POLYVAGAL THEORY & THE NERVOUS SYSTEM

The Polyvagal Theory is a theory of the autonomic nervous system (ANS) that was proposed by Stephen Porges in the early 1990s. The theory states that the ANS is composed of three distinct neural circuits: the ventral vagal circuit, the sympathetic nervous system (SNS), and the dorsal vagal circuit. Each of these circuits is responsible for different aspects of the body's response to stress and danger.

The ventral vagal circuit is responsible for the body's "rest and digest" response. This circuit is activated when the body is safe and relaxed. When the ventral vagal circuit is activated, the heart rate slows, blood pressure decreases, and the digestive system is able to function properly.

The sympathetic nervous system is responsible for the body's "fight or flight" response. This circuit is activated when the body is under stress or in danger. When the sympathetic nervous system is activated, the heart rate increases, blood pressure rises, and the body's muscles are primed for action.

The dorsal vagal circuit is responsible for the body's "freeze" response. This circuit is activated when the body is overwhelmed by stress or danger. When the dorsal vagal circuit is activated, the heart rate and blood pressure drop dramatically, and the body's muscles tense up in order to protect itself.

Polyvagal Theory has important implications for our understanding of stress, anxiety, and trauma. The theory suggests that the different neural circuits that make up the ANS are constantly interacting with each other, and that the balance between these circuits is crucial for maintaining mental and physical health. When one of these circuits is over-activated, it can lead to problems such as anxiety, stress, and trauma.

Solutions that focus on activating the ventral vagal circuit (such as yoga and meditation) can be helpful for treating conditions like anxiety and stress. Therapies that focus on activating the sympathetic nervous system (such as exposure therapy) can be helpful for treating conditions like PTSD. Polyvagal Theory therefore provides a framework for understanding how different approaches can be used to treat problems with the ANS.