I'm an ignorant person here, although I think I still have some common sense left. I scanned through these posts here... too in-depth and long to follow. I did however take notice to the MRI pics. This group has a smaller part of the brain then that group; Normal vs PTSD. I want to see before and after of the same person. Maybe having a smaller than average hippocampus predisposes someone to breaking down after experiencing trauma in their life- that can be concluded... maybe it does shrink due to excessive stress, but that it shrinks due to PTSD specifically- that cannot be proven IMHO.

"Exciting recent research has shown that the hippocampus has the capacity to regenerate nerve cells ("neurons") as part of its normal functioning, and that stress impairs that functioning by stopping or slowing down neuron regeneration.19,20"

Like I said earlier, how can the finger be pointed to PTSD specifically? And, to tell me that stress impairs something neurologically or macroscopically is old news... no Nobel Prize yet.