IC-529For inconsistent knowledge in GPT-2, Llama2-7B, and Llama3-8B, the knowledge neurons are associated with the specific query rather than the fact, as shown by differential effects of suppressing or enhancing query-specific versus neighbor neurons

Yuheng Chen, Pengfei Cao, Yubo Chen, Kang Liu, Jun Zhao

SourceKnowledge Localization: Mission Not Accomplished? Enter Query Localization!

The authors intervene on neuron activations by suppressing or enhancing them and measure the change in answer probability. For Ki facts, manipulating the query's own neurons (ni) has a large effect on the answer, while manipulating the union, intersection, or refined set of neighbor neurons has a much smaller effect. For Kc facts, the decrease in effect for neighbor neurons is less pronounced. This demonstrates that for Ki, the same fact is stored in different neurons depending on which paraphrase is used to query it, violating the assumption of a fixed fact-to-neuron mapping.

Evidence
interventional
Caveat
The specific magnitude of the differential effect is shown only in Figure 4 (violin/bar plots) without tabulated values in the text. The threshold for classifying Kc vs Ki is set very low to be conservative, meaning some Kc facts may not be fully consistent.
Model
GPT-2, Llama 2 / Llama 2 base Llama 2 7B, Llama 3 8B
Datasets
ParaRel [eval]
Related work
Knowledge Neurons in Pretrained Transformers [builds-on]
Related findings
IC-528, IC-530
Extraction
automatic-extraction