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arxiv: 2601.21367 · v1 · submitted 2026-01-29 · 💻 cs.AI · cs.LG

Hebbian Learning with Global Direction

Pith reviewed 2026-05-16 10:16 UTC · model grok-4.3

classification 💻 cs.AI cs.LG
keywords Hebbian learningglobal guidanceOja's rulebackpropagation alternativeneural network trainingImageNet
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The pith

A sign-based global signal steers local Hebbian updates to reach competitive accuracy on ImageNet.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper shows that pure local Hebbian plasticity cannot scale because it ignores task objectives. Adding a single global sign signal, derived from the overall loss direction, tells each local update whether to strengthen or weaken its connections. Local updates follow Oja's rule plus competition for stability. The resulting framework trains both small and large networks on standard image datasets and narrows the accuracy gap to backpropagation without changing network architecture.

Core claim

The Global-guided Hebbian Learning framework combines Oja's rule with competitive learning at the local level and a sign-based global direction signal that modulates the polarity of those local updates. This integration allows the same local plasticity rule to respect global task goals across different network depths and widths, producing results that are competitive with backpropagation on ImageNet.

What carries the argument

The sign-based global signal that broadcasts the direction of the task objective and flips the sign of local Hebbian weight changes accordingly.

Load-bearing premise

A single sign broadcast from the global loss is enough to align local Hebbian changes with the task objective on any network size or dataset.

What would settle it

Train the same large convolutional network on ImageNet with the proposed method and measure whether top-1 accuracy stays more than a few percentage points below a matched backpropagation baseline.

read the original abstract

Backpropagation algorithm has driven the remarkable success of deep neural networks, but its lack of biological plausibility and high computational costs have motivated the ongoing search for alternative training methods. Hebbian learning has attracted considerable interest as a biologically plausible alternative to backpropagation. Nevertheless, its exclusive reliance on local information, without consideration of global task objectives, fundamentally limits its scalability. Inspired by the biological synergy between neuromodulators and local plasticity, we introduce a novel model-agnostic Global-guided Hebbian Learning (GHL) framework, which seamlessly integrates local and global information to scale up across diverse networks and tasks. In specific, the local component employs Oja's rule with competitive learning to ensure stable and effective local updates. Meanwhile, the global component introduces a sign-based signal that guides the direction of local Hebbian plasticity updates. Extensive experiments demonstrate that our method consistently outperforms existing Hebbian approaches. Notably, on large-scale network and complex datasets like ImageNet, our framework achieves the competitive results and significantly narrows the gap with standard backpropagation.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 1 minor

Summary. The paper proposes a Global-guided Hebbian Learning (GHL) framework that augments local Oja-rule plasticity with a sign-based global signal to overcome the scalability limits of purely local Hebbian learning, claiming consistent outperformance over prior Hebbian methods and competitive ImageNet results that narrow the gap with backpropagation.

Significance. If the performance claims are substantiated with reproducible metrics, the work would be significant for providing a model-agnostic mechanism to inject global task information into local updates while retaining Hebbian locality, potentially advancing biologically motivated alternatives to backpropagation.

major comments (2)
  1. [Abstract] Abstract: the central claim that the framework 'achieves the competitive results and significantly narrows the gap with standard backpropagation' on ImageNet supplies no numerical accuracy values, baseline comparisons, error bars, or experimental protocol details, leaving the performance assertion without verifiable support.
  2. [Framework description] Framework section (global component): the source of the sign-based global signal is unspecified. If the sign is computed from loss gradients (sign(∇L)), the method implicitly requires backpropagation for the global direction, undermining both the 'Hebbian' label and the claimed computational savings relative to standard backprop.
minor comments (1)
  1. Clarify whether the global signal is supplied externally, derived from output error, or obtained via any non-local computation, and state this explicitly in the method description.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive comments. We address each major point below and have revised the manuscript to improve clarity and verifiability.

read point-by-point responses
  1. Referee: [Abstract] Abstract: the central claim that the framework 'achieves the competitive results and significantly narrows the gap with standard backpropagation' on ImageNet supplies no numerical accuracy values, baseline comparisons, error bars, or experimental protocol details, leaving the performance assertion without verifiable support.

    Authors: We agree that the abstract would benefit from explicit numerical support. The full experimental results (including ImageNet top-1 accuracies, comparisons to prior Hebbian baselines, standard deviations over multiple runs, and protocol details) are already reported in Section 4 and the associated tables. In the revised manuscript we will insert the key figures directly into the abstract (e.g., GHL accuracy, best prior Hebbian accuracy, and back-propagation accuracy) together with a pointer to the experimental section, making the claim immediately verifiable. revision: yes

  2. Referee: [Framework description] Framework section (global component): the source of the sign-based global signal is unspecified. If the sign is computed from loss gradients (sign(∇L)), the method implicitly requires backpropagation for the global direction, undermining both the 'Hebbian' label and the claimed computational savings relative to standard backprop.

    Authors: The sign-based global signal is not obtained via back-propagated loss gradients. As stated in Section 3, it is a model-agnostic, broadcast global direction derived from the task objective in a neuromodulator-like fashion that does not require layer-wise gradient computation or propagation. Consequently the local Oja updates remain strictly local and the overall procedure retains its computational advantage over full back-propagation. We have expanded the framework description in the revision to state the exact origin of the sign signal and to contrast it explicitly with gradient-based methods, removing any ambiguity. revision: yes

Circularity Check

0 steps flagged

No significant circularity in derivation chain

full rationale

The paper introduces an original GHL framework that combines local Oja's rule with a new sign-based global signal, presented as a biologically inspired integration rather than a re-expression of prior fitted parameters or self-citations. No equations or load-bearing steps in the provided abstract reduce the claimed ImageNet performance gains to tautological redefinitions of inputs; the method is described as model-agnostic with experimental validation, keeping the central claims independent of circular reductions.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 1 invented entities

The framework rests on standard assumptions from prior Hebbian literature and introduces one new guidance mechanism without independent falsifiable evidence supplied in the abstract.

axioms (1)
  • domain assumption Oja's rule yields stable local weight updates when combined with competitive learning
    Invoked as the local component without derivation in the abstract.
invented entities (1)
  • sign-based global signal no independent evidence
    purpose: To provide directional guidance to local Hebbian plasticity updates based on global task objectives
    New mechanism introduced to overcome the locality limitation of pure Hebbian learning.

pith-pipeline@v0.9.0 · 5489 in / 1345 out tokens · 34516 ms · 2026-05-16T10:16:25.880056+00:00 · methodology

discussion (0)

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Reference graph

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39 extracted references · 39 canonical work pages · 1 internal anchor

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    Hebbian Learning with Global Direction

    INTRODUCTION Deep Neural Networks (DNNs) have achieved revolutionary success in recent years, with Backpropagation (BP) playing an important role. Despite its remarkable achievements, BP still has some limita- tions such as the weight transport problem [1]. Also, BP’s reliance on the precise, global propagation of error signals lacks local plastic- ity, m...

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    METHOD 2.1. Overview of GHL framework The three-factor learning rule provides a model for synaptic plastic- ity. It posits that the change in a synaptic weight∆w ik is governed by two components: a local Hebbian termH(pre i,post k), which de- pends on pre- and post-synaptic activities, and a global modulatory signalG(m). The three-factor learning rule is ...

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    EXPERIMENTS AND RESULTS 3.1. Comparison with existing Hebbian methods on CIFAR-10 and CIFAR-100 datasets To evaluate our method, we first conducted a rigorous comparison against state-of-the-art Hebbian algorithms on the CIFAR-10/100 datasets [28]. These methods include SoftHebb [11, 12], FastHebb (SWTA-FH/HPCA-FH) [7, 14, 15], and HWTA-BCM [13]. To en- s...

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    Table 4 shows that our method maintains robust performance without significant degradation as depth increases, even with ex- tremely deep networks, confirming the scalability and effectiveness of our GHL framework. Arch VGG [33] ResNet [34] Layers 14 16 20 32 44 56 110 1202 Params 14.71 33.63 0.27 0.46 0.66 0.85 1.72 19.33 Acc 89.2989.48 86.72 86.86 87.09...

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