The AI refusal switch may live in 0.1% of neurons

Nous Research proposes CNA, a method that uses contrastive prompts to find a tiny set of MLP neurons tied to refusal behavior. The interesting point is not just jailbreaks, but what this says about alignment fine-tuning.

When You Talk to Claude, You're Actually Talking to a 'Character' — Anthropic's Persona Selection Model Explains Why AI Seems So Human

Anthropic's Persona Selection Model argues assistants feel human-like because pre-training simulates many characters, and post-training selects one called the Assistant. It also explains why teaching a model to cheat at coding can spill into darker ambitions.