Introduction to the Triune Brain: stress and trauma
In this article:
– What is the triune brain?
– How do the 3 distinct parts of the triune brain react to stress/danger?
– The triune brain and trauma
– How Conscious Connected breathwork heals the nervous system
The human nervous system is the result of millions of years of evolution. We were once reptiles, then mammals, then humans. This 3-stage process of becoming human is evident in the triune brain theory by Paul McLean. The triune brain refers to 3 distinct systems of the brain that are built upon one another. If you refer to the photo below, our innermost brain (shown in red) is our reptilian brain, it is the part of our brain and nervous system that we share with reptiles, this part of the brain that functions on survival instincts and coordinates breathing, swallowing, and heartbeat among other vital functions. The higher order limbic system (shown in yellow) is found in mammals and is responsible for most aspects of emotions. The final brain system to be developed is known as the neocortex and it is most developed in humans and is associated with higher order thought, such as planning, language, and logic.

Most of the time that a human is in a safe environment it will operate on all levels of our brain with the greatest emphasis on the neocortex. However, in the event of extreme stress or danger our reptilian brain will become predominately active. What this means is that if a bear leaps out at you your neocortex will shut down the blood flow and the resources needed for logical reasoning and the resources will move towards the more survival orientated limbic and reptilian aspects of the brain.
Let’s examine this a bit closer…
-incident: a bear crosses your path in the woods
– The neocortex shuts down, reptilian brain activates the fight or flight survival response, which is a survival system in the body that activates the autonomic nervous system preparing the body for action, in this case pupils will dilate to let in more light, adrenaline and cortisol – the two primary stress molecules will be released, heart rate will increase and blood vessels will constrict to shunt more blood to the muscles for movements, the bowels and urinary bladder may void to allow for faster running, and bronchioles of the lungs will dilate to allow for oxygen in order to flight or flee.
– the limbic system will activate several regions, 2 major one’s being the amygdala which makes a snap judgements about safety and acts to set off alarms to activate the emotion fear and release additional stress hormones, and the hippocampus which plays a major role in memory formation. In this case the amygdala, it will become activate leading to cascades of hormonal secretions to alert the body for action, and the hippocampus will become hyperactive recording everything in the environment, in case the situation is ever encountered in the future the brain will have a log of memories.
After the incident with the bear proves to be nothing more than a scare, the nervous system, so long as it deems it is safe, will de-activate the stress response, the body will be brought back into homeostasis (balance) and the neocortex will come back online.
Ideally that is how things work, yet in today’s world the majority of stress we encounter is not via predatory animals, but a mixture of lower level chronic stress, and larger issue’s like financial stress which bear a continuous burden and continuous stress response affecting all systems of the body.
Tip #1: Be aware of your body, the more in tune you are with your nervous system, the more sensitive you will be to changes in heart rate, sweating, drying of saliva, increased need to urinate, increased breathing or holding of the breath, etc…which are all signs that your autonomic nervous system is activating your stress response. If you’re at work at your notice these symptoms there are measures you can take to calm your nervous system down such as deep diaphragm breathing, going for a walk, using the box breathing app, etc. But if your unaware you are stressed as you stressed, the system will continue to pump out adrenaline and cortisol stimulating your body, deactivating your immune system, and other deleterious effects is sustained.
If our stress systems is chronically activated it will first activates the autonomic nervous system as described above, then it will start to affect the limbic system blunting one’s ability to feel emotions and engage in loving relationships, and eventually the stress will deteriorate one’s ability to do cognitive tasks and learn new information.
The triune brain and trauma
In another example, a young woman has been sexually abused from a male 5 years ago and has not wholly integrated and healed from the experience. At the time of the incident her reptilian brain is activated, releasing stress hormones, she may even drop into a freeze state of frozen rigidity as witnessed in some reptiles and mammals under extreme conditions. On the level of her limbic brain, her amygdala and hippocampus will be hyperactive recording all the memories, cues, and activating hormonal stress cascades. In this case, after the event is over there was a failure for a completion, in which the nervous system and the person involved can come back to balance and come back to feeling safe. The nervous system is essentially still under stress, unable to bring itself back into homeostasis, believing the danger is not over. There is often an element of dissociation that occurs as a person experiences trauma to create some distance from themselves and their pain which at the time was too overwhelming. What at the time was an appropriate reaction, becomes a continued source of struggle as a part of this girl is frozen in trauma. This will cause a chronic stress response in the nervous system. Areas such as the amygdala will be constantly looking for threats, chronic activation of the amygdala can result in depression, anxiety, and hypothalamic-pituitary-adrenal axis dysregulation. The brain will be wired on threat detection mode, it will be searching for cues and remain on high alert, any male or event similar may re-activate that response in the nervous system to protect itself from harm. As this state becomes chronic the person’s ability to feel emotions (limbic system) and openly give and receive love can be affected, they may develop a generalized dislike of males, and later even their cognitive abilities (neocortex) can become affected.
Key components of trauma release through conscious connected breathing
Before we get into the technique of Conscious Connected Breathwork and how it can help our young woman from the above example, there are some important qualities of the environment in which healing should ideally take place. Creating a safe space for healing is essential for a person to relax and move into difficult emotions. We are mammals, and all mammals share is a similar trauma cycle and building up of emotions and energy during trauma. In the wild, if a mammal survives a predator attack by fleeing, they will find a safe space to lie down, and release this pent up charge of energy in the form of twitching and convulsing which allows for a completion of the event, and restores the nervous system to balance, time stamping the event as happening in the past. So too in humans it is essential that a safe space is created, including not only the physical environment, but the safety of the container, which is maintained by the facilitator and other people involved.
I won’t give a detailed description of Conscious Connected Breathing here, for our present purposes the important points are that an individual is lying down and conscious connecting their inhale and exhale continuously throughout the session. Our bodies store memories and emotions of the past, and as one breaths in the specific method of conscious connected breathing, individuals have a natural response to opening up pockets of holding in their body wherein stored emotions and memories are stored and may be evoked.
For example, the women who was a victim of sexual abuse in our above example may move into some of the emotions and sensations involved in her traumatic experience. With a trained facilitator she will be invited to continue her breath, remaining a witness of any emotions, sensations, and staying connected. Through this process, with guidance, and the support of the facilitator and perhaps the group, an individual, now resourced with strength and the curiosity to move bravely through the emotions can fully step into the messages still stored in the body and allow for a completion of the event. Everyone’s experience is different, some evoke stories and images, or mere sensations and movements of energy. As she is able to move fully into the emotion it is released.
In order to heal it we must feel it.
As she becomes complete with her emotional piece the nervous system finally says “ah, I am safe”, and it floods the body with relaxing chemicals and hormones to signify the event is over. There is a drop in stress hormones, and there will be a resolution of trapped energy, often in the diaphragm resulting in a deeper more full breath pattern. As the nervous system becomes complete it time stamps the event as in the past, and the chronically activated areas that were causing a plethora of negative symptoms release restoring homeostasis in the body. This can change several aspects of a person’s experience, for example, when the body is chronically stressed it stimulated the sympathetic division of the autonomic nervous system which prepares the body for action and creates a kind of tunnel vision to aid in concentration of fighting or fleeing. Thus, in the experience of trauma release and the activation of the parasympathetic system there can often be a widen of the vision system.
Additional notes of healing
The words health, healing, whole, and holy all come from the same root. Which denotes the relationship between becoming whole through integrating all aspects of ourselves we once lost due to dissociation and trauma. It also points to a larger idea, that we do not heal for ourselves, but for the betterment of all people and beings. There is a recognition in the work in trauma healing that we heal not only for ourselves, our community but also for our planet. All aspects are necessary, without the support of mother earth and community, there is no safe space with which to gather. There is no way to live but in harmony with our planet. I lift up all the brave souls courageously going into their own pain, for if we don’t, we would all be stuck in survival mode. when we heal, we open the doors to greater levels of emotion, love, that make the higher order human endeavours of art and science possible. We let go of pain, and allow new qualities to be invited in.
Deep gratitude to the earth, deep gratitude to the community, and deep gratitude to all beings.