Here we go--we're getting to our final few posts in this series. To catch you up to this point:
Part 1: General factsPart 2: Types of tramaPart 3: Aspects of trauma that make it more or less likely to have lingering psychological effectsPart 4: Individual factors that make it more or less likely a person will develop PTSD after a trauma
Part 5 A and B: Developmental trauma (some thoughts on Nobody But Us by Kristin Halbrook) and an interview with Kristin herselfPart 6: Intrusive Recollection
Part 7: Understanding Triggers
Part 8: Avoidance and Numbing

Today we talk about the third and final symptom cluster in PTSD (according to the DSM classification system). The symptoms, according to that manual, are as follows:

Persistent symptoms of increasing arousal (not present before the trauma), indicated by at least two of the following:Difficulty falling or staying asleepIrritability or outbursts of angerDifficulty concentratingHyper-vigilanceExaggerated startle responseRemember what I said in the last post about how our reactions to trauma are about survival? Basically, when we're exposed to a traumatic event, our minds process it in a way that helps us stay alive, and sometimes, that survival mechanism gets a little glitchy. Trauma memories are processed in a different part of the brain than most other memories, and can trigger an instant ALARM. Our bodies respond to that alarm in several ways:
Acceleration of heart and lung actionInhibition of stomach/intestinal actionConstriction of non-vital blood vesselsFreeing of nutrients for muscular actionDilation of blood vessels for muscles
See how those things might help you stay alive? If you're faced with a charging hippopotamus or have to escape a burning building, you might be able to because we're evolved to respond--your body reroutes resources to the essential places while limiting blood flow to other places. And if you're *really* in trouble, your brain might release endorphins that allow you to keep going despite serious injury or intense pain. It's a truly amazing process ... until it gets applied in the wrong situation. Like that veteran I mentioned who was triggered in a public park on a sunny day, simply by a trickle of sweat on his face, and he had a panic attack. Basically, his body switched into survival mode without consulting him, all because of memories processed deep in his brain. 
People who are hyper-aroused are different than when they are not in this state. It's of crucial importance for you to remember that if you're writing this type of character and scene. Here's a diagram adapted from the work of Bruce Perry, MD, PhD, an expert in child trauma (THIS ARTICLE is a helpful must-read!):

You see how someone in a calm, resting state has a clear sense of time and can process abstract thoughts, but as the body kicks into survival mode, she starts to lose that long-term focus. Everything constricts, her sense of time, her ability to reason. Her mind is entirely focused on fighting or running--or freezing. 
Trauma experts talk about how it's not just "fight or flight"--it's "fight or flight or fright." When someone is in an extreme hyperarousal episode, he'll do one of those three things. Most people have a tendency toward one kind of response, though a person who tends toward flight will OFTEN fight if cornered. Women are more likely to engage in flight responses, while men are equally likely to engage in fight or flight. The "fright" response, which you could liken to a possum playing dead, is most often exhibited by young children, youth abused by an adult, youth in an inescapable situation (especially if it involves pain), and girls (twice as likely as boys). 
Now ... for some examples!
A "flight" response:

“One of Coin’s men lays a hand on my arm. It’s not an aggressive move, really, but after the arena, I react defensively to any unfamiliar touch. I jerk my arm free and take off running down the halls. Behind me, there’s the sound of a scuffle, but I don’t stop.” ~ Katniss, from Mockingjay by Suzanne Collins

 A "fight" response (specifically "irritability or outbursts of anger" from the symptom list):

“I felt the violence rising in me with every encounter with the world outside my home. Even inside it I frequently, and with little cause, no cause, boxed Benny’s ears. If I made him squeal and cringe and look at me with eyes gone grave with love and incomprehension, I fancied I felt relief.” ~Tashi, Possessing the Secret of Joy by Alice Walker

A "fright/freeze" response:
Erm. Just read Living Dead Girl by Elizabeth Scott. But be ready when you do--it's intense.

“I hate knowing he’s waiting for me, that he will rub his hands and himself all over me and whisper things. His hands used to make me cry, but now I’m used to them. The thing is, you can get used to anything. You think you can’t, you want to die, but you don’t. You won’t. You just are.” ~ “Alice”, who is being held captive by a predator, Living Dead Girl by Elizabeth Scott

And finally, description of a rage/fight response followed by endorphin release (there's some speculation that those endorphin releases can become addictive, and that traumatized kids sometimes push things in an instinctive need to reach that point):

"Like, whatever I do, there it is, this …rage or …something…that owns my blood and it burns…burns my blood ‘cause it thinks it’s funny or something. I just…" I grit my teeth, shake my head ‘cause this shit ain’t right. "And I get angrier and angrier and then …I gotta do something about it." 

"You can’t hit everything and think that’s going to make it all better." 

"I know that! But it feels good to just…stop fighting it and let it control me. Like …I don’t gotta think none or decide or hold back or nothing.”~Will, who suffered chronic developmental trauma, talking to his girlfriend, Zoe. (Nobody But Us, by Kristin Halbrook)

Ah, there we go. On Friday I'll talk about treatment!