trauma and the brain
Trauma, both chronic or severe trauma, can have a significant impact on the brain. It can affect both its structure and function. When we experience a traumatic event, our brain’s fight-or-flight system, also known as the sympathetic nervous system, becomes activated. This activation can trigger the release of stress hormones. For example, our brains can release cortisol or adrenaline - hormones that prepare the body to respond to danger. As an evolutionary response, it is quite brilliant and helpful. And in the moment/ the short term, it can truly be beneficial for survival. However, when trauma is persistent or overwhelming, the brain’s natural recovery mechanisms can become overwhelmed. When this occurs, the brain sometimes remains in its heightened state of stress. This then unfortunately can impair its ability to return to normal operating easily.
One key area of the brain affected by trauma is the hippocampus, which is responsible for our memory formation and emotional regulation. Chronic stress or trauma (acute or complex) can shrink the hippocampus, making it harder for humans to regulate both emotions and also memories in an effective or clear way. This can lead to difficulties with concentration, memory recall, and even an increased risk of developing anxiety or depression. The amygdala, another brain structure, also plays a role in detecting threats and triggering emotional responses. For people who have experienced trauma, the amygdala can become hyperactive. This can then make them more sensitive to perceived threats, even in situations that are not dangerous - a tricky experience to then try to differentiate from.
Additionally, trauma can impact the prefrontal cortex, the brain area responsible for decision-making, impulse control, and judgment. This part of the brain can become less active under prolonged stress, limiting an individual’s ability to think clearly, plan effectively, or control impulsive reactions. This explains why people who have gone through trauma may have difficulty making decisions or may act in ways that seem irrational. The reduced function of the prefrontal cortex also means that emotional regulation becomes harder, which is why trauma survivors may experience intense mood swings or difficulty calming down after feeling upset.
The effects of trauma on the brain can extend beyond just emotional and cognitive issues. Studies have shown that trauma can affect the connectivity between different brain regions. This neurological disruption in communication can result in a decreased ability to integrate different aspects of experience. Over time, this can lead to symptoms such as dissociation or feeling detached from reality. Although trauma and the neurological changes can contribute to ongoing mental health challenges, with the right support, including therapy and stress-reducing techniques, the brain can begin to heal and recover. It is a powerful muscle.
*Citations:
Sapolsky, R. M. (2004). Why Zebras Don't Get Ulcers: The Acclaimed Guide to Stress, Stress-Related Diseases, and Coping. W. H. Freeman.
McEwen, B. S. (2007). Physiology and neurobiology of stress and adaptation: central role of the brain. Physiological Reviews, 87(3), 873–904.
Teicher, M. H., & Samson, J. A. (2016). Childhood maltreatment and psychopathology: A case for the importance of a developmental trauma perspective. In Developmental Psychobiology, 58(6), 714-731.*
