Trauma, Our Brain & Regulation

Take aways:

-communication between the three parts of our brain get confused

-need to learn and reflect how each part reacts in various situations 

-use information to identify interventions to reduce trauma symptoms

-begin healing through compassionate awareness  

Trauma can affect anyone of any background and at any point in our lives, with varying individual expressions. Trauma is our emotional response to a terrible event, such as a natural-manmade disaster (i.e. Covid), rape, or an incident (ie. a car crash or domestic violence). What happens to our brain during a trauma is the focus of this blog, along with three ways of helping the body and mind regulate post trauma experience. 



The three parts of our brain


Trauma involves the three parts of our brain: the reptilian, mammalian and neomammalian brains, which are all interconnected. Our first brain, the reptilian brain, composed of the brainstem and cerebellum, is responsible for keeping us alive with our basic functions of breathing, swallowing and regulating our body temperature, digestion, heart rate and blood pressure. It also controls our autonomic nervous responses that we experience as body sensations, such as when we feel relaxed or nervous. We can imagine our reptilian brain like our doctor who is available 24/7 and able to diagnose our sickness. 


When trauma occurs, every activity in the reptilian brain increases with speed, and within milli seconds. Our heart rate rises, our breathing quickens, our muscles tense up and other bodily functions deregulate. All of these signals are then picked up by the second part of our brain, the ‘mammalian brain’ for further processing.  


The mammalian brain, also known as the ’emotional’ or limbic brain, is responsible for many of our executive functions, including which emotions are important and meaningful, keeping us motivated, understanding our social behaviors with and attachment to people, and making sure we learn by storing information in our long-term memory (this part is the last portion of our brain to fully develop, at around age 25). Information coming in from the reptilian brain during trauma gets sorted into three different subparts: the thalamus which is responsible for receiving information from our five senses-sight, sound, smell, touch & taste; the hippocampus which remembers our emotional response and stores it in our longterm memory and lays the foundation for future expectations, including relationship expectations; and the amygdala  which signals us to protect or defend ourselves depending on good or bad feelings. However, the thalamus hijacks the processes of the other two subparts, triggering the hippocampus to pump a lot of cortisol (our stress hormone) and the amygdala to think that we are under attack and must defend ourselves. All three parts simultaneously activate our autonomic nervous system which then triggers our brain to go into alarm/survival mode whereby it only wants to keep us safe and alive. It in fact shuts off other more energy consuming higher level parts of the brain (discussed later). 


In survival mode, the brain responds physiologically in four different ways via one of the (two) autonomic nervous system’s subsystems called, the ‘sympathetic branch’. The responses are: flight-the person runs away from the situation; fight-person uses verbal and/or physical aggression to assert dominance/power; freeze-person is physically, mentally, and emotionally immobilised or numbed out to the point they dissociate from the situation; or fawn-person neutralises the threat/avoids conflict (usually involves a person by pleasing the victim, think of a person staying in a violent relationship). 


On a non-physiological level, our thinking becomes narrow by keeping us small (defenseless), predictable and safe. At the same time, our thinking makes it difficult for us to see possibilities or to be resourceful.  In doing so, we are constantly on alert for perceived danger. Specifically, we are always on the look out for what is wrong, what could go wrong, what to fix or solve, and what is potentially threatening. This can help to explain why we can sometimes, or often, get stuck in loops of negativity, anxiety or feeling stuck. And sometimes for months on end or our entire life.    


When the dust has settled and we begin to pick up the pieces from the trauma, our higher brain, or our ‘neomammalian brain’ comes back online. This brain, also known as the neocortex, cerebral cortex, or the frontal cortex, which sits at the front structure of our brain and split across the left and right hemispheres, is responsible for our creativity, logical thinking and intuition. Post trauma, we often experience feelings of shame and guilt in this brain because it thinks it could have handled the event differently and more successfully if it was in charge. It is worthwhile to note that the rational left hemisphere of this brain matures and develops throughout childhood and into early adulthood, in particular helping with our language abilities and acting as a communication and consolidation bridge between the two hemispheres. So depending on when the trauma occurred, we may have more control/maturity on how we respond to it. Our response can then determine how successful we are at bouncing back, meaning how quickly we can make sense of the issue (ie. not blame ourselves) and move forward with our lives. 


Consequences of unresolved childhood experiences

Development and functioning of all three parts of our brain depend to a large extent on our childhood experiences. These experiences are: our early attachments to caregiver(s) such as our parent(s), grandparent(s), aunt(s), etc, the environmental conditions in which we were being raised in, and the presence and frequency of traumas inflicted upon us. When one of these areas of experience is significantly disturbed, the other experiences may try to compensate in order to bring balance, but they will also be more than likely affected. The degree in differences in our childhood experiences can relegate us back into survival mode at any point in our lives, including in our adulthood, because all parts require consistent repairing through new and meaningful experiences-be it in living in safer environments, having healthier relationships, creating boundaries, to name a few. 


The disturbances may show up in various ways in our lives. For instance, if you grew up with a hypercritical parent who often said, ‘You have loose screws in your head’ every time you were feeling vulnerable and sought advice, you could have developed a fawn response whereby you internalised the parent’s scorn and disappointment in their eyes as you being a burden, unloved, and abandoned, compelling the feeling of numbing out; worse yet, you can develop intense anxiety about yourself and every time someone questions your actions. Another response may be you spacing out (ie not being present/dissociating) during incidents of frightening family abuse. Moreover, many of us end up developing behavioral tendencies, despite their benefits under certain conditions in the form of obsessions and/or compulsions, needing to stay busy all the time, constantly feeling afraid, perfectionism, workaholism, and the inability to sit still. 


In some cases, we can experience something called, ‘complex trauma’, which is the ‘exposure to multiple, often interrelated forms of traumatic experiences AND the difficulties that arise as a result of adapting to or surviving these experiences’ ( When this happens, our brain can also stay stuck in survival mode. 


All of this doesn’t mean we shouldn’t experience any childhood trauma. In fact, it is often argued that adversity helps to define us and builds inner resilience that will later help us successfully navigate this beautiful yet chaotic world. But the degree to how much and what kinds of adversity are inflicted upon us is the looming, nightmare of a question and one that is unique to each of us. And within our life time, many, if not all, of us will have at least two experiences of adversity. I like to compare the childhood adverse trauma reaction to when my computer freezes on me midway during a paper write up and there is only one way to resolve it: to shut the system/computer off. 



Restarting/regulating our system


In order to ‘restart’ our brain, it is important to be aware of how our three brain parts respond in various situations. Remembering that: 1) our neomammalian brain is the thinking brain; 2) the mammalian is our emotional brain; and 3) the reptilian is our survival-body-sensations brain can help us to identify situations in which they may become active. The situations can be both positive and negative, and the experiences can coexist within our brain. The information gained can be later used to help reduce heavy feelings, including that of anxiety or depression which often show up post trauma. 


Once we can understand our brain parts, we can then proceed to getting our thinking brain, in particular, our cerebrum, back online. To start the process we need to be under the guidance of a well trained Trauma Informed Therapist who can help get the body out of survival mode, maintain nervous system regulation, and work with our triggers. Understanding what is happening to us on a physiological level in a trauma response can help us not only have a deeper understanding of ourselves, but also allow for more compassion in our healing journey.


There are a number of ways to work with our nervous system back into regulation. If there is relative regulation in the body, try these 3 steps the next time you notice “survival thinking” (ie: negative thinking, obsessing, ruminating, over-analysing, anxious thoughts, feeling stuck, lost, trapped, not knowing, looping thoughts, can’t see a way out, etc):


When doing this work, always begin by meeting yourself exactly where you are at in the current moment. And start with what feels simple and the most doable for you. Tackling all three steps at once might be too much. And that’s OK! Go at your own pace and slowly invite in the steps a little bit at a time when you are ready. 


Most importantly, give yourself what you need without judgment. Fortunately, our brains are flexible and can repair if we put in the effort to heal. And the more we are aware of what is going on inside of us with compassion and curiousity, the more we can teach our brain to respond in a more constructive and healthy manner in novel situations. In the process, we can significantly reduce, even eliminate, what happened to us and move forward with a renewed sense of self, acceptance, and peace of mind.

Until my next blog, stay well



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