Gradient-Free Continual Learning

Grzegorz Rypeść

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arXiv · 2504.01219

Gradient-Free Continual Learning

Grzegorz Rypeść

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Abstract

Neural networks are notorious for forgetting old skills when taught new ones - a problem known as catastrophic forgetting. Standard continual learning techniques try to fix this by saving old data or relying on complex gradient updates, but these methods fail when past data cannot be stored due to memory or privacy constraints. To solve this, we propose EvoCL, a gradient-free approach that uses evolutionary algorithms to update the network without needing old data or gradients. EvoCL uses a lightweight adapter module to translate saved representations from past tasks into the model's current space, allowing it to learn new tasks while keeping past knowledge intact. Across multiple benchmarks, EvoCL matches or exceeds standard performance under strict memory constraints, offering a simple and flexible new direction for continual learning. The code to reproduce these results is available at https://github.com/grypesc/EvoCL.

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Grzegorz Rypeść. 2025-04-01. Gradient-Free Continual Learning. https://arxiv.org/abs/2504.01219

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