arXiv Machine Learning

Towards Understanding the Impact of Plasticity Loss on Reinforcement Learning in Stochastic Environments

The paper investigates how plasticity loss affects deep reinforcement learning in stochastic environments. By training SAC agents on DeepMind Control tasks with varying observation and action noise, the authors find that plasticity-preserving techniques improve robustness, especially as noise increases, while resets combined with layer normalization perform worse. They also observe that stochasticity can accelerate plasticity loss in harder tasks, but in easier settings noise can act as a regularizer, and that plasticity loss is most pronounced early in training, with TD instability dominating in the most challenging scenarios.

arXiv Machine Learning
Jun 25

Stagnant Neuron: Towards Understanding the Plasticity Loss in Multi-Agent Reinforcement Learning Value Factorization Methods

arXiv:2606. 25335v1 Announce Type: new Abstract: Multi-Agent Reinforcement Learning (MARL) value factorization methods can suffer from a loss of plasticity, gradually failing to adapt when transferring to new task instances.

By Zhengzhu Liu, Zeming Gao, Haoyuan Qin, Jiawei Hu, Junhao Wu, Miao Zhu, Haipeng Zhang, Chennan Ma, Siqi Shen, Cheng Wang
Hugging Face Trending Papers
Jun 24

Stagnant Neuron: Towards Understanding the Plasticity Loss in Multi-Agent Reinforcement Learning Value Factorization Methods

Multi-Agent Reinforcement Learning (MARL) value factorization methods can suffer from a loss of plasticity, gradually failing to adapt when transferring to new task instances. We trace this issue to stagnant neurons, units whose gradient updates become negligibly small relative to their weights, thereby hindering learning.

arXiv AI
Jun 6

Retry Policy Gradients in Continuous Action Spaces

arXiv:2606. 05888v1 Announce Type: new Abstract: Retry-based objectives such as pass@K and max@K optimize the best return obtained from multiple sampled trajectories, and recent work has shown that they can promote exploration without explicit exploration bonuses.

By Soichiro Nishimori, Paavo Parmas
arXiv Machine Learning
Aug 20

SingularClip: Preventing Spectral Collapse to Maintain Plasticity in Continual and Reinforcement Learning

The paper introduces SingularClip, a method that periodically clips the singular values of all weight matrices to prevent spectral collapse, a newly identified cause of plasticity loss in neural networks trained on nonstationary tasks. The authors empirically and theoretically analyze how growing anisotropy of singular values degrades the ability to fit new targets, and demonstrate that SingularClip outperforms baseline approaches in both continual supervised learning and deep reinforcement learning settings.

By Tyler Kastner, Nimrod De La Vega, Amir-massoud Farahmand
arXiv Machine Learning
Jun 11

Space-sampled Value Decay: Forgetting Mechanisms for Non-stationary Deep Reinforcement Learning

arXiv:2606. 11797v1 Announce Type: new Abstract: Studies on rodents such as mice have shown the capabilities to adapt their behavior when dealing with changing parameters (``drift'') of the environment even if no information about change is provided (uncertainty) -- a behavior that can be modeled by forgetting mechanisms.

By Felix St\"orck, Fabian Hinder, Barbara Hammer
arXiv AI
Aug 19

Integrating Novelty and Surprise for Experience Prioritization and Exploration in Image-Based Reinforcement Learning

The paper proposes Novelty and Surprise Prioritized Experience Replay (NSPER) for image-based reinforcement learning, combining novelty to highlight underrepresented states and surprise to reveal gaps in the agent’s knowledge. An extended version, NSPER+R, also uses these signals as intrinsic rewards to enhance both replay quality and exploration. Experiments on DeepMind Control Suite tasks demonstrate that NSPER and NSPER+R accelerate training and improve convergence compared to existing methods.

By Hoda Yamani, Henry Williams, Bruce A. MacDonald