Polyvagal-Informed Therapy vs Somatic Experiencing

A side-by-side comparison: mechanism, evidence, the conditions each treats, philosophical roots, and where they actually disagree clinically.

At a glance

Polyvagal-Informed Therapy

Tradition
Somatic
Founder
Porges / Dana (2011)
Evidence
Emerging evidence
Focus
Somatic + Relational
Format
Individual
Duration
Framework

Somatic Experiencing

Tradition
Somatic
Founder
Peter Levine (1997)
Evidence
RCT-supported
Focus
Somatic + Experiential
Format
Individual
Duration
Medium-term

How they work

Polyvagal-Informed Therapy

Core mechanism: Identifying autonomic state (ventral/sympathetic/dorsal) + co-regulation with therapist + building ventral vagal capacity

Ontology: Trauma disrupts autonomic regulation; neuroception of danger keeps nervous system in defensive states

Somatic Experiencing

Core mechanism: Titrated pendulation between activation and resource states completes truncated survival responses trapped in the body

Ontology: Incomplete defensive responses (fight/flight/freeze) remain bound in the nervous system as undischarged survival energy

Conditions treated

3 shared · 1 Polyvagal-Informed Therapy-only · 3 Somatic Experiencing-only

What each assumes — and misses

Polyvagal-Informed Therapy

Philosophical roots: Porges (polyvagal theory); Darwin (emotional expression); Merleau-Ponty (body-subject); Dana (clinical application); Levine (somatic trauma)

Blind spots: Underlying theory scientifically contested; clinical applications extrapolate beyond evidence; not a standalone protocol

Therapeutic voice: That shutdown feeling — that's your nervous system protecting you. It makes sense. Let's see if we can find a little more safety right now.

Somatic Experiencing

Philosophical roots: Reich/Lowen (body holds defense — Levine studied with both); Merleau-Ponty (lived body); Darwin (survival instincts); ethology (Tinbergen, Lorenz — animal defensive responses); James-Lange (emotion as bodily process)

Blind spots: Risk of over-physiologizing psychological meaning; limited manualization makes research difficult; can be vague in application

Therapeutic voice: Where in your body do you feel that right now? Just notice, without trying to change it.

Choosing between them

Polyvagal-Informed Therapy and Somatic Experiencing both sit within the Somatic tradition — they share a worldview about what suffering is and how change happens. Differences are more often about technique and emphasis than about underlying theory.

For deeper coverage: see the full Polyvagal-Informed Therapy and Somatic Experiencing pages, or use the interactive comparison tool to add more modalities to this comparison.