How does PTSD affect the brain? If you want to recover, it’s important that you know the basics.

Post-Traumatic Stress Disorder (PTSD) is a serious mental health condition that can occur when you experience or witness a horrific event. It causes extreme anxiety, intrusive thoughts like flashbacks, and so much more. PTSD does this by affecting and altering your brain function. Understanding how this process works is an important part of recovery.

Put simply, your body is equipped with a built-in alarm system. When all is running properly, it does an incredible job of protecting you. Under the influence of PTSD, however, this alarm system short circuits. You lose the ability to differentiate between typical events and the traumatic event you experienced.

3 Key Ways PTSD Affects the Brain

In the face of a crisis, the brain is ideally suited to prepare and protect you. As a result, your sympathetic nervous system puts you into survival mode. When the danger has passed, you return to a normal state and move on. That switch does not happen for people with PTSD. This can be best understood by examining how PTSD affects three key parts of the brain.


For some, as big as an almond, the amygdala has a huge influence on your behavior. It’s the part of your brain that, at the first hint of danger, launches you into fight-or-flight mode. However, when you have been through trauma and have not processed it, the amygdala will literally grow in size and power. It takes the protective role to the point where it can no longer tell the difference between what’s happening now and what you went through in the past.

For example, if you hear a sound that reminds you of the traumatic event, the amygdala will start releasing stress hormones to handle the risky situation. In other words, you’re stuck in a state of high alert.


This part of the brain is responsible for storing memories — including emotional memories. It helps us learn about what is and isn’t safe. In the presence of trauma, the hippocampus sees its duties overridden by the amygdala.

As the amygdala grows, the hippocampus shrinks. No longer can the hippocampus modulate the amygdala’s responses. Without such a checkpoint, the past and present are blurred into one as you move into feeling chronic hypervigilance.

how does ptsd affect the brainPrefrontal Cortex

Finally, we have the prefrontal cortex (PFC). It is designed to help you make rational decisions based on verifiable evidence. In the brains of trauma survivors, the PFC is consistently found to be less active.

As is the case with the hippocampus, the PFC is overwhelmed by an amygdala running wild. Lacking the valuable skills of rational thinking, there is virtually nothing left to counter the claims of the amygdala that you are under constant threat. With each passing experience, this cycle gets more deeply embedded.

Where Does This Leave You?

For starters, your tolerance decreases in a major way. Imagine your nervous system always operating in overdrive. This naturally reduces the threshold of how much stress it takes to set off your fight-or-flight response. Eventually, it takes very little to leave you feeling like you are reliving the original event. Until you get treatment and resolve the trauma, you are at risk of nightmares, flashbacks, and other debilitating symptoms.

The Next Big Step

Now that you have an idea of what PTSD is and how it affects your brain, the next step is yours. Effective treatment options are available and recovery is absolutely possible. It all begins with a phone call. Reach out to set up a free and confidential consultation for trauma therapy. Get your questions answered and learn all about how you can thrive once again. I look forward to working with you.