English

DISCO: Disentangled Communication Steering for Large Language Models

Machine Learning 2025-09-23 v1

Abstract

A variety of recent methods guide large language model outputs via the inference-time addition of steering vectors to residual-stream or attention-head representations. In contrast, we propose to inject steering vectors directly into the query and value representation spaces within attention heads. We provide evidence that a greater portion of these spaces exhibit high linear discriminability of concepts --a key property motivating the use of steering vectors-- than attention head outputs. We analytically characterize the effect of our method, which we term DISentangled COmmunication (DISCO) Steering, on attention head outputs. Our analysis reveals that DISCO disentangles a strong but underutilized baseline, steering attention inputs, which implicitly modifies queries and values in a rigid manner. In contrast, DISCO's direct modulation of these components enables more granular control. We find that DISCO achieves superior performance over a number of steering vector baselines across multiple datasets on LLaMA 3.1 8B and Gemma 2 9B, with steering efficacy scoring up to 19.1% higher than the runner-up. Our results support the conclusion that the query and value spaces are powerful building blocks for steering vector methods.

Keywords

Cite

@article{arxiv.2509.16820,
  title  = {DISCO: Disentangled Communication Steering for Large Language Models},
  author = {Max Torop and Aria Masoomi and Masih Eskandar and Jennifer Dy},
  journal= {arXiv preprint arXiv:2509.16820},
  year   = {2025}
}
R2 v1 2026-07-01T05:47:44.134Z