Impact of Disabling Hallucination Neurons on LLM Coding Performance
A community discussion has emerged exploring whether disabling "hallucination neurons" (H-Neurons)—a sparse subset of neurons linked to factual errors—could improve LLM performance on complex coding benchmarks like DeepSWE. If disabling H-Neurons successfully reduces logical and factual errors without degrading overall reasoning, it could significantly boost the reliability of AI coding agents. This approach offers a potential alternative to heavy fine-tuning or reinforcement learning for hallucination mitigation. Research indicates that H-Neurons make up less than 0.1% of an LLM's neural network, yet they can reliably predict and trigger hallucinations. However, permanently disabling these neurons risks "lobotomizing" other capabilities of the model, making dynamic correction frameworks like LLM-CAS a potential alternative.
## BACKGROUND
The concept of H-Neurons stems from a December 2025 paper by Tsinghua University researchers, which identified specific neurons responsible for LLM hallucinations. DeepSWE is a contamination-free, long-horizon software engineering benchmark designed to test the coding capabilities of advanced AI agents under realistic conditions.