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The Parasympathetic Nervous System’s Two Branches

Woman holding her headMost people have heard of the two parts of the autonomic nervous system: the sympathetic (promotes a fight-or-flight response) and the parasympathetic (rest and digest state), but many people haven’t heard of the Polyvagal Theory. This theory was proposed by behavior neuroscientist Dr. Stephen Porges.

He views the parasympathetic nervous system as being split into two distinct branches: a ventral vagal system which supports social engagement, and a dorsal vagal system which supports immobilization behaviors, both rest and digest, and defensive shutdown.

The Ventral Vagal Branch

This branch regulates everything and keeps our body calm and in the rest and repair state. It’s also the branch that keeps us socially engaged. When a nervous system is in good shape and is regulated, we’re designed to socially interact with others. We’re a social species, so when we socially interact with others, it gives us good feedback and helps keep that positive feedback going.

The Dorsal Vagal Branch

When this branch is recruited in danger, it creates a shut-down response. This is like what amphibians have, where if they feel in danger, they freeze, stop breathing. and play dead. That’s fine for an amphibian or reptile, as their brain doesn’t use much oxygen. Sometimes they stop breathing for up to an hour as a protection, because then whatever is going to attack them or is dangerous to them will hopefully lose interest and leave.

The value of this part of the nervous system is that if you did fight or run away, there would be more risk to your life than playing dead.

The Role of Chiropractic

With chiropractic, we often pick up on those cues of danger that the nervous system detects subconsciously, from evaluating the tone of the spine and nervous system often before people even notice it. Chiropractic care helps reconnect the brain and body, so you become more aware of your physiology, so you can dial down your nervous system by becoming more ventral vagal.

“What changes your physiology the quickest is the chiropractic adjustment. We offer the quickest effect to allow the body to get more ventral vagal,” said Dr. Don. At our practice, we do that through various measurements: posture measurements, movement measurements, rib cage expansion, and heart rate variability. All those measure objectively how the body is doing.

Discover how chiropractic care can help you maintain a healthy balance between your sympathetic and parasympathetic nervous systems. Schedule an appointment today!

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