The Science of Trauma
This post is a more in depth look at how our brains and bodies respond to traumatic experiences. It’s an area of research called interpersonal neurobiology, which explores how human experiences can be understood when bringing together different fields of study such as neuroscience, biology and psychology. It was started by Dan Siegel. I also use the works of Stephen Porges, who is the founder of Traumatic Stress Research Consortium, and Bessel Van der Kolk who’s works have explored traumatic reactions through the lenses of attachment and neuroscience.
If you’re interested in this area I encourage you to explore their published works. This area is essential for professions working within trauma to understand so they can offer trauma-informed responses. It’s also useful for anyone working within education or caring roles as you will come across people who have experienced trauma.
As it’s a huge area I’ve split it up into a series of posts. The first part will be about the fundamentals of the human brain.
The Brain
The human brain is, understatement coming, very complex. An adult brain has about 100 billion neurons. These neurons connect , forming a pathway, to each other to pass on messages. The more a pathway is used the stronger it gets. Think of going for a walk on a field- the more a path is walked the more trampled the grass gets until it forms a pathway. The stronger the pathway is in the brain, the harder it is to break. Trauma has the ability to suddenly break pathways and changing how the brain wires itself. So part of trauma therapy involves understanding this and helping a person to change some of the wiring back (this is called neuroplasticity).
Our brain can be thought of as having three main areas. These areas don’t work independently but have lots of connections (pathways) to each other. This is especially true of the pathway between the limbic system and the neocortex.
Image credit: istock
Reptilian Brain: This is the oldest bit of the brain (in terms of evolution). It covers essential processes for regulating heart rate, breathing, eating, body temperature, balance and motor skills, consciousness and the sleep cycle.
Mammalian Brain: This area of the brain is sometimes known as the ‘emotional brain’ because it is the limbic system. The limbic system has several very important area in it including the amygdala, hippocampus and the hypothalamus. Jaak Panksepp, a neuroscientist, mapped out seven emotional nextworks in our brains: SEEKING, RAGE, FEAR, LUST, CARE, PANIC/GRIEF, and PLAY. His research states that all emotions can be linked back to these networks. These emotional nextworks are all found within the limbic system. You can read more about it in his book Affective Neuroscience. I’ll come back to the limbic system in a later blog post
Neocortex: The neocortex is a name for a large number of areas of higher brain processes. It’s important for things like perception, reasoning and language. The neocortex is home to our four frontal lobes. These are the bits not properly developed in babies when they’re born. They develop through positive interactions with care givers. The frontal lobes are not considered ‘fully formed’ until the age of 25. They are important for things such as managing stress, problem solving, impulse control, concentration and social intelligence (which includes empathy).
So, why is this all important? Well MRIs show that parts of our brains ‘light up’ when they are being used doing different tasks. So not all of our brain areas are working when we’re doing different tasks. For example, if you’re climbing a tree the reptilian brain will be hard at work because it has the cerebellum in it, which is responsible for balancing and motor-coordination.
How is that linked to trauma? Well trauma impacts the limbic system in our brains a lot. When that happens other bits of our brains aren’t used as much- especially the frontal lobes. This is why we often see people who are suffering with traumatic stress having issues with concentration and problem solving as well as other areas; their brains are more often working in areas of the limbic system instead.
In my next post I’ll explore the limbic system in more detail and how it responds to trauma.