论文标题
调整卷积尖峰神经网络,具有生物学上的奖励传播
Tuning Convolutional Spiking Neural Network with Biologically-plausible Reward Propagation
论文作者
论文摘要
与标准人工神经网络(ANN)相比,尖峰神经网络(SNN)包含更具生物学现实的结构和生物启发的学习原理。 SNN被认为是第三代ANN,具有较低的计算成本的强大计算功能。 SNN中的神经元是非差异性的,包含腐烂的历史状态,并在其状态达到点火阈值后产生基于事件的尖峰。 SNN的这些动态特征使得很难通过标准返回(BP)进行直接训练,这在生物学上也不是可行的。在本文中,提出了一种具有生物学成分的奖励繁殖(BRP)算法,并将其应用于SNN体系结构,并具有尖峰连接(具有1D和2D卷积内核)和完整连接层。与标准BP逐层传播从邮政为突触前神经元的误差信号的标准BP不同,BRP传播目标标签,而不是直接从输出层到所有前隐藏层的误差。这项工作与新皮层皮质柱中自上而下的奖励引导学习更加一致。仅具有局部梯度差异的突触修饰是用伪BP诱导的,这也可能被峰值依赖性可塑性(STDP)所取代。在空间(包括MNIST和CIFAR-10)和时间(包括tidigits和dvSgesture)任务上进一步验证了所提出的BRP-SNN的性能,与其他基于BP的SNN相比,使用BRP的SNN具有相似的精度,与其他基于BP的SNN相比,SNN具有相似的精度,并且比ANN节省了50%的计算成本。我们认为,生物学上合理的学习规则引入了生物学上现实的SNN的培训程序,将为我们提供更多的提示和灵感,以更好地理解生物体系的智能性质。
Spiking Neural Networks (SNNs) contain more biologically realistic structures and biologically-inspired learning principles than those in standard Artificial Neural Networks (ANNs). SNNs are considered the third generation of ANNs, powerful on the robust computation with a low computational cost. The neurons in SNNs are non-differential, containing decayed historical states and generating event-based spikes after their states reaching the firing threshold. These dynamic characteristics of SNNs make it difficult to be directly trained with the standard backpropagation (BP), which is also considered not biologically plausible. In this paper, a Biologically-plausible Reward Propagation (BRP) algorithm is proposed and applied to the SNN architecture with both spiking-convolution (with both 1D and 2D convolutional kernels) and full-connection layers. Unlike the standard BP that propagates error signals from post to presynaptic neurons layer by layer, the BRP propagates target labels instead of errors directly from the output layer to all pre-hidden layers. This effort is more consistent with the top-down reward-guiding learning in cortical columns of the neocortex. Synaptic modifications with only local gradient differences are induced with pseudo-BP that might also be replaced with the Spike-Timing Dependent Plasticity (STDP). The performance of the proposed BRP-SNN is further verified on the spatial (including MNIST and Cifar-10) and temporal (including TIDigits and DvsGesture) tasks, where the SNN using BRP has reached a similar accuracy compared to other state-of-the-art BP-based SNNs and saved 50% more computational cost than ANNs. We think the introduction of biologically plausible learning rules to the training procedure of biologically realistic SNNs will give us more hints and inspirations toward a better understanding of the biological system's intelligent nature.