Autonomic Nervous System (ans) With Ptsd

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When the instinctual part of brain (limbic system) perceives danger, it sends messages to your Autonomic Nervous System (ANS). The ANS has two parts, being:

SNS (sympathetic nervous system) is activated with effort & stress, gets the body primed for action; and
PNS (parasympathetic nervous system) is activated in states of rest & relaxation.
SNS & PNS function in balance; generally, when one is activated, the other is suppressed, and this does not go through the logical part of your brain (neocortex).

The following images provide a few different ways of looking at the system, with more discussion below these.




Fight or Flight

During traumatic events, the SNS kicks in and produces a huge adrenalin rush, i.e., survival strategy to mobilise body for fight or flight. The reaction:

Increased breathing & heart rate, more oxygen, blood into big muscles for quick movement,
No oxygen to stomach (nausea) or brain (lightheadedness), and
Fast acting system.
After the danger or enough time, the feedback loop to the brain says, enough adrenalin; PNS then kicks in and relaxation occurs. The chain reaction:

Halts alarm reaction & adrenalin production, restoring restful state, and
Is the slow acting system.

If fight or flight is not possible, or trauma is prolonged, SNS & PNS can be simultaneously activated, causing a state of freezing/tonic immobility (e.g., mouse going dead with cat, rabbit freezing in headlights). The process contains:

System shuts down and trauma victim enters an altered reality,
Heart rate slows down, skin goes pale, as if dead,
Time slows down, no / less intense fear and pain (e.g., people falling from heights or mauled by animals), and
Freezing increases chances of survival & can save life.
An attacker loses interest if the victim appears dead (cat gives up on lifeless mouse, hijacker leaves woman for dead).

Fight, Flight or Freeze?

Fight, flight & freeze are automatic, instinctive survival responses, not thoughtful or considered responses. Which one occurs depends on the limbic system’s perception of the strength and time available. For example:

If time and strength to run away – flee
If no time, but strength – fight
If no time or strength and death imminent – freeze
“If I have a chance to flee I will, if I have a chance to fight I will, if I have to freeze I will”

How this relates to survivor’s guilt or shame for freezing and not protecting themselves, fighting back or running away: What Goes Wrong?

The ANS continues to be chronically aroused even though the threat has passed and is survived. Usual fight / flight response is truncated and the trauma gets “stuck” in the body. Animals don’t get PTSD, for their instinctual “shiver down the spine” allows trauma to be sequenced through their body (wish we had this ability). Survivors’ physiological housekeeping systems are messed up by the trauma. Therapy needs to pay attention to the trauma in the body, i.e., body therapies, mindfulness and grounding.


I always remind myself that freezing up was my defense mechanism at that moment. I shut down to sort of detach from what was going on, and lessen the trauma. It was still bad, but possibly could have been worse. Then again, maybe it wouldn't have been worse. Meh.


Has anyone found any Cranio Sacral therapeutic approach helpful with trauma stored in the body at least? I have read bout CS therapy and Somato-Emotional Release SER in John Upledger's books on the subject. There is a big center in FL for it. I haven't the ability to get it in my area. But if you can get it in your area, I would suggest at least taking a look see into what's available.

The Albatross

I did some Cranio Sacral, and found it to be beneficial... It was a step toward "acknowleging that the crisis event is over" and I learned techniques to do a "self check" of where I am... and I can ground now and put myself back in my body. If that makes sense.

For me, I found I had limited body sensations... or very little at times. I learned how to tell "where I was" when I lay down... and do some breath work and centering now to put myself back in... the self check is back of the head, shoulders, elbows, fore arms and palms to the fingers, the entire spine and legs to the heals. When I can feel all these things I can "recenter" if I feel out of balance or lopsided... and it gives me the opportunity to affirm that the crisis is over and my body is safe now.


... and it gives me the opportunity to affirm that the crisis is over and my body is safe now.

Massage does this for me as well but not as effectively and I don't know how to do it on my own. I'm glad to hear that works for you, and I believe it. I wish someone would come to my area and do this work. I'll keep looking. Thanks!
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