Difference Target Propagation
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Abstract (arXiv)
Back-propagation has been the workhorse of recent successes of deep learning but it relies on infinitesimal effects (partial derivatives) in order to perform credit assignment. This could become a serious issue as one considers deeper and more non-linear functions, e.g., consider the extreme case of nonlinearity where the relation between parameters and cost is actually discrete. Inspired by the biological implausibility of back-propagation, a few approaches have been proposed in the past that could play a similar credit assignment role. In this spirit, we explore a novel approach to credit assignment in deep networks that we call target propagation. The main idea is to compute targets rather than gradients, at each layer. Like gradients, they are propagated backwards. In a way that is related but different from previously proposed proxies for back-propagation which rely on a backwards network with symmetric weights, target propagation relies on auto-encoders at each layer. Unlike back-propagation, it can be applied even when units exchange stochastic bits rather than real numbers. We show that a linear correction for the imperfectness of the auto-encoders, called difference target propagation, is very effective to make target propagation actually work, leading to results comparable to back-propagation for deep networks with discrete and continuous units and denoising auto-encoders and achieving state of the art for stochastic networks.
Key facts. Cited by 144 papers in the map (data through 7 Oct 2026). First posted on arXiv 23 Dec 2014.
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Citing papers per year: 2021: 27; 2022: 23; 2023: 21; 2024: 21; 2025: 22; 2026: 30.
144 papers.
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50 most cited of 144 All 144 (JSON)
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50 newest of 144 All 144 (JSON)
- 2021A Survey of Quantization Methods for Efficient Neural Network Inferencecited by 798
- 2023Uncovering mesa-optimization algorithms in Transformerscited by 94
- 2021Predictive Coding: a Theoretical and Experimental Reviewcited by 74
- 2021On Training Implicit Modelscited by 73
- 2021Revisiting Locally Supervised Learning: an Alternative to End-to-end Trainingcited by 71
- 2022Scaling Forward Gradient With Local Lossescited by 65
- 2023When Do Transformers Shine in RL? Decoupling Memory from Credit Assignmentcited by 62
- 2022Holomorphic Equilibrium Propagation Computes Exact Gradients Through Finite Size Oscillationscited by 40
- 2022Low-Pass Filtering SGD for Recovering Flat Optima in the Deep Learning Optimization Landscapecited by 39
- 2023The Predictive Forward-Forward Algorithmcited by 35
- 2023Brain-inspired Computational Intelligence via Predictive Codingcited by 30
- 2021Credit Assignment in Neural Networks through Deep Feedback Controlcited by 28
12 most cited of 142 All 142 (JSON)
- 2026The Price of Locality: Why Forward-Forward Underperforms Backpropagation?27 Sep 2026
- 2026LocalProp: Neuro-Localized Memory-Efficient Backpropagation26 Sep 2026
- 2026The Ups and Downs of Backprop Weights18 Sep 2026
- 2026Learning in Deep Networks under Dale's Constraint7 Aug 2026
- 2026Conditioned Direct Feedback Alignment via Activity and Error Geometry20 Jul 2026
- 2026Constrained Hebbian Learning Supports Efficient Representational Allocation under Structural Constraints17 Jul 2026
- 2026Weight Feedback Computes the Jacobian Transpose Locally in Modern Deep Networks15 Jul 2026
- 2026Muon as a Residual Connection1 Jul 2026
- 2026Diffusing Blame: Task-Dependent Credit Assignment in Biologically Plausible Dual-Stream Networks30 Jun 2026
- 2026Forget, Anticipate and Adapt: Test Time Training for Long Videos25 Jun 2026
- 2026Decentralised AI Training and Inference with BlockTrain23 Jun 2026
- 2026Breaking Chains with Trees: Model-Parallel Deep Learning with O(log N) Time Complexity19 Jun 2026
12 newest of 142 All 142 (JSON)