You have probably heard of the vagus nerve, and (whether you realize it or not) have been exposed to some of the concepts of Polyvagal Theory in yoga classes. In fact, we have discussed the theory in a previous episode of the podcast.
In today's episode, host Rachel Land and Yoga Medicine Therapeutic Specialist Valerie Knopik, PhD, revisit Polyvagal Theory and explore the latest scientific debate it has generated. They break down the original framework, the newer criticisms, and the ways scientific ideas evolve over time.
The conversation stays grounded in real-world teaching, especially around stress response, breath, and the role of relationships in helping people feel safe enough to practice. It is a thoughtful reminder that research can shift while the practical value of awareness, connection, and regulation remains central to yoga.
"Science is never stagnant, and that's part of the beauty of science for me." — Valerie Knopik.
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What You'll Learn:
Vagus nerve roles in stress and relaxation response [3:24]
Recent papers updating and challenging Polyvagal Theory (PVT) [4:41]
The nature of the scientific method [7:12]
Defining PVT [10:37]
Summarizing the current controversy: over-simplification of dorsal vs ventral vagus [25:29]
Other points of contention: dorsal vagal and trauma response, heart rate variability as a measure of vagal tone, clinical over-use [31:41]
Relevance to yoga teaching and practice [37:11]
The "science of safety" in yoga: Yoga Medicine Mental Health & Wellness Teacher Training [44:00]
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Links Mentioned:
Watch this episode on YouTube
Mental Health & Wellness Yoga Teacher Training
Yoga Medicine Podcast Research Roundup: Updates on Polyvagal Theory
Porges SW. Polyvagal Theory: Current Status, Clinical Applications, and Future Directions. Clin Neuropsychiatry. 2025 Jun;22(3):169-184. doi: 10.36131/cnfioritieditore20250301. PMID: 40735382; PMCID: PMC12302812
Grossman P et al. Why The Polyvagal Theory Is Untenable: An international expert evaluation of the polyvagal theory and commentary upon Porges, S.W. (2025). Clin. Neuropsychiatry, 22(3), 169-184. Clin Neuropsychiatry. 2026 Feb;23(1):100-112. doi: 10.36131/cnfioritieditore20260110. PMID: 41768017; PMCID: PMC12937499
Yoga Medicine Podcast Episodes:
Epigenetics, Mental Health & Yoga
The Neuroscience of Resilience
Interoception Research & Yoga
Connect with Valerie Knopik, PhD: Facebook | Instagram | X | YMO Teacher
Learn More:
Find the full show notes at YogaMedicine.com/podcast-166.
Learn more about insider tips, online classes or information on our teacher trainings at YogaMedicine.com.
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