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  • Agnes Wohl

How Does Psychological Trauma Affect the Brain?

Updated: Nov 8, 2021

According to the Mayo Clinic, the most common events that lead to PTSD include:

  • Combat exposure

  • Childhood physical abuse

  • Sexual violence

  • Physical assault

  • Being threatened by a weapon

  • Being in an accident

  • Medical trauma

How does psychological trauma affect the brain?

There are three areas of the brain that are involved in the response to psychological trauma. The amygdala, the hippocampus, and the prefrontal cortex. Each of these areas serves different functions. The amygdala is the brain area that controls our “fight or flight” response to events. It is believed to be the area of the brain that processes fearful and threatening stimuli.

The hippocampus is the area of the brain responsible for learning and memory. Unfortunately, the hippocampus is also known to be a vulnerable structure easily damaged by various stimuli, most notably trauma.

The prefrontal cortex is an area of the brain that receives input from other regions of the brain and plays a central role in cognitive control functions and influences attention, impulse inhibition, memory, and other executive functions.

People who suffer from psychological trauma and PTSD have an amygdala that becomes hyperactive. The amygdala is the alarm system in the brain. It tells the brain to release hormones, which put the body into hyperalert. In turn, this leads to increased fear, stress, and irritation. This hyperactivity often leads to the inability to calm down and can even impact their sleep.

As we said, the hippocampus is a vulnerable area of the brain that can be easily damaged. Studies have shown that people who have PTSD have a smaller hippocampus compared to the average. As the hippocampus controls memories, the loss of volume can affect the ability to recall some memories while causing other memories to be quite vivid, acting as a constant reminder of the traumatic events. With these memories constantly on the victim’s mind, the slightest event can cause the memory to activate the flight or fight fear response in the amygdala. The victim can often not differentiate between the memory and the actual event from the past.

It is the job of the prefrontal cortex to take all of the inputs from the hippocampus and amygdala, control those inputs and allow a person to react rationally, putting the memories in proper perspective. However, in people who have PTSD, the information from the other parts of the brain overwhelms the prefrontal cortex. As a result, it becomes extremely difficult to regulate and control the fear associated with the memory.

How does psychological trauma affect the nervous system?

As we have seen, people who have PTSD suffer from physical changes in the brain that impact how different brain areas work. The reduced volume of the hippocampus works with the hyperactive amygdala to overpower the prefrontal cortex.

The overstimulated amygdala also directly impacts the nervous system, overstimulating it to the point that we lose the ability to regulate it. The nervous system is then stuck in this overstimulated state, causing an inability to relax, increased anxiety, higher levels of anger, panic, and reactivity.

On the opposite end of the spectrum is hypoactivity. Victims may also experience a state where the nervous system is effectively turned off, leading to depression, the feeling of being disconnected from others and themselves and they may experience high levels of fatigue, and lethargy. People may experience one or the other or even vacillate between the two extreme states.

There is Hope

Our brain is an amazing organ, capable of change. It can create new neural networks to replace the old, less functional ones. It is constantly changing and working to regulate itself. However, healing from psychological trauma is possible. It may not be easy and requires effort, but it is possible to overcome the trauma and PTSD to live your best possible life. We can take many avenues to work through the trauma that you have experienced, even as a child. Recovery is a journey, and you can emerge from the darkness and once again be happy and healthy.

Treatments including EMDR, Sensorimotor Psychotherapy and Somatic Experience Therapy help to reset the nervous system. Stay tuned to learn more about these therapies.

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