可将神经数据从计算机使用的多维表示转换为人类可以掌握的二维表示。 方法,分类法和示例为机器学习方法在神经科学中自动发现的适用性提供了有力的案例。
The thesis explores the role machine learning methods play in creating intuitive computational models of neural processing. Combined with interpretability techniques, machine learning could replace human modeler and shift the focus of human effort to extracting the knowledge from the ready-made models and articulating that knowledge into intuitive descroptions of reality. This perspective makes the case in favor of the larger role that exploratory and data-driven approach to computational neuroscience could play while coexisting alongside the traditional hypothesis-driven approach. We exemplify the proposed approach in the context of the knowledge representation taxonomy with three research projects that employ interpretability techniques on top of machine learning methods at three different levels of neural organization. The first study (Chapter 3) explores feature importance analysis of a random forest decoder trained on intracerebral recordings from 100 human subjects to identify spectrotemporal signatures that characterize local neural activity during the task of visual categorization. The second study (Chapter 4) employs representation similarity analysis to compare the neural responses of the areas along the ventral stream with the activations of the layers of a deep convolutional neural network. The third study (Chapter 5) proposes a method that allows test subjects to visually explore the state representation of their neural signal in real time. This is achieved by using a topology-preserving dimensionality reduction technique that allows to transform the neural data from the multidimensional representation used by the computer into a two-dimensional representation a human can grasp. The approach, the taxonomy, and the examples, present a strong case for the applicability of machine learning methods to automatic knowledge discovery in neuroscience.