catastrophic forgetting prevention
**Catastrophic Forgetting Prevention** encompasses **techniques that prevent a neural network from losing previously learned knowledge when trained on new tasks** — a critical challenge in continual learning, transfer learning, and fine-tuning scenarios.
**Key Prevention Techniques**
- **Regularization-Based**:
- **EWC** (Elastic Weight Consolidation): Penalize changes to weights important for previous tasks.
- **L2-SP**: Regularize toward the pre-trained weights.
- **Architecture-Based**:
- **Progressive Networks**: Add new columns for new tasks, freeze old columns.
- **PackNet**: Prune and freeze subnetworks for each task.
- **Replay-Based**:
- **Experience Replay**: Store and replay examples from previous tasks.
- **Generative Replay**: Use a generative model to synthesize past data.
**Why It Matters**
- **Continual Learning**: The #1 obstacle to lifelong learning in neural networks.
- **Fine-Tuning**: Aggressive fine-tuning on small datasets can destroy pre-trained knowledge.
- **Practical**: Any system deployed over time (recommendation engines, autonomous vehicles) faces catastrophic forgetting.
**Catastrophic Forgetting Prevention** is **the art of learning new tricks without forgetting old ones** — the central challenge in making neural networks truly adaptable over time.