The Polyvagal Theory Ladder

We tend to think we’re completely in control of ourselves, but there’s a lot happening physiologically that we aren’t aware of. How do we adjust any of our reactions or behaviors if we aren’t even aware of them?

The polyvagal theory helps us recognize and understand the parts of these unconscious systems that we need to work on. It was developed by Dr. Stephen Porges in the 90s when he identified certain nuances in human behavior.

The Polyvagal Theory Ladder

The polyvagal theory ladder puts the fight and flight, freeze, and social engagement responses on a ladder that we move up and down. 

We move up and down the rungs of the ladder depending on what’s happening to us. Ideally, we live most of the time at the top rung of the social engagement system. 

Everyone will experience extreme stress responses from time to time. However, constantly living with those responses isn’t just tiring, it can cause lasting effects.

Safe and Social

The top of the ladder lies our social engagement system. It’s controlled by the ventral vagus nerve circuit. This is how we usually act, and usually how we want to act—aware, but at ease.

Mobilization

In the middle of the ladder lies our sympathetic nervous system. This is our fight or flight mode. This is a useful place for us to be when we are in danger. But existing on this wrung for an extended period causes anxiety and trauma.

Shutdown

At the bottom of the ladder lies our parasympathetic nervous system. This is our freeze or immobilization response to danger. It’s controlled by the dorsal vagus nerve. An overactive freeze response causes people to stay on this bottom wrung. According to polyvagal theory, this part of the ladder leads to depression.

The Old Model: A Two Part Nervous System 

The autonomic nervous system controls our involuntary physiological processes such as breathing, digestion, and heart rate. Before the polyvagal  theory, the autonomic nervous system was thought of as being made up of only two parts: 

• Sympathetic 
• Parasympathetic 

We’ve also classified these parts as “antagonistic,” meaning they have opposite functions.

Sympathetic Nervous System

The sympathetic nervous system controls our response to danger. It is the part of the nervous system that takes action when we feel threatened.

This part of our nervous system makes our body do all the unconscious things that help us escape danger:

• Increasing heart rate
• Increasing or decreasing blood to specific parts of the body
• Heightens senses 

The sympathetic nervous system is our fight or flight response.

Parasympathetic Nervous System

The parasympathetic nervous system dictates our “normal” bodily functions when we’re relaxed and at rest. It dictates your resting heart rate, produces saliva, controls how pupils respond to light, and digestion. 

This is our “rest and digest” or “feed and breed” state. After danger has passed, your parasympathetic nervous system kicks in to bring everything back to normal levels. The vagus nerve makes up about 75% of the parasympathetic nervous system.

The Social Engagement System

Porges hypothesized that there is a third part of our autonomic nervous system besides “default rest” and “fighting for our lives.” He called this the social engagement system and it's controlled by the vagus nerve. 

Porges used this to explain a bodily state when we’re on alert, but not in the "looking out for danger" way. Rather it describes the level of alertness you need in social interactions or at work.

We’re stimulated, but we’re playful, motivated, and energized. It’s a state where we’re relaxed, but we still perceive our surroundings.

When the vagus nerve is working to stop the sympathetic response, it engages the social engagement system. This system is considered the go-between of the sympathetic and parasympathetic responses.

Trauma Disrupting the Social Engagement System

Traumatic experiences, especially complex trauma, cause us to have over-stimulated sympathetic or parasympathetic responses. It can cause us to feel anxious (sympathetic) or shut-down (parasympathetic) most of the time, or when innappropriate. When this happens, we have trouble accessing the social engagement system. 

Neuroception is the process of subconsciously scanning for danger or perceptions of it. Trauma can cause people to constantly scan for danger, such as in cases of posttraumatic stress disorder. Triggers cause people to disengage from the social engagement system in order to enter fight or flight mode. 

A trauma response is an involuntary response of the nervous system that sends your body into physical action or inaction. Addressing the way your body reacts during a trauma response is an effective way to lessen its impact and take away its power. 

How the Polyvagal Ladder Helps Us

The polyvagal ladder helps us regulate our emotional responses. There aren’t just two extremes, but a happy medium where people can exist happily. Knowing about the possible states of reactivity can help put things into perspective. It allows us to realize that dropping down the ladder is not permanent and we can climb back up. 

Sometimes the states become mixed. For example, playing a sport could put you in a social and safe, and fight or flight state at the same time. Mediation could put you in the shutdown and social engagement states. 

Trauma can cause us to be unable to reach different rungs on the ladder. Somatic experiencing can help you access each state when appropriate.

Trauma Therapy at Sequoia

At Sequoia Behavioral Health, we use somatic experiencing to help clients access the parts of their nervous system that have been injured from trauma. We have certified practitioners with knowledge and experience in providing quality and individualized care.

‍Reach out today to have more control over your tomorrow.