# On Learning Intrinsic Rewards for Policy Gradient Methods

arXiv: https://arxiv.org/abs/1804.06459 · HTML: https://mlsanity.com/paper/1804.06459/

## Key facts

- Cited by 102 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 17 Apr 2018.

## Built on by (most cited first, 30 of 102)

- [Automated Reinforcement Learning (AutoRL): A Survey and Open Problems](https://mlsanity.com/paper/2201.03916/) (2022)
- [Exploration in Deep Reinforcement Learning: From Single-Agent to Multiagent Domain](https://mlsanity.com/paper/2109.06668/) (2021)
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- [Bootstrapped Meta-Learning](https://mlsanity.com/paper/2109.04504/) (2021)
- [Adversarial Intrinsic Motivation for Reinforcement Learning](https://mlsanity.com/paper/2105.13345/) (2021)
- [Comprehensive Overview of Reward Engineering and Shaping in Advancing Reinforcement Learning Applications](https://mlsanity.com/paper/2408.10215/) (2024)
- [Learning Long-Term Reward Redistribution via Randomized Return Decomposition](https://mlsanity.com/paper/2111.13485/) (2021)
- [MEDIRL: Predicting the Visual Attention of Drivers via Maximum Entropy Deep Inverse Reinforcement Learning](https://mlsanity.com/paper/1912.07773/) (2019)
- [Rank the Episodes: A Simple Approach for Exploration in Procedurally-Generated Environments](https://mlsanity.com/paper/2101.08152/) (2021)
- [A Max-Min Entropy Framework for Reinforcement Learning](https://mlsanity.com/paper/2106.10517/) (2021)
- [Discovery of Options via Meta-Learned Subgoals](https://mlsanity.com/paper/2102.06741/) (2021)
- [Generative Adversarial Self-Imitation Learning](https://mlsanity.com/paper/1812.00950/) (2018)
- [Off-Policy Reinforcement Learning with Delayed Rewards](https://mlsanity.com/paper/2106.11854/) (2021)
- [Redeeming Intrinsic Rewards via Constrained Optimization](https://mlsanity.com/paper/2211.07627/) (2022)
- [Continuously Discovering Novel Strategies via Reward-Switching Policy Optimization](https://mlsanity.com/paper/2204.02246/) (2022)
- [Learning How to Propagate Messages in Graph Neural Networks](https://mlsanity.com/paper/2310.00697/) (2023)
- [Stable Gradients for Stable Learning at Scale in Deep Reinforcement Learning](https://mlsanity.com/paper/2506.15544/) (2025)
- [Beyond Sparse Rewards: Enhancing Reinforcement Learning with Language Model Critique in Text Generation](https://mlsanity.com/paper/2401.07382/) (2024)
- [Highly Efficient Self-Adaptive Reward Shaping for Reinforcement Learning](https://mlsanity.com/paper/2408.03029/) (2024)
- [Discovering Diverse Nearly Optimal Policies with Successor Features](https://mlsanity.com/paper/2106.00669/) (2021)
- [Hypernetworks for Zero-shot Transfer in Reinforcement Learning](https://mlsanity.com/paper/2211.15457/) (2022)
- [AutoCost: Evolving Intrinsic Cost for Zero-violation Reinforcement Learning](https://mlsanity.com/paper/2301.10339/) (2023)
- [Behavior Alignment via Reward Function Optimization](https://mlsanity.com/paper/2310.19007/) (2023)
- [In-context Exploration-Exploitation for Reinforcement Learning](https://mlsanity.com/paper/2403.06826/) (2024)
- [SCAR: Shapley Credit Assignment for More Efficient RLHF](https://mlsanity.com/paper/2505.20417/) (2025)
- [Mind the Gap: Offline Policy Optimization for Imperfect Rewards](https://mlsanity.com/paper/2302.01667/) (2023)
- [f-Policy Gradients: A General Framework for Goal Conditioned RL using f-Divergences](https://mlsanity.com/paper/2310.06794/) (2023)
- [Provably Efficient Offline Reinforcement Learning with Trajectory-Wise Reward](https://mlsanity.com/paper/2206.06426/) (2022)
- [LAMARL: LLM-Aided Multi-Agent Reinforcement Learning for Cooperative Policy Generation](https://mlsanity.com/paper/2506.01538/) (2025)
- [A Theoretical Understanding of Gradient Bias in Meta-Reinforcement Learning](https://mlsanity.com/paper/2112.15400/) (2021)

## Abstract (arXiv)

In many sequential decision making tasks, it is challenging to design reward functions that help an RL agent efficiently learn behavior that is considered good by the agent designer. A number of different formulations of the reward-design problem, or close variants thereof, have been proposed in the literature. In this paper we build on the Optimal Rewards Framework of Singh et.al. that defines the optimal intrinsic reward function as one that when used by an RL agent achieves behavior that optimizes the task-specifying or extrinsic reward function. Previous work in this framework has shown how good intrinsic reward functions can be learned for lookahead search based planning agents. Whether it is possible to learn intrinsic reward functions for learning agents remains an open problem. In this paper we derive a novel algorithm for learning intrinsic rewards for policy-gradient based learning agents. We compare the performance of an augmented agent that uses our algorithm to provide additive intrinsic rewards to an A2C-based policy learner (for Atari games) and a PPO-based policy learner (for Mujoco domains) with a baseline agent that uses the same policy learners but with only extrinsic rewards. Our results show improved performance on most but not all of the domains.
