Papers › Addressing Some Limitations of Transformers with Feedback Memory
Addressing Some Limitations of Transformers with Feedback Memory
Angela Fan, Thibaut Lavril, Edouard Grave, Armand Joulin, Sainbayar Sukhbaatar
Transformers have been successfully applied to sequential, auto-regressive tasks despite being feedforward networks. Unlike recurrent neural networks, Transformers use attention to capture temporal relations while processing input tokens in parallel. While this parallelization makes them computationally efficient, it restricts the model from fully exploiting the sequential nature of the input. The representation at a given layer can only access representations from lower layers, rather than the higher level representations already available. In this work, we propose the Feedback Transformer architecture that exposes all previous representations to all future representations, meaning the lowest representation of the current timestep is formed from the highest-level abstract representation of the past. We demonstrate on a variety of benchmarks in language modeling, machine translation, and reinforcement learning that the increased representation capacity can create small, shallow models with much stronger performance than comparable Transformers.
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Code
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Code Syntology ran Syntology
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Tasks
Results from the paper archive 2025-07-28
| Task | Dataset | Model | Metric | Value | Rank at snapshot | Leaderboard | Report |
|---|---|---|---|---|---|---|---|
| Language Modelling | Penn Treebank (Character Level) | Feedback Transformer | Bit per Character (BPC) | 1.160 | #5 of 20 | Archive leaderboard | report |
| Language Modelling | Penn Treebank (Character Level) | Feedback Transformer | Number of params | 10.7M | #5 of 20 | Archive leaderboard | report |
| Language Modelling | WikiText-103 | Feedback Transformer (8 layers) | Number of params | 139M | #32 of 89 | Archive leaderboard | report |
| Language Modelling | WikiText-103 | Feedback Transformer (8 layers) | Test perplexity | 18.2 | #32 of 89 | Archive leaderboard | report |
| Language Modelling | WikiText-103 | Feedback Transformer (8 layers) | Validation perplexity | 17.5 | #32 of 89 | Archive leaderboard | report |
| Language Modelling | WikiText-103 | Feedback Transformer (4 layers) | Number of params | 44M | #47 of 89 | Archive leaderboard | report |
| Language Modelling | WikiText-103 | Feedback Transformer (4 layers) | Test perplexity | 22.4 | #47 of 89 | Archive leaderboard | report |
| Language Modelling | WikiText-103 | Feedback Transformer (4 layers) | Validation perplexity | 21.4 | #47 of 89 | Archive leaderboard | report |
| Language Modelling | enwik8 | Feedback Transformer | Bit per Character (BPC) | 0.96 | #6 of 42 | Archive leaderboard | report |
| Language Modelling | enwik8 | Feedback Transformer | Number of params | 77M | #6 of 42 | Archive leaderboard | report |
Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.
Methods
Introduced by this paper: Feedback Memory, Feedback Transformer
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