Trauma and the Nervous System

We all fluctuate between states of rest and relaxation and states of our survival response, but how much and how often we spend in our survival response is linked closely with our past experiences and how we interpreted them. The more trauma one has encountered in their life, the more their nervous system has adapted its environmental cues to signify dangerous situations. Your body was just trying to keep you safe and protected, but until you can signify to your nervous system that you are safe now and that past triggers are no longer a threat to your safety, the adaptive responses we'll call trauma will remain embedded in your nervous system's present-day cues.

Some Nervous System Background

Our autonomic nervous system (ANS) regulates the function of our internal physiological processes without conscious effort, such as heart rate, digestion, respiration, and blood pressure. It listens inside to what's happening in and between our internal organs and simultaneously interprets information from our external environment to judge whether we are safe or not. What our ANS deems as a threat from our external environment is often derived from past experiences that have been embedded into our subconscious triggers/judgments (e.g. if you were attacked by a dog as a kid and left with serious injuries it's likely your nervous system will automatically be on alert at the sight of a similar sized dog or even a dog's barking).

There are two branches of the ANS: sympathetic (fight or flight stress response) and parasympathetic ("rest and digest"). When sympathetic pathways are activated, we have a spike of adrenaline and cortisol in our systems and we are no longer focused on our work, hobbies, biological needs (e.g. eating, drinking water, sleep, etc), or connecting with others, but only on resolving the threat at hand.

Our parasympathetic pathways can be divided one step further due to our vagus nerve, which is an integral part of our parasympathetic nervous system. Parasympathetic pathways can be further divided into our Ventral Vagal state and our Dorsal Vagal state. Ventral vagal is our homeostasis state where we feel the most present, at ease, and generally regulated/in control of our life. This is when we're feeling safe and connected with others, focused, curious about our interests, etc. The other state is our dorsal vagal state, which is essentially our immobilization and shut-down state (another survival response). If you've ever felt so overwhelmed by something that you just flop down on the couch and feel like giving up, this is your dorsal vagal shutdown kicking in.

So how are all these pathways related?

Stephen Porges developed Polyvagal Theory which offers insights into the complex interplay between these different pathways. This theory provides a deeper understanding of how our bodies and minds respond to different situations, emphasizing the role of the vagus nerve in shaping our physiological and emotional experiences. Building on the last paragraph:

a. Social Engagement System (Ventral Vagal): When we feel safe and connected, the body activates the parasympathetic branch of the autonomic nervous system, facilitating social engagement, communication, and the ability to connect with others. b. Sympathetic Fight or Flight: In response to potential threats, the sympathetic nervous system triggers the well-known fight or flight response. This is a reactive state where the body prepares for action. c. Dorsal Vagal Freeze: In extreme situations of threat or overwhelm the parasympathetic dorsal vagal branch can lead to a "freeze" response, which involves dissociation, numbness, and disconnection as a survival strategy.

1. Hierarchy of Responses: Polyvagal Theory proposes that these states are organized hierarchically. The social engagement system is the most evolved and effective for dealing with everyday situations. The sympathetic fight or flight response is a secondary response when the social engagement system is insufficient. The dorsal vagal freeze response is the last line of defense and is activated when other responses are inadequate.

Deb Dana, LCSW, a clinician and consultant specializing in using the lens of Polyvagal Theory to understand and resolve the impact of trauma, created the concept of the Polyvagal Ladder to help clients visualize their nervous system hierarchy.

How is this related to trauma?

Even though everyone will experience all three states at countless points in their life, a regulated nervous system will usually have at least one constant foothold in the ventral vagal state. This means that with a bit of intervention from internal resourcing or social support, the regulated nervous system can bounce back from stressful events with relative ease and quickness.

When an individual has a significant traumatic imprint, their ability to judge what is safe or not is impaired and they will end up spending more time in their fight or flight response because they see most things as threatening, or in their shutdown response because they see things as inescapable. To give a few examples, if you were yelled at a lot as a kid, the imprint this leaves on your ANS will often involve an oversensitivity to interpreting people's facial reactions as threatening. This can cause an individual to constantly be operating in their sympathetic response anytime they leave the house. Or, if you were neglected as a child, feeling abandoned in your adult relationships can quickly lead to a persistent dorsal vagal shutdown.

So how do we heal?

With the right care and attention, we can heal our trauma. This is where trauma processing comes in.

So then, what is trauma processing? Read my blog on trauma processing here.