Basics of polyvagal theory

In today's episode, I welcome my friend Marcella Cox back to the podcast.

Marcella is a certified IFS therapist, approved consultant, and somatic IFS assistant trainer. She's also a certified Safe and Sound Protocol (SSP) and Rest and Restore provider, and the lead author of the new guidelines for integrating IFS with these listening therapies.

We talk about:

• The basics of polyvagal theory

• How our nervous system states impact our parts

• Why co-regulation is central to healing

• The difference between SSP (connection to others) and Rest and Restore (connection to Self)

• How listening therapies can support safety in the body and allow more Self Energy to emerge

I also share my own experience trying SSP with Marcella. I experienced some surprising physical shifts and insights that came up after a few short listening sessions.

If you're curious about nervous system regulation and how it can deepen your IFS work, I think you'll really appreciate this conversation.

Marcella Cox, LMFT, is a therapist, author, and presenter devoted to exploring the intersection of embodiment, trauma healing, and eating disorder recovery. She is a Level 3 Certified IFS Therapist, an Approved IFS Clinical Consultant, and an Assistant Trainer for Somatic IFS, the model developed by Susan McConnell.

She provides consultation and leads workshops, trainings, and retreats for professionals on IFS for disordered eating, Somatic IFS, and integrating IFS with the Safe & Sound Protocol and is the lead author of the IFS and Listening Therapies (Safe and Sound Protocol and Rest and Restore Protocol) Combined Delivery Guidelines, published through Unyte in January 2026.

Marcella is the founder and executive director of Kindful Body, which provides online therapy and nutrition counseling for eating and body concerns in California. She is also the co-founder of the IFS Consultation Collective, offering weekly consultation with IFS lead trainers.

To learn more about combining IFS and Unyte's listening therapies: https://integratedlistening.com/resources/ifs-and-listening-therapies/

Marcella's SSP & IFS groups: https://www.kindfulbody.com/somatic-ifs-and-ssp-group/

Sign up for Marcella's newsletter to find out about upcoming offerings

Kindful Body on Instagram - https://www.instagram.com/kindfulbody/

This episode is sponsored by Therapy Training Boston.

Therapy Training Boston offers live, in-person, and online workshops, plus consultation for therapists and other helping professionals, designed to support you as a whole person while satisfying your CE requirements. All of their offerings are taught with an eye toward context, power, and relational justice, and draw on the family systems theories and best practices that shaped the IFS model. They also offer an Intensive Certificate Program in Couples and Family Therapy to help you build confidence and capacity in community.

I started this podcast to help spread IFS out into the world and make the model more accessible to everyone. Seven years later, that's still at the heart of all we do.

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