Chances are that you learned about the Autonomic Nervous System in science class many years ago. So, let’s clear those cobwebs with a quick refresher on what it is and how understanding it can help you.
Your Nervous System is always scanning the environment to detect threats. This risk assessment is known as “Neuroception.” When you learn to read your body sensations that arise with feelings of threat or safety, you are better able to communicate your needs.
The Autonomic Nervous System (ANS) is the part of the Nervous System that regulates and controls involuntary internal organs functions such as controlling blood pressure, heart rate, respiration and digestion. Traditionally we were taught that the ANS is divided into two main parts:
SNS Sympathetic Nervous System (Fight or Flight)
PSNS Parasympathetic (Rest and Digest)
The antagonistic systems balance between action and rest. The Sympathetic Nervous System collections information from the internal organs and sends them to the brain mostly through the spinal cord. The Parasympathetic Nervous System shares information to and from the brain and the internal organs through the Vagus Nerve.
PSNS is the relaxing component of the Nervous System which balances out the active SNS. For example, when you jump and yell, an unconscious reaction of the Sympathetic Nervous System, because you mistook a rope on the ground as a snake, it is your PSNS that signals the body to lower the heart rate once you realize that you are safe. When the SNS is activated the PSNS and its functions are put on the back-burner and vice-versa. The SNS response at its extreme is mobilization. The PSNS at its extreme presents as “shut-down” or “Freeze” response. So how can we explain everyday interactions where we are not at either end of the spectrum? It turns out that there is another part of the PSNS that we had been missing.
The Polyvagal Theory, based on the work of Stephen Porges, proposes that there is a more nuanced system than the binary activation or “shut-down” responses. He suggests that there is a third response called “The Social Engagement System.” This system is a mixture of activation and calming.
Porges theorizes that there are three states of Nervous System Activation:
Ventral Vagal Social Engagement
Dorsal Vagal Shut-Down
“Poly” means many and “Vagal” refers to the Vagus Nerve. The Dorsal Vagal and Ventral Vagal are two different parts of the Parasympathetic Nervous System. Remember that the Vagus Nerve is the PSNS’s main pathway for the nerves of the internal organs to share information to and from the brain. Dorsal means posterior or back and Ventral means anterior or front.
The organs located above your heart, including most of your facial muscles are controlled by the front pathways of the Vagus Nerve, the Ventral Vagal. When you are in the Ventral Vagal Social Engagement State you are able to connect with others, express and read facial expression, listen to the words of the person in front of you, keep eye contact and display signs of connection to those around you. You are able to be in this state when your Nervous System scans and determines that you are safe.
The next state is Sympathetic Activation. This is the default mode for anytime that you are under stress. You may feel the need to pace the room or even run away or maybe you feel ready for confrontation or a physical fight. Your system prepares you to take action against whatever threat you are facing. Since the main nerves involved in transmitting information from your organs to your brain are located in the front of your spine, chronic stress can result in tense muscles in your back.
The Dorsal Vagal Pathways run on the backside of the Vagus Nerve. The organs located below your diaphragm, the muscle right below your lungs, are mostly controlled by Dorsal Vagal Shut-down. The Dorsal Vagal and Ventral Vagal share regulation of the heart and lungs.
The Dorsal Vagal pathways were developed first. This pathway can be found in retiles and explains why many retiles freeze when under threat instead of fleeing. This is their primary defense mechanism. As mammals evolved, we developed the Sympathetic Activation Response as a new defense technique to better survive predators. Ventral Vagal Social Engagement is the most recent part of the mammalian Nervous System. This allows mammals to connect and cooperate for better chances of survival.
Dorsal Ventral Shut-down is a very primal response and for people, it can be damaging if it becomes the main response to threat. In this state the heart rate lowers, the breath becomes shallow and oxygen levels lower. When someone faints, this is the Dorsal Ventral Shut-down at play. Generally humans use this response as a last resort when attempts of connection have failed and they are unable to fight or flee. Passengers of a car accident may use this response, while the driver might remain in Sympathetic Activation, as they have some semblance of control in the situation and they can attempt to steer. Dorsal Ventral response is common for children in abusive households. Since they are unable to flee their caregivers some of them find that the best option is to dissociate in order to survive. Many who have been sexually harassed or overpowered by another will also turn to this response if there is fear that fighting back will result in greater danger.
Have you ever heard the phrase “neurons that fire together wire together”? In this case, every time you resort to the primal Dorsal Vagal Shut-down mode, the pathways become stronger and stronger, making it more likely to become your go-to response. Think about walking through a heavy snow. The first path you make is laborsome. You could change course at any time and the effort would be the same. However, each subsequent walk would be easier if you were to follow your previous footprints. Eventually, you don’t think about taking other paths. When in Dorsal Ventral Shut-down the possibility for Social Engagement is impossible. The pathways in your brain are not available. You have to slowly move into Sympathetic Activation and then to Ventral Vagal Social Engagement.
Imagine a child who freezes because they have been yelled at. Their parent might be trying to talk to them to understand their actions, but the child looks at them dead eyed and shoulders rounded. The parent becomes more frustrated and continues yelling, keeping the child in the shut-down state. Before the child can move up to Sympathetic Activation they need to receive cues of safety, for example a soothing voice or slow and steady breathing from the adult reprimanding them. Only once the child is out of the shut-down state can a conversation occur with the possibility of connection and understanding.
By Understanding your go-to state when under stress or threat you can better catch yourself from reacting at one extreme end or the other. For example, there is a couple where the female partner tended to go into a shut-down response under threat and the male tended towards Sympathetic Activation. Whenever they had disagreements the male would pace the room with fists closed and talk in a raised voice as an unconscious way to discharge the Sympathetic Activation. The female’s Nervous System read those signs as aggression and went into shut-down, she sat on a chair, avoided eye contact and tried to wait out the argument. Both Nervous Systems were signaling each other without the conscious awareness of the couple. The male took the avoidance as indifference which fueled his fight response even more. Once the couple learned about their tendencies, the male realized that when he started pacing he was sending threatening signals to his partner. He chose to take a walk instead and then pick up the conversation when he could sit down and speak with a lowered voice. The female worked on eye contact and asking for a pause to stand up, go outside or just move around when the conversation began to get too heated.
As you learn more about your tendencies, you can get better at responding consciously instead of reacting subconsciously. With awareness comes the opportunity to have a better understanding of yourself and healthier relationships with others. If you are interested in delving deeper into the Polyvagal Theory, please check out some of the videos and articles below.
Stephen Porges Website
Polyvagal Map Video
Polyvagal Explained Simply Video
Understanding Why you are Who you are interview with Dr. Stephen Porges
The New Science of Safety and Trauma Video
Polyvagal Theory in Practice