What does it mean that distinguish signal from narration?

Your mind narrates continuously but only some of that narration contains actionable signal. Most of your mental content is reruns — repetitive, self-referential, habitual. Learning to tell the difference is the first act of cognitive filtering.

Example: An engineering lead sits in a design review. Her mind generates three streams simultaneously: a genuine technical insight about a caching layer that could eliminate the latency problem, a thread of social anxiety ('do they think I'm senior enough to be leading this?'), and a reheated opinion about microservices she's held for three years. Only one of these is signal — novel, actionable, and responsive to the current situation. The other two are narration on autopilot.

Try this: Set a timer for 3 minutes. Write down every thought that crosses your mind — stream of consciousness, no filtering. When the timer stops, go back through the list and tag each thought: S for Signal (novel, actionable, surprising, responsive to a real problem) or N for Narration (repetitive, self-referential, habitual, defensive). Count the ratio. Most people find 70-80% narration on the first pass. That ratio is your baseline noise floor.