Polyvagal theory, developed by Stephen Porges, maps the hierarchical organization of the autonomic nervous system and explains how safety and danger signals shape the body's moment-to-moment state. The three circuits — ventral vagal (social engagement), sympathetic (mobilization), and dorsal vagal (shutdown) — correspond precisely to different phenomenological qualities of experience. Understanding which circuit is active transforms diagnosis from symptom-labeling to a legible reading of the body's intelligent response to perceived conditions.
Each step builds on the last.