Training

Catastrophic Forgetting

Quick Answer

When training on new data severely degrades performance on previously learned tasks.

Catastrophic forgetting occurs when fine-tuning a model on new data causes performance degradation on old tasks. The model's weights shift to optimize new data at the expense of previous knowledge. This is a major challenge in continual learning and fine-tuning. Mitigations include: regularization (keep weights close to original), replay (include old data), and architectural approaches. Understanding forgetting is crucial for multi-task learning. High-quality fine-tuning attempts to minimize forgetting.

Last verified: 2026-04-08

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