Stuck in Survival Mode? 4 Ways Trauma Changed Your Brain

Did you know your brain literally changes it's structure and function when you experience trauma? If you've ever felt like you were incapable of escaping a fear and anxiety-driven life, there might be a reason. Hint: It's not because you are defective. Your brain has learned to adapt to trauma, and there are things you can do to help it adapt and grow in a healthy way despite the trauma you've experienced.

When someone experiences trauma, their brain becomes wired for survival, stuck in a heightened state of fear and alertness. Even long after the traumatic event has passed, the brain can continue responding to stress as if it's under immediate threat. Let’s explore how trauma rewires the brain and body, and what we can do to begin healing.

1. A Hyperactive Amygdala: The Brain's Fear Center

The amygdala, the part of the brain responsible for detecting danger, becomes highly alert and sensitive after trauma. It’s like a smoke alarm that goes off with the slightest hint of smoke—even when there’s no fire. The brain, in this fear-driven state, perceives little things as potential threats, even when they aren’t. This makes it harder to tolerate stress, and small triggers can send you into a full-blown threat response, like fight, flight, or freeze.

Over time, the connection between the amygdala and the hippocampus, which helps process emotions and memories, strengthens. Unfortunately, this reinforces the fear response, making it harder to break free from it. Every time a memory or something similar to the trauma pops up, the amygdala sounds the alarm, trapping the brain in a cycle of fear.

Here's what this might look like: you are spending time with your partner over dinner, when all of a sudden they make a facial expression that throws you into complete dysregulation: your heart is beating faster, your face feels red, and you go into panic. You want to jump out of your skin. Your partner's facial expression may have had nothing to do with you and may not have been an attack at all, but your body remembers that facial expression that used to live on your parent's face before the abuse would start. Your body remembers the threat and kicks your survival response into full gear.

2. A Shrunken Hippocampus: Difficulty Distinguishing Past from Present

The hippocampus, which is responsible for processing emotions and memories, shrinks under the constant stress of trauma. This makes it harder for the brain to distinguish between past and present. You may feel like you’re reliving the traumatic event, even though it’s only a memory. When these memories arise, they can re-trigger the amygdala, making the brain react as if the trauma is happening all over again.

Your body and nervous system experience the trigger with the same intensity of the original trauma. It doesn't matter if it happened ten minutes ago or ten years ago. Your nervous system doesn't know time. 

As the hippocampus shrinks, it becomes more difficult to organize memories and emotions. This is why you might feel like you are unable to "move past" your trauma. It's not about you refusing to heal. Your brain needs a chance to re-adapt, but this time to safety.

3. A Disrupted Prefrontal Cortex: Losing the Ability to Think Clearly

The prefrontal cortex, the part of the brain responsible for rational thought and decision-making, also shrinks due to trauma. When the amygdala (emotion center of the brain) is triggered, it shuts down the thinking part of the brain, causing you to revert to survival mode. And this is exactly what it should do when there is a real threat– if a lion is chasing you, you better not sit down and think about what to do. You need to fight back.

When you've experienced trauma, your brain’s ability to reason and use logic is overpowered by the amygdala. This makes it harder to think through traumatic memories, leaving you feeling trapped in the cycle of post-traumatic stress. It's hard to access a thought like, "My partner's facial expression does not mean he is about to hurt me. That facial expression used to be a sign I was about to be hurt, but my partner is not my parent. I am not a young child anymore. I am safe."

Without the prefrontal cortex helping to regulate emotions, it is difficult to override the danger signals coming from the amygdala. The more this cycle is repeated, the more ingrained the fear response becomes, making it harder to manage triggers and flashbacks.

4. A Hyperactive Nervous System: Constantly On Edge

The effects of trauma aren’t limited to the brain. Trauma floods the entire nervous system with stress hormones, locking you into a hyperaroused state where you constantly feel on edge. Do you ever feel like there is a constant vibration occuring beneath your skin? Or do you ever feel like your muscles are constantly tense? This is a sign of a hyperaroused and overburdened nervous system.

Over time, this leads to adrenal fatigue, where the body becomes exhausted from staying in “fight or flight” mode for too long. This chronic state of stress can result in depression, sleep issues, chronic pain, gut problems, and even autoimmune disorders.

When the nervous system is overburdened like this, it’s difficult to feel safe or relaxed. You may find yourself swinging between hyperarousal (feeling overly anxious or on edge) and hypoarousal (feeling numb, disconnected, or exhausted).

Your Brain Can Heal

While trauma has a lasting impact on the brain and body, the good news is that healing is possible. Just as the brain adapted to survive trauma, it can adapt to new, safer environments. By retraining the nervous system, it’s possible to move from a constant state of hyperarousal to a place of calm, where your body and mind can rest and heal.

Healing from trauma often requires a combination of body-based and cognitive approaches. Practices like yoga, mindfulness, and journaling are all ways to help the nervous system shift back into a state of rest and digest, rather than fight or flight. Journaling, in particular, helps rewire the brain by allowing you to process memories in a safe and structured way, helping the prefrontal cortex engage more fully.

Through this work, it’s possible to break the cycle of fear and reactivity, allowing the brain to restore its natural balance. Healing takes time, but with consistent effort, your brain and body can learn how to feel safe again.