Now that we know how to define PTSD and the symptoms, let’s talk about what causes PTSD. We’re going to get technical for a minute, so hang on with me.
As humans, we are born with built-in alarms systems to alert us to danger so we can either “fight or flee.” That alarm system, which is commonly called the “limbic system” or the “arousal system”, is vital to our survival.
When activated by stress, the alarm system prepares you to fight off an attack or to flee (escape), which means your heart rate and breathing rate increase, muscles tense, adrenaline rushes, etc. Our alarm system does not know time or location; it only recognizes danger and the feeling of threat. It simply fires up and keeps you in an aroused state so that you can be prepared in the face of perceived or imminent threat.
When the danger is over, the alarm system is supposed to shut down, allowing the body to relax and return to normal. However, traumatic events can impair the functioning of the alarm system so that you cannot tell when the danger is over and your alarm system does not shut down properly. You continue to feel as if the danger is ever present, which promotes a state of chronic hyperarousal.
When vets were deployed, their alarm system was constantly on, alerting them to the fact that they were always in a state of danger. It over generalizes so that it does not miss any threats to your survival.
But here is where this treatment focus begins. Your alarm system worked perfectly well when you were deployed because you actually were in danger all the time, and needed to be alert all the time. But now that you are home, your alarm system has stayed on even when there is no actual threat of danger.