The doctor told me that the triggers that cause emotional upheaval or physiological distress in patients with PTSD occur because there are memories imbued with high emotional significance stuck in the amygdala. These memories should be processed and put into storage, or long term memory, but they are stuck there because of the emotion associated with them. So when you hit a trigger, or something you associate with that memory, your brain often decides this memory is a current event, due to it’s incorrect location, and dumps all the stress chemicals available to it into your brain/bloodstream. More on those chemicals after this paragraph. So the memory remains fresh, due to it’s location, due to it’s emotional content, which means you avoid thinking about it, and due to the fact that you are avoiding the triggers for it. For if you allowed many triggers into your day, this memory would cease to be associated with them and your brain would not panic at them any longer. The triggers lose importance upon occurring frequently with no ill effects. Rustling grass does not produce a tiger? Brain stops paying attention to rustling grass. Same concept. This is where the desensitization is required in treatment.
That is 120 chemicals, including the cortisol and adrenaline. This is also what happens during panic attacks, this chemical dump. It takes a half hour to burn through these chemicals, which is why my panic attacks always predictably ended. Contrary to how they feel, they will not cause a heart attack, either.
One issue with panic attacks is that they are so unpleasant, that if you feel a little bit like you might have one, you dread one so much that you do panic, and it does end up an attack. So it is a vicious cycle. Luckily, there are time constraints on the frequency as well as the duration. You cannot have more than one in eight hours, if I remember correctly.
If anyone spots an inaccuracy in this information, please comment. This is strictly from memory sans notes, and I am ordering a book on it so that I can get it straight. I will correct any mistakes in factual detail when I have gone through the book.
I am doing this piece by piece, as time allows.