Explaining the ever important “Vagal Brake”

Many times I have talked about the Vagal “brake” but it helps to explain it over. 

Central to regulating our heartrate and thus our regulation of emotional state-change, this phenomenon is important for understanding how chronic stress can sneak up on our physiology. 

Essentially, we are really good at handling stress. Our sympathetic motivations drive us bravely into the world ready to take on challenges.

The vagus slows down the heart into a regulation in the event of a stressor or stimulating event. Think about the brakes on a car to anything that requires systemic arousal: from a social engagement, to a near accident, to a US Presidential debate. This ensures that not only our physiology becomes regular again, but also that we are able to assimilate, fathom, and cope to our emotions.

Emotions are a mammalian adaptive homeostatic response. They evolved to keep us regulated. This vagal brake is then central to this orientation. 

Our reptilian ancestors🦎 , by contrast, only have to “freeze” to respond to stressful environment. They are able to brake the heart for sometimes hours at a time. Humans have four heart chambers and a LOT of evolutionary energetics — such an act would surely kill us instantly. However properties of this freeze response remain embedded in the workings of the vagal bake. When there is an overwhelming event, our hearts can actually “drop” and we can syncope, or faint. 

In order to work in a healthy way, the vagus must operate at an optimal “tone” — just like every nerve in the body aims for an optimal resting tone: maintained by the brainstem. These same brainstem areas relate to respiratory function, tying heart & lung thru respiratory sinus arrhythmia.

Here’s where things get tricky, over time if we are not able to act in healthy ways to work with our rest and recovery processes (sleep/bodywork), our physiology (diet/exercise), or our emotional wellbeing - we actually can diminish the quality of this vagal tone. We risk poorer coping strategies and eventually dysregulation. 

When we understand our physiology first, the better we keep this tone of our body strong. Then we become better at regulating our emotional state-changes.