What Happens in the Brain During and After Trauma?

When we think about trauma, we often think about what happened. But trauma is not simply the event itself, it is also what happens inside our brain and body as we attempt to survive it.

Our nervous system is designed to keep us alive. When we encounter danger, the brain rapidly shifts into survival mode. The amygdala, often referred to as the brain's "alarm system," becomes highly active, scanning for threats and triggering a fight, flight, freeze, or fawn response. At the same time, stress hormones such as cortisol and adrenaline surge through the body, preparing us to react.

According to trauma researcher and psychiatrist Bessel van der Kolk, trauma can disrupt the brain's ability to distinguish between past and present. The parts of the brain responsible for reasoning, planning, and perspective-taking become less active, while survival-focused regions take over. This is why individuals may logically know they are safe while their body continues to react as though danger is still present.

Peter Levine, founder of Somatic Experiencing, emphasizes that trauma is not only stored in our memories, it is also held within the nervous system. When a survival response cannot be fully completed, the nervous system may remain stuck in a state of activation or shutdown. This can contribute to symptoms such as anxiety, hypervigilance, emotional numbness, difficulty concentrating, sleep disturbances, and feeling disconnected from oneself or others.

After trauma, the brain often becomes more sensitive to perceived threats. Everyday experiences, sounds, smells, places, or situations can trigger the nervous system to react as though the original danger is happening again. These reactions are not signs of weakness. They are evidence of a nervous system that adapted to survive.

The encouraging news is that the brain and nervous system are capable of healing and oriented towards regulation. Through safe relationships, therapy, mindfulness, body-based interventions, and repeated experiences of safety, the brain can begin to form new pathways (yay for neuroplasticity!).

Over time, the nervous system learns that the threat has passed, allowing the body to return to greater flexibility, connection, and regulation.

Healing from trauma is not about forgetting what happened. It is about helping the brain and body recognize that the danger is no longer occurring and creating space to live more fully in the present.