神经科学方面的巨大努力正在努力绘制许多新物种的连接群，包括果蝇果蝇的接近完成。重要的是要问这些模型是否可以使人工智能受益。在这项工作中，我们提出了两个基本问题：（1）生物连接组可以在机器学习中提供的何处以及何时提供使用，（2）哪些设计原理对于提取连接组的良好表示是必要的。为此，我们将秀丽隐杆线虫线虫的运动电路转化为以不同水平的生物物理现实主义水平的人工神经网络，并评估了这些网络在运动和非运动行为任务上训练这些网络的结果。我们证明，生物物理现实主义不必维持使用生物回路的优势。我们还确定，即使没有保留确切的接线图，建筑统计数据也提供了有价值的先验。最后，我们表明，虽然秀丽隐杆线虫运动电路对运动问题提供了强大的感应偏见，但其结构可能会阻碍与运动无关的任务（例如视觉分类问题）。

Artificial neural networks for motor control usually adopt generic architectures like fully connected MLPs. While general, these tabula rasa architectures rely on large amounts of experience to learn, are not easily transferable to new bodies, and have internal dynamics that are difficult to interpret. In nature, animals are born with highly structured connectivity in their nervous systems shaped by evolution; this innate circuitry acts synergistically with learning mechanisms to provide inductive biases that enable most animals to function well soon after birth and learn efficiently. Convolutional networks inspired by visual circuitry have encoded useful biases for vision. However, it is unknown the extent to which ANN architectures inspired by neural circuitry can yield useful biases for other AI domains. In this work, we ask what advantages biologically inspired ANN architecture can provide in the domain of motor control. Specifically, we translate C. elegans locomotion circuits into an ANN model controlling a simulated Swimmer agent. On a locomotion task, our architecture achieves good initial performance and asymptotic performance comparable with MLPs, while dramatically improving data efficiency and requiring orders of magnitude fewer parameters. Our architecture is interpretable and transfers to new body designs. An ablation analysis shows that constrained excitation/inhibition is crucial for learning, while weight initialization contributes to good initial performance. Our work demonstrates several advantages of biologically inspired ANN architecture and encourages future work in more complex embodied control.

突触塑性是神经网络中自我监管无监督学习的强大方法。最近利益的复苏已经在利用人工神经网络（ANNS）以及延期学习的突触可塑性方面开发。已经证明了可塑性来提高这些网络的学习能力在概括到新的环境环境。然而，这些训练有素的网络的长期稳定性尚未被检查。这项工作表明，利用ANN的可塑性导致不稳定于训练期间使用的预先指定的寿命。这种不稳定可以导致奖励寻求行为的戏剧性下降，或者快速导致到达环境终端状态。在许多训练时间范围内的两个不同环境中，这种行为被认为是在许多不同环境中的几种可塑性规则保持一致：推车极衡问题和四足球运动问题。我们通过使用尖刺神经元来提出这种不稳定性的解决方案。

尖峰神经网络（SNN）引起了脑启发的人工智能和计算神经科学的广泛关注。它们可用于在多个尺度上模拟大脑中的生物信息处理。更重要的是，SNN是适当的抽象水平，可以将大脑和认知的灵感带入人工智能。在本文中，我们介绍了脑启发的认知智力引擎（Braincog），用于创建脑启发的AI和脑模拟模型。 Braincog将不同类型的尖峰神经元模型，学习规则，大脑区域等作为平台提供的重要模块。基于这些易于使用的模块，BrainCog支持各种受脑启发的认知功能，包括感知和学习，决策，知识表示和推理，运动控制和社会认知。这些受脑启发的AI模型已在各种受监督，无监督和强化学习任务上有效验证，并且可以用来使AI模型具有多种受脑启发的认知功能。为了进行大脑模拟，Braincog实现了决策，工作记忆，神经回路的结构模拟以及小鼠大脑，猕猴大脑和人脑的整个大脑结构模拟的功能模拟。一个名为BORN的AI引擎是基于Braincog开发的，它演示了如何将Braincog的组件集成并用于构建AI模型和应用。为了使科学追求解码生物智能的性质并创建AI，Braincog旨在提供必要且易于使用的构件，并提供基础设施支持，以开发基于脑部的尖峰神经网络AI，并模拟认知大脑在多个尺度上。可以在https://github.com/braincog-x上找到Braincog的在线存储库。

This chapter sheds light on the synaptic organization of the brain from the perspective of computational neuroscience. It provides an introductory overview on how to account for empirical data in mathematical models, implement them in software, and perform simulations reflecting experiments. This path is demonstrated with respect to four key aspects of synaptic signaling: the connectivity of brain networks, synaptic transmission, synaptic plasticity, and the heterogeneity across synapses. Each step and aspect of the modeling and simulation workflow comes with its own challenges and pitfalls, which are highlighted and addressed in detail.

Understanding how biological neural networks carry out learning using spike-based local plasticity mechanisms can lead to the development of powerful, energy-efficient, and adaptive neuromorphic processing systems. A large number of spike-based learning models have recently been proposed following different approaches. However, it is difficult to assess if and how they could be mapped onto neuromorphic hardware, and to compare their features and ease of implementation. To this end, in this survey, we provide a comprehensive overview of representative brain-inspired synaptic plasticity models and mixed-signal CMOS neuromorphic circuits within a unified framework. We review historical, bottom-up, and top-down approaches to modeling synaptic plasticity, and we identify computational primitives that can support low-latency and low-power hardware implementations of spike-based learning rules. We provide a common definition of a locality principle based on pre- and post-synaptic neuron information, which we propose as a fundamental requirement for physical implementations of synaptic plasticity. Based on this principle, we compare the properties of these models within the same framework, and describe the mixed-signal electronic circuits that implement their computing primitives, pointing out how these building blocks enable efficient on-chip and online learning in neuromorphic processing systems.

The term ``neuromorphic'' refers to systems that are closely resembling the architecture and/or the dynamics of biological neural networks. Typical examples are novel computer chips designed to mimic the architecture of a biological brain, or sensors that get inspiration from, e.g., the visual or olfactory systems in insects and mammals to acquire information about the environment. This approach is not without ambition as it promises to enable engineered devices able to reproduce the level of performance observed in biological organisms -- the main immediate advantage being the efficient use of scarce resources, which translates into low power requirements. The emphasis on low power and energy efficiency of neuromorphic devices is a perfect match for space applications. Spacecraft -- especially miniaturized ones -- have strict energy constraints as they need to operate in an environment which is scarce with resources and extremely hostile. In this work we present an overview of early attempts made to study a neuromorphic approach in a space context at the European Space Agency's (ESA) Advanced Concepts Team (ACT).

尖峰神经网络（SNN）提供了一个新的计算范式，能够高度平行，实时处理。光子设备是设计与SNN计算范式相匹配的高带宽，平行体系结构的理想选择。 CMO和光子元件的协整允许将低损耗的光子设备与模拟电子设备结合使用，以更大的非线性计算元件的灵活性。因此，我们在整体硅光子学（SIPH）过程上设计和模拟了光电尖峰神经元电路，该过程复制了超出泄漏的集成和火（LIF）之外有用的尖峰行为。此外，我们探索了两种学习算法，具有使用Mach-Zehnder干涉法（MZI）网格作为突触互连的片上学习的潜力。实验证明了随机反向传播（RPB）的变体，并在简单分类任务上与标准线性回归的性能相匹配。同时，将对比性HEBBIAN学习（CHL）规则应用于由MZI网格组成的模拟神经网络，以进行随机输入输出映射任务。受CHL训练的MZI网络的性能比随机猜测更好，但不符合理想神经网络的性能（没有MZI网格施加的约束）。通过这些努力，我们证明了协调的CMO和SIPH技术非常适合可扩展的SNN计算体系结构的设计。

In the brain, information is encoded, transmitted and used to inform behaviour at the level of timing of action potentials distributed over population of neurons. To implement neural-like systems in silico, to emulate neural function, and to interface successfully with the brain, neuromorphic circuits need to encode information in a way compatible to that used by populations of neuron in the brain. To facilitate the cross-talk between neuromorphic engineering and neuroscience, in this Review we first critically examine and summarize emerging recent findings about how population of neurons encode and transmit information. We examine the effects on encoding and readout of information for different features of neural population activity, namely the sparseness of neural representations, the heterogeneity of neural properties, the correlations among neurons, and the time scales (from short to long) at which neurons encode information and maintain it consistently over time. Finally, we critically elaborate on how these facts constrain the design of information coding in neuromorphic circuits. We focus primarily on the implications for designing neuromorphic circuits that communicate with the brain, as in this case it is essential that artificial and biological neurons use compatible neural codes. However, we also discuss implications for the design of neuromorphic systems for implementation or emulation of neural computation.

近年来，尖峰神经网络（SNN）由于其丰富的时空动力学，各种编码方法和事件驱动的特征而自然拟合神经形态硬件，因此在脑启发的智能上受到了广泛的关注。随着SNN的发展，受到脑科学成就启发和针对人工通用智能的新兴研究领域的脑力智能变得越来越热。本文回顾了最新进展，并讨论了来自五个主要研究主题的SNN的新领域，包括基本要素（即尖峰神经元模型，编码方法和拓扑结构），神经形态数据集，优化算法，软件，软件和硬件框架。我们希望我们的调查能够帮助研究人员更好地了解SNN，并激发新作品以推进这一领域。

We propose that in order to harness our understanding of neuroscience toward machine learning, we must first have powerful tools for training brain-like models of learning. Although substantial progress has been made toward understanding the dynamics of learning in the brain, neuroscience-derived models of learning have yet to demonstrate the same performance capabilities as methods in deep learning such as gradient descent. Inspired by the successes of machine learning using gradient descent, we demonstrate that models of neuromodulated synaptic plasticity from neuroscience can be trained in Spiking Neural Networks (SNNs) with a framework of learning to learn through gradient descent to address challenging online learning problems. This framework opens a new path toward developing neuroscience inspired online learning algorithms.

预测性编码提供了对皮质功能的潜在统一说明 - 假设大脑的核心功能是最小化有关世界生成模型的预测错误。该理论与贝叶斯大脑框架密切相关，在过去的二十年中，在理论和认知神经科学领域都产生了重大影响。基于经验测试的预测编码的改进和扩展的理论和数学模型，以及评估其在大脑中实施的潜在生物学合理性以及该理论所做的具体神经生理学和心理学预测。尽管存在这种持久的知名度，但仍未对预测编码理论，尤其是该领域的最新发展进行全面回顾。在这里，我们提供了核心数学结构和预测编码的逻辑的全面综述，从而补充了文献中最新的教程。我们还回顾了该框架中的各种经典和最新工作，从可以实施预测性编码的神经生物学现实的微电路到预测性编码和广泛使用的错误算法的重新传播之间的紧密关系，以及对近距离的调查。预测性编码和现代机器学习技术之间的关系。

短期可塑性（STP）是一种将腐烂记忆存储在大脑皮质突触中的机制。在计算实践中，已经使用了STP，但主要是在尖峰神经元的细分市场中，尽管理论预测它是对某些动态任务的最佳解决方案。在这里，我们提出了一种新型的经常性神经单元，即STP神经元（STPN），它确实实现了惊人的功能。它的关键机制是，突触具有一个状态，通过与偶然性的自我连接在时间上传播。该公式使能够通过时间返回传播来训练可塑性，从而导致一种学习在短期内学习和忘记的形式。 STPN的表现优于所有测试的替代方案，即RNN，LSTMS，其他具有快速重量和可区分可塑性的型号。我们在监督和强化学习（RL）以及协会​​检索，迷宫探索，Atari视频游戏和Mujoco Robotics等任务中证实了这一点。此外，我们计算出，在神经形态或生物电路中，STPN最大程度地减少了模型的能量消耗，因为它会动态降低个体突触。基于这些，生物学STP可能是一种强大的进化吸引子，可最大程度地提高效率和计算能力。现在，STPN将这些神经形态的优势带入了广泛的机器学习实践。代码可从https://github.com/neuromorphiccomputing/stpn获得

Artificial Intelligence (AI) and Machine Learning (ML) are weaving their way into the fabric of society, where they are playing a crucial role in numerous facets of our lives. As we witness the increased deployment of AI and ML in various types of devices, we benefit from their use into energy-efficient algorithms for low powered devices. In this paper, we investigate a scale and medium that is far smaller than conventional devices as we move towards molecular systems that can be utilized to perform machine learning functions, i.e., Molecular Machine Learning (MML). Fundamental to the operation of MML is the transport, processing, and interpretation of information propagated by molecules through chemical reactions. We begin by reviewing the current approaches that have been developed for MML, before we move towards potential new directions that rely on gene regulatory networks inside biological organisms as well as their population interactions to create neural networks. We then investigate mechanisms for training machine learning structures in biological cells based on calcium signaling and demonstrate their application to build an Analog to Digital Converter (ADC). Lastly, we look at potential future directions as well as challenges that this area could solve.

在过去十年中，我们目睹了深度学习的兴起，以占据人工智能领域。人工神经网络的进步与具有大的内存容量大的硬件加速器的相应进步，以及大型数据集的可用性，使能研究人员和从业者能够培训和部署复杂的神经网络模型，这些模型在几个方面实现了最先进的性能跨越计算机视觉，自然语言处理和加强学习的领域。然而，由于这些神经网络变得更大，更复杂，更广泛地使用，目前深度学习模型的基本问题变得更加明显。已知最先进的深度学习模型遭受稳健性不良，无法适应新的任务设置的问题，以要求刚性和不灵活的配置假设。来自集体智能的想法，特别是来自复杂系统，如自组织，紧急行为，群优化和蜂窝系统的复杂系统的概念倾向于产生鲁棒，适应性，并且对环境配置具有较小的刚性假设的解决方案。因此，很自然地看到这些想法纳入更新的深度学习方法。在这篇综述中，我们将提供神经网络研究的历史背景，即神经网络研究的复杂系统的参与，并突出了现代深度学习研究中的几个活跃区域，这些研究融合了集体智能的原则，以推进其当前能力。为了促进双向思想流动，我们还讨论了利用现代深度学习模型的工作，以帮助推进复杂的系统研究。我们希望这次审查可以作为复杂系统和深度学习社区之间的桥梁，以促进思想的交叉授粉和促进跨学科的新合作。

受生物神经元的启发，激活功能在许多现实世界中常用的任何人工神经网络的学习过程中起着重要作用。文献中已经提出了各种激活功能，用于分类和回归任务。在这项工作中，我们调查了过去已经使用的激活功能以及当前的最新功能。特别是，我们介绍了多年来激活功能的各种发展以及这些激活功能的优势以及缺点或局限性。我们还讨论了经典（固定）激活功能，包括整流器单元和自适应激活功能。除了基于表征的激活函数的分类法外，还提出了基于应用的激活函数的分类法。为此，对MNIST，CIFAR-10和CIFAR-100等分类数据集进行了各种固定和自适应激活函数的系统比较。近年来，已经出现了一个具有物理信息的机器学习框架，以解决与科学计算有关的问题。为此，我们还讨论了在物理知识的机器学习框架中使用的激活功能的各种要求。此外，使用Tensorflow，Pytorch和Jax等各种机器学习库之间进行了不同的固定和自适应激活函数进行各种比较。

本文提出了一种新的方法，称为模块化语法进化（MGE），以验证以下假设，即限制了神经进化的解决方案空间到模块化和简单的神经网络，可以有效地生成较小，更结构化的神经网络，同时提供可接受的（在某些方面）案例优于大型数据集的精度。 MGE还在两个方向上增强了最新的语法演化（GE）方法。首先，MGE的表示是模块化的，因为每个个体都有一组基因，并且每个基因都通过语法规则映射到神经元。其次，所提出的表示形式减轻了GE的两个重要缺点，即表示较低的表示性和弱位置，以生成具有大量神经元的模块化和多层网络。我们使用MGE定义和评估具有和不具有模块化的五种不同形式的结构，并找到没有耦合更有效的单层模块。我们的实验表明，模块化有助于更快地找到更好的神经网络。我们使用了十个具有不同尺寸，功能计数和输出类计数的众所周知的分类基准验证了提出的方法。我们的实验结果表明，MGE相对于现有的神经进化方法提供了卓越的准确性，并且返回分类器比其他机器学习生成的分类器要简单得多。最后，我们从经验上证明，MGE在局部性和可伸缩性属性方面优于其他GE方法。

人工神经网络从其生物学对应物中汲取了很多灵感，成为我们最好的机器感知系统。这项工作总结了一些历史，并将现代理论神经科学纳入了深度学习领域的人工神经网络的实验。具体而言，迭代幅度修剪用于训练稀疏连接的网络，重量减少33倍而不会损失性能。这些用于测试并最终拒绝这样的假设：仅体重稀疏就可以改善图像噪声稳健性。最近的工作减轻了使用重量稀疏性，激活稀疏性和主动树突建模的灾难性遗忘。本文复制了这些发现，并扩展了培训卷积神经网络的方法，以更具挑战性的持续学习任务。该代码已公开可用。

Humans and animals have the ability to continually acquire, fine-tune, and transfer knowledge and skills throughout their lifespan. This ability, referred to as lifelong learning, is mediated by a rich set of neurocognitive mechanisms that together contribute to the development and specialization of our sensorimotor skills as well as to long-term memory consolidation and retrieval. Consequently, lifelong learning capabilities are crucial for computational systems and autonomous agents interacting in the real world and processing continuous streams of information. However, lifelong learning remains a long-standing challenge for machine learning and neural network models since the continual acquisition of incrementally available information from non-stationary data distributions generally leads to catastrophic forgetting or interference. This limitation represents a major drawback for state-of-the-art deep neural network models that typically learn representations from stationary batches of training data, thus without accounting for situations in which information becomes incrementally available over time. In this review, we critically summarize the main challenges linked to lifelong learning for artificial learning systems and compare existing neural network approaches that alleviate, to different extents, catastrophic forgetting. Although significant advances have been made in domain-specific learning with neural networks, extensive research efforts are required for the development of robust lifelong learning on autonomous agents and robots. We discuss well-established and emerging research motivated by lifelong learning factors in biological systems such as structural plasticity, memory replay, curriculum and transfer learning, intrinsic motivation, and multisensory integration.

为了在专门的神经形态硬件中进行节能计算，我们提出了尖峰神经编码，这是基于预测性编码理论的人工神经模型家族的实例化。该模型是同类模型，它是通过在“猜测和检查”的永无止境过程中运行的，神经元可以预测彼此的活动值，然后调整自己的活动以做出更好的未来预测。我们系统的互动性，迭代性质非常适合感官流预测的连续时间表述，并且如我们所示，模型的结构产生了局部突触更新规则，可以用来补充或作为在线峰值定位的替代方案依赖的可塑性。在本文中，我们对模型的实例化进行了实例化，该模型包括泄漏的集成和火灾单元。但是，我们系统所在的框架自然可以结合更复杂的神经元，例如Hodgkin-Huxley模型。我们在模式识别方面的实验结果证明了当二进制尖峰列车是通信间通信的主要范式时，模型的潜力。值得注意的是，尖峰神经编码在分类绩效方面具有竞争力，并且在从任务序列中学习时会降低遗忘，从而提供了更经济的，具有生物学上的替代品，可用于流行的人工神经网络。