Papers › Knowledge Neurons in Pretrained Transformers

Knowledge Neurons in Pretrained Transformers

18 Apr 2021ACL 2022 5arXiv:2104.08696archive 2025-07-28

Damai Dai, Li Dong, Yaru Hao, Zhifang Sui, Baobao Chang, Furu Wei

Large-scale pretrained language models are surprisingly good at recalling factual knowledge presented in the training corpus. In this paper, we present preliminary studies on how factual knowledge is stored in pretrained Transformers by introducing the concept of knowledge neurons. Specifically, we examine the fill-in-the-blank cloze task for BERT. Given a relational fact, we propose a knowledge attribution method to identify the neurons that express the fact. We find that the activation of such knowledge neurons is positively correlated to the expression of their corresponding facts. In our case studies, we attempt to leverage knowledge neurons to edit (such as update, and erase) specific factual knowledge without fine-tuning. Our results shed light on understanding the storage of knowledge within pretrained Transformers. The code is available at https://github.com/Hunter-DDM/knowledge-neurons.

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parse_kn hunter-ddm/knowledge-neurons/src/2_get_kn.py official repository ran · our draft was wrong MIT (permissive) · 2fa69435832209b8 · report
KnowledgeNeurons EleutherAI/knowledge-neurons/knowledge_neurons/knowledge_neurons.py community (archive-listed) ran MIT (permissive) · e01867c63efbe404 · report
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AdamAttentionAttention DropoutBERTDense ConnectionsDropoutLayer NormalizationLinear LayerLinear Warmup With Linear DecayMulti-Head AttentionResidual ConnectionSoftmaxWeight DecayWordPiece

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