Module 3: Nervous System States - Parasympathetic, Sympathetic, and Dorsal Vagal Responses

Explore the three states of the nervous system and how understanding polyvagal theory transforms trauma-informed practice.

March 29, 2026
13 min read
Brain Science

Module 3: Nervous System States

The autonomic nervous system has three primary states: parasympathetic (rest and digest), sympathetic (fight or flight), and dorsal vagal (freeze or shutdown). This module teaches professionals to recognize which nervous system state a trauma survivor is in and how to respond appropriately.

Participants learn how to identify signs of each state, understand why trauma survivors may cycle between states, and develop strategies for helping the nervous system return to regulation. This knowledge transforms how professionals interpret and respond to trauma responses.

A Neurodevelopment Lens

From a neurodevelopment perspective, children who experience developmental trauma often become stuck in dysregulated nervous system states. Their nervous systems learn to default to hypervigilance, shutdown, or chaotic activation rather than the calm, alert state needed for learning and connection. Understanding nervous system states through a developmental lens helps professionals recognize that a child's "difficult" behavior is often a sign of nervous system dysregulation rooted in early trauma. Healing requires helping the nervous system reorganize through safety, predictability, and co-regulation with trusted adults.

**Learn to recognize and respond to nervous system dysregulation.**

Explore the Full Training Course

Key Topics Covered

nervous systempolyvagalparasympatheticsympatheticvagal
Share This Article
Share this article:

Help spread awareness about trauma recovery and neurobiology by sharing this article with your network.

Continue Reading

Explore more articles on related topics to deepen your understanding

Explore More Articles

Discover more insights on trauma recovery, neurobiology, and building trauma-responsive organizations.