DeepMind 新研究:推理时回灌深层激活可降困惑度

Rohan Paul · @rohanpaul_ai · X·2026-08-25 10:07·28分钟前
AI 导读

Google DeepMind 新论文提出“Recirculation”方法:推理时将深层激活的一小部分混入浅层,权重不变,即可恢复模型在长上下文中丢失的部分状态。在 Gemma3 上,10 个语言建模数据集中 9 个困惑度下降,12B 模型最高降 35%,但多项选择收益有限;该方法无需重训,但代价是预填充无法并行,且收益不跨模型家族迁移。

Rohan Paul@rohanpaul_ai
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DeepMind 新研究:推理时回灌深层激活可降困惑度

2026-08-25 10:07· 28分钟前
AI 导读

Google DeepMind 新论文提出“Recirculation”方法:推理时将深层激活的一小部分混入浅层,权重不变,即可恢复模型在长上下文中丢失的部分状态。在 Gemma3 上,10 个语言建模数据集中 9 个困惑度下降,12B 模型最高降 35%,但多项选择收益有限;该方法无需重训,但代价是预填充无法并行,且收益不跨模型家族迁移。

New Google DeepMind paper shows, a transformer's shallow layers never see what its deeper layers have already worked out about the context. Leaking a little of it back down during inference recovers part of what was lost.

So if your model keeps losing state over a long input, the fix may not need retraining, though the cost moves to prefill, which can no longer run in parallel.

The paper shows this working on frozen weights, but the size of the benefit does not transfer across model families.

Recirculation mixes a small fraction of a deep layer's activations into a shallow layer at the next input step, weights untouched, and sets that against the off-the-shelf model.

On Gemma3, perplexity drops on 9 of 10 language-modeling datasets, by as much as 35% for the 12B model, though multiple-choice gains are modest.

– arxiv. org/abs/2608.17981

Title: "Recirculation"