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Stephen Porges, PhD

Stephen Porges, PhD, speaks about the Polyvagal Theory, healing trauma and PTSD, and his own psychological and spiritual journey.

We learn that Dr. Porges was a clarinetist, a practice he likens to pranayama yoga.*

Benny Goodman on clarinet.

We also learn that he first became interested in human psychology as a result of his experiences in childhood.

 The Polyvagal Theory: A New Understanding of the Nervous System

Stephen Porges’ Polyvagal theory significantly reworks our understanding of how the nervous system responds to threat and trauma.  As Elizabeth explains in an upcoming article, the new theory is relevant both to mediation and to healing trauma.

Overview of the Autonomic Nervous System

By way of background, the Autonomic Nervous System (ANS),  a part of the peripheral nervous system, regulates internal organ functions, such as heart rate, digestion rate and pupil dilation.  It also responds to trauma or threat.

The ANS is usually conceptualized as consisting of two branches, the sympathetic and parasympathetic nervous systems.  The sympathetic nervous system activates the body, especially during emergencies (“fight-or-flight”); the parasympathetic is calming (“rest-and-digest”).

The balance between the two systems is usually said to determine ANS functioning.

The Ventral Vagus Nerve

Dr. Porges has expanded our view of the  subject by emphasizing a third factor:  the vagus nerve and its role, through its branches, in regulating the heart, face, abdominal viscera and breath.  It also communicates with the brain.

Vagus Nerve
The Vagus Nerve

“Social Engagement” and Conflict Resolution

The vagus nerve, or more precisely the ventral branch of the vagus nerve,  controls the muscles of the face, heart and lungs — parts of the body used to interact with others. This distinctively mammalian system thus fosters what Porges calls “social engagement.”

According to Dr. Porges, social engagement, in turn, tends to “down regulate” (calm) the sympathetic nervous system, and the fight response.

Stated another way,  it is in large part through our face/heart/brain connection, mediated by the ventral vagus nerve, that we learn to temper our responses to interpersonal threats and challenges.

In Elizabeth’s view, this calming aspect of  “social engagement,” via the vagus nerve, helps explain the neurobiology of the “magic” of effective mediation and the IDR cycle.

The Dorsal Vagus Nerve

Another branch of the vagus, the dorsal vagus, regulates organs below the diaphragm.  It is instrumental in activating the “shutdown” of the body seen in cases of overwhelming trauma.  From an evolutionary standpoint, this is a much older part of the nervous system.

Recent modalities for healing trauma, such as Peter Levine’s Somatic Experiencing, which Elizabeth has been studying intensively for the last three years, use details from Dr. Porges’ description of dorsal and ventral vagal functioning to develop gentle, somatically based strategies for releasing trauma.

. . .

 * As Dr. Porges has frequently observed, the ventral vagus also regulates activities such as playing wind instruments like the clarinet. These practices involve both regulating the breath (like pranayma) and engagement with others.

** Also note that technically the vagus is actually a part of the parasympathetic nervous system.  This point cannot be dealt with fully here for reasons of space.