Anatomy of Catastrophic Forgetting: Hidden Representations and Task Semantics
Not on the map. Why?
Abstract (arXiv)
A central challenge in developing versatile machine learning systems is catastrophic forgetting: a model trained on tasks in sequence will suffer significant performance drops on earlier tasks. Despite the ubiquity of catastrophic forgetting, there is limited understanding of the underlying process and its causes. In this paper, we address this important knowledge gap, investigating how forgetting affects representations in neural network models. Through representational analysis techniques, we find that deeper layers are disproportionately the source of forgetting. Supporting this, a study of methods to mitigate forgetting illustrates that they act to stabilize deeper layers. These insights enable the development of an analytic argument and empirical picture relating the degree of forgetting to representational similarity between tasks. Consistent with this picture, we observe maximal forgetting occurs for task sequences with intermediate similarity. We perform empirical studies on the standard split CIFAR-10 setup and also introduce a novel CIFAR-100 based task approximating realistic input distribution shift.
Key facts. Cited by 158 papers in the map (data through 7 Oct 2026). First posted on arXiv 14 Jul 2020.
Builds on
No reference list yet.
Built on by
Citing papers per year: 2021: 17; 2022: 27; 2023: 31; 2024: 39; 2025: 19; 2026: 25.
158 papers.
Sort:
By area:
- 2021A General Language Assistant as a Laboratory for Alignmentcited by 1,023
- 2023A Comprehensive Survey of Continual Learning: Theory, Method and Applicationcited by 860
- 2022Surgical Fine-Tuning Improves Adaptation to Distribution Shiftscited by 205
- 2021An Empirical Investigation of the Role of Pre-training in Lifelong Learningcited by 134
- 2021Achieving Forgetting Prevention and Knowledge Transfer in Continual Learningcited by 91
- 2021Continual Learning in the Teacher-Student Setup: Impact of Task Similaritycited by 86
- 2024How Do Large Language Models Acquire Factual Knowledge During Pretraining?cited by 86
- 2022Reliability of CKA as a Similarity Measure in Deep Learningcited by 82
- 2022How catastrophic can catastrophic forgetting be in linear regression?cited by 80
- 2022Probing Representation Forgetting in Supervised and Unsupervised Continual Learningcited by 74
- 2022Teaching Structured Vision&Language Concepts to Vision&Language Modelscited by 71
- 2023Theory on Forgetting and Generalization of Continual Learningcited by 69
38 more
- 2022Continual Learning with Foundation Models: An Empirical Study of Latent Replaycited by 61
- 2022A Closer Look at Rehearsal-Free Continual Learningcited by 54
- 2023Achieving a Better Stability-Plasticity Trade-off via Auxiliary Networks in Continual Learningcited by 41
- 2022Continual Normalization: Rethinking Batch Normalization for Online Continual Learningcited by 40
- 2021Self-Supervised Pre-Training for Transformer-Based Person Re-Identificationcited by 36
- 2023The Tunnel Effect: Building Data Representations in Deep Neural Networkscited by 34
- 2022The Effect of Task Ordering in Continual Learningcited by 30
- 2022Analysis of Catastrophic Forgetting for Random Orthogonal Transformation Tasks in the Overparameterized Regimecited by 28
- 2021Kernel Continual Learningcited by 27
- 2022How to Reuse and Compose Knowledge for a Lifetime of Tasks: A Survey on Continual Learning and Functional Compositioncited by 27
- 2023Degeneration-Tuning: Using Scrambled Grid shield Unwanted Concepts from Stable Diffusioncited by 27
- 2024The Joint Effect of Task Similarity and Overparameterization on Catastrophic Forgetting -- An Analytical Modelcited by 26
- 2024CLAP4CLIP: Continual Learning with Probabilistic Finetuning for Vision-Language Modelscited by 25
- 2024Fine-tuning Reinforcement Learning Models is Secretly a Forgetting Mitigation Problemcited by 23
- 2023A Survey on Continual Semantic Segmentation: Theory, Challenge, Method and Applicationcited by 21
- 2022Challenging Common Assumptions about Catastrophic Forgettingcited by 20
- 2025OPLoRA: Orthogonal Projection LoRA Prevents Catastrophic Forgetting during Parameter-Efficient Fine-Tuningcited by 20
- 2021How do Quadratic Regularizers Prevent Catastrophic Forgetting: The Role of Interpolationcited by 19
- 2024Disentangling and Mitigating the Impact of Task Similarity for Continual Learningcited by 19
- 2022Sparsity and Heterogeneous Dropout for Continual Learning in the Null Space of Neural Activationscited by 18
- 2023Does Continual Learning Equally Forget All Parameters?cited by 18
- 2024ReSi: A Comprehensive Benchmark for Representational Similarity Measurescited by 18
- 2022Maslow's Hammer for Catastrophic Forgetting: Node Re-Use vs Node Activationcited by 16
- 2023Knowledge Accumulation in Continually Learned Representations and the Issue of Feature Forgettingcited by 16
- 2025Unlocking the Power of Function Vectors for Characterizing and Mitigating Catastrophic Forgetting in Continual Instruction Tuningcited by 16
- 2021Lifelong Learning with Sketched Structural Regularizationcited by 15
- 2021Learning Curves for Continual Learning in Neural Networks: Self-Knowledge Transfer and Forgettingcited by 14
- 2023Layer-wise Auto-Weighting for Non-Stationary Test-Time Adaptationcited by 14
- 2024Optimal Protocols for Continual Learning via Statistical Physics and Control Theorycited by 14
- 2025Optimal Task Order for Continual Learning of Multiple Taskscited by 14
- 2023Overcoming the Stability Gap in Continual Learningcited by 13
- 2024What Variables Affect Out-of-Distribution Generalization in Pretrained Models?cited by 13
- 2024Order parameters and phase transitions of continual learning in deep neural networkscited by 13
- 2022Modelling continual learning in humans with Hebbian context gating and exponentially decaying task signalscited by 12
- 2022Optimizing Class Distribution in Memory for Multi-Label Online Continual Learningcited by 12
- 2022Continual learning: a feature extraction formalization, an efficient algorithm, and fundamental obstructionscited by 11
- 2023Revisiting Single-gated Mixtures of Expertscited by 10
- 2024Accelerating Heterogeneous Federated Learning with Closed-form Classifierscited by 10
50 most cited of 158 All 158 (JSON)
- 2026A Dynamical Theory of LoRA in Continual Learning30 Sep 2026
- 2026RAE-PPG: Duration-Grounded Retain-and-Extend Pretraining for PPG Foundation Models29 Sep 2026
- 2026Neural Succession: A Mesoscopic Theory of Invasion, Coexistence, and Stabilization in Continual Learning28 Sep 2026
- 2026Early Learning Shapes Later Directions Of Representation Change In Continual Learning28 Sep 2026
- 2026Reliable Replay through Spatial Coherence in Online Continual Learning27 Sep 2026
- 2026Learning Dynamics of Continual Learning: A Unified View of Data Attribution, Forgetting, and Plasticity Loss27 Sep 2026
- 2026Meta-learning accelerates detector design optimization22 Sep 2026
- 2026Communication-Efficient LLM Adaptation over Decentralized GPU Meshes13 Sep 2026
- 2026What to Preserve, Where to Adapt: A Depth-Wise Analysis of Forgetting in Continual Gynecological Image Segmentation13 Aug 2026
- 2026Progressive Alignment of Recommender Foundation Model through Multi-Phase Post-Training7 Aug 2026
- 2026Taming the Implicit: Dual-Channel Risk-Aware Reinforcement Fine-Tuning for Continual Multimodal Post-Training4 Aug 2026
- 2026TOOD: Task-Aware Out-of-Distribution Score Calibration for Continual Learners31 Jul 2026
38 more
- 2026Convergence of Continual Learning in Homogeneous Deep Networks29 Jun 2026
- 2026Dimensionality Controls When Modularity Helps in Continual Learning16 Jun 2026
- 2026PEFT-Arena: Understanding Parameter-Efficient Finetuning from a Stability-Plasticity Perspective27 May 2026
- 2026Understanding Imbalanced Forgetting in Rehearsal-Based Class-Incremental Learning14 May 2026
- 2026DynaMiCS: Fine-tuning LLMs with Performance Constraints using Dynamic Mixtures11 May 2026
- 2026When Does Structure Matter in Continual Learning? Dimensionality Controls When Modularity Shapes Representational Geometry30 Apr 2026
- 2026Decomposing the Depth Profile of Fine-Tuning19 Apr 2026
- 2026MiCA Learns More Knowledge Than LoRA and Full Fine-Tuning2 Apr 2026
- 2026Grow, Don't Overwrite: Fine-tuning Without Forgetting9 Mar 2026
- 2026Understanding the Role of Rehearsal Scale in Continual Learning under Varying Model Capacities24 Feb 2026
- 2026Multi-Head Attention as a Source of Catastrophic Forgetting in MoE Transformers13 Feb 2026
- 2026Putting a Face to Forgetting: Continual Learning meets Mechanistic Interpretability29 Jan 2026
- 2026Mechanistic Analysis of Catastrophic Forgetting in Large Language Models During Continual Fine-tuning26 Jan 2026
- 2025Heads collapse, features stay: Why Replay needs big buffers8 Dec 2025
- 2025Data Heterogeneity and Forgotten Labels in Split Federated Learning12 Nov 2025
- 2025OPLoRA: Orthogonal Projection LoRA Prevents Catastrophic Forgetting during Parameter-Efficient Fine-Tuning14 Oct 2025
- 2025Continual Learning with Query-Only Attention1 Oct 2025
- 2025AIM: Adaptive Intra-Network Modulation for Balanced Multimodal Learning27 Aug 2025
- 2025Adapt, But Don't Forget: Fine-Tuning and Contrastive Routing for Lane Detection under Distribution Shift22 Jul 2025
- 2025Exploring Kolmogorov-Arnold Network Expansions in Vision Transformers for Mitigating Catastrophic Forgetting in Continual Learning5 Jul 2025
- 2025The Importance of Being Lazy: Scaling Limits of Continual Learning20 Jun 2025
- 2025Measuring Representational Shifts in Continual Learning: A Linear Transformation Perspective27 May 2025
- 2025Energy-Aware Deep Learning on Resource-Constrained Hardware18 May 2025
- 2025Prototype Augmented Hypernetworks for Continual Learning12 May 2025
- 2025Continual learning for rotating machinery fault diagnosis with cross-domain environmental and operational variations14 Apr 2025
- 2025Hybrid Learners Do Not Forget: A Brain-Inspired Neuro-Symbolic Approach to Continual Learning16 Mar 2025
- 2025Enhanced Continual Learning of Vision-Language Models with Model Fusion12 Mar 2025
- 2025Make Haste Slowly: A Theory of Emergent Structured Mixed Selectivity in Feature Learning ReLU Networks8 Mar 2025
- 2025A Theory of Initialisation's Impact on Specialisation4 Mar 2025
- 2025On-device edge learning for IoT data streams: a survey25 Feb 2025
- 2025Unlocking the Power of Function Vectors for Characterizing and Mitigating Catastrophic Forgetting in Continual Instruction Tuning16 Feb 2025
- 2025Optimal Task Order for Continual Learning of Multiple Tasks5 Feb 2025
- 2024Chained Tuning Leads to Biased Forgetting21 Dec 2024
- 2024Continual Memorization of Factoids in Language Models11 Nov 2024
- 2024Exploring the Stability Gap in Continual Learning: The Role of the Classification Head6 Nov 2024
- 2024Decoupling Semantic Similarity from Spatial Alignment for Neural Networks30 Oct 2024
- 2024Optimal Protocols for Continual Learning via Statistical Physics and Control Theory26 Sep 2024
- 2024CF-KAN: Kolmogorov-Arnold Network-based Collaborative Filtering to Mitigate Catastrophic Forgetting in Recommender Systems25 Aug 2024
50 newest of 158 All 158 (JSON)
- 2023One-Shot Machine Unlearning with Mnemonic Codecited by 2
- 2023One-Shot Machine Unlearning with Mnemonic Code9 Jun 2023
- 2023A Comprehensive Survey of Continual Learning: Theory, Method and Applicationcited by 860
- 2022Surgical Fine-Tuning Improves Adaptation to Distribution Shiftscited by 205
- 2021An Empirical Investigation of the Role of Pre-training in Lifelong Learningcited by 134
- 2021Achieving Forgetting Prevention and Knowledge Transfer in Continual Learningcited by 91
- 2021Continual Learning in the Teacher-Student Setup: Impact of Task Similaritycited by 86
- 2024How Do Large Language Models Acquire Factual Knowledge During Pretraining?cited by 86
- 2022Reliability of CKA as a Similarity Measure in Deep Learningcited by 82
- 2022How catastrophic can catastrophic forgetting be in linear regression?cited by 80
- 2022Probing Representation Forgetting in Supervised and Unsupervised Continual Learningcited by 74
- 2022Teaching Structured Vision&Language Concepts to Vision&Language Modelscited by 71
- 2023Theory on Forgetting and Generalization of Continual Learningcited by 69
- 2022Continual Learning with Foundation Models: An Empirical Study of Latent Replaycited by 61
12 most cited of 147 All 147 (JSON)
- 2026A Dynamical Theory of LoRA in Continual Learning30 Sep 2026
- 2026RAE-PPG: Duration-Grounded Retain-and-Extend Pretraining for PPG Foundation Models29 Sep 2026
- 2026Neural Succession: A Mesoscopic Theory of Invasion, Coexistence, and Stabilization in Continual Learning28 Sep 2026
- 2026Early Learning Shapes Later Directions Of Representation Change In Continual Learning28 Sep 2026
- 2026Reliable Replay through Spatial Coherence in Online Continual Learning27 Sep 2026
- 2026Learning Dynamics of Continual Learning: A Unified View of Data Attribution, Forgetting, and Plasticity Loss27 Sep 2026
- 2026Meta-learning accelerates detector design optimization22 Sep 2026
- 2026Communication-Efficient LLM Adaptation over Decentralized GPU Meshes13 Sep 2026
- 2026What to Preserve, Where to Adapt: A Depth-Wise Analysis of Forgetting in Continual Gynecological Image Segmentation13 Aug 2026
- 2026Taming the Implicit: Dual-Channel Risk-Aware Reinforcement Fine-Tuning for Continual Multimodal Post-Training4 Aug 2026
- 2026TOOD: Task-Aware Out-of-Distribution Score Calibration for Continual Learners31 Jul 2026
- 2026Convergence of Continual Learning in Homogeneous Deep Networks29 Jun 2026
12 newest of 147 All 147 (JSON)