There is no such thing as “Polyvagal Therapy.”
When we talk about Polyvagal, we refer to a theory developed by Stephen Porges that describes the autonomic nervous system (ANS) differently than it was conceptualized before.
Porges focused initially in the way the ANS is influenced by the central nervous system, sensitive to afferent influences, characterized by an adaptive reactivity dependent on the evolutionary development of the neural circuits, and interactive with source nuclei in the brainstem regulating the striated muscles of the face and head.
The Polyvagal Theory challenged the previous understanding of the ANS in the following ways:
The ANS was classically divided into two subdivisions, the sympathetic and the parasympathetic and it was believed there was a paired antagonism between them, meaning that one is inhibited with the activation of the other, and that the vagus nerve was a single unit (the vagus is the principal nerve of the parasympathetic system).
Porges' theory, in contrast, provided us with a divergent view of the relationship between the principal branches of the ANS and the vagus nerve itself by considering the relationship between evolution and trauma. Porges differentiates brainstem areas that regulate the organs situated above the diaphragm (branching to the face, head, lungs, and heart) from those regulating below the diaphragm (gut), depending on the myelinated and unmyelinated vagal pathways (ramifications of the vagus nerve extend from the head to the abdomen; myelinated refers to a fat layer covering the nerve, and myelinated nerves send.
He differentiates between two branches of the Vagus Nerve: the ventral which is myelinated —newer, optimized, only on mammals — and the dorsal which is unmyelinated —older, primitive, shared by all vertebrates.
Porges’ main contribution is saying that the ANS is a system of three circuits in which newer circuits inhibit older circuits; that the ANS functioning is hierarchical instead of antagonistic (or looking only for equilibrium); and that the newest vagus controls vocalization and face expression-recognition as an added survival strategy.
Even when he emphasized the connection between the ANS reactions to facial expressions and tone of voice, his theory was very relevant to the Trauma community since the vagus is directly correlated to the dysregulation of the nervous system that happens after traumatization.
When Porges, a neuroscientist, found so much acceptance among the trauma therapists, he tried to find ways to develop clinical interventions from his theory. He then worked with Deb Dana to develop practical interventions using Polyvagal Theory in therapy, in a way that could be applied to enhance other models of psychotherapy. Even when those interventions exist, they are not considered a therapy modality. They are based on the discovery that prosody, tone of voice, the use of facial expressions make people feel safe, but I find it difficult to faking my facial expressions or tone of voice as an intervention.
Understanding the theory is extremely helpful in treatment but still, there are many therapists that have problems making the shift from the previous understanding. Just by knowing that freeze happens before fight-flight, and that collapse (immobilization) is what comes after fight-flight seems impossible for people to grasp.
For me, the most significant contribution of the Polyvagal theory is the fact that we humans have better (more sophisticated) defenses than other animals, and by using them, we could avoid getting traumatized. Safety in mammals can be achieved by orienting, freeze, and social engagement, instead of relying solely on the fight-flight defense. We are not fighting for our lives all the time as most animals do in the wild. We are responding as such for matters that are really not threatening. We need to use our human brain and the evolved part of us to stay calm and avoid illness.