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Conditioned Threat Response

The response of the sympathetic nervous system

This section will look in more detail at the response of the sympathetic nervous system. How a person responds can change. It may be that a person experiences different responses at different times. 

A cat frightened by a large dog.

The Sympathetic Nervous System

Fight or flight response

All animals have the capacity to learn from life threatening experiences. All animals learn to survive through the functions of the areas of the brain that process information through a complex behavioural process that has been termed the fight, flight or freeze response.

The brain’s pathways and behaviours in this response are common to all animals from reptiles to primates. Whether to fight or flee when exposed to a threat must be learnt very quickly through such experiences.

The information from these learning experiences must be stored in the unconscious form in order to be of use in the survival game. It must be capable of triggering a predictable behavioural response learned through trial and error without thinking or planning. The process through which we learn these survival skills is called classical conditioning, a term coined by Pavlov (1926).

All threatening experiences, even those that are successfully resolved, will prompt unconscious responses related to cues from external repetition of the traumatic event.

The ability to initiate the fight, flight or freeze response is determined by the sympathetic nervous system which is one of the two branches of the autonomic nervous system. This sympathetic nervous system is responsible for activating the cardiovascular and motor systems of the body and for making available the extra energy for the vigorous physical activity required to fight or flee.

a pair of legs and the words "restless legs and tension shakes are very common when we are overwhelmed".
  • Image from Trauma is Really Strange by Steve Haines. Copyright Steve Haines 2016, Illustrations copyright Sophie Standing 2016. All rights reserved. This image may not be reproduced or transmitted in any form or by any means, electronic or mechanical including photocopying, recording or by any information and storage retrieval system, without prior written consent from the publisher. Reproduced with the permission of the Licensor through PLSclear.

The Freeze Response

The freeze response is of highly focussed attention and extreme hyper-vigilance in order to judge what the best course of actions is. From an evolutionary perspective, being still was a way for animals to keep themselves safe from predators who rely on movement to catch their prey.

Video

Watch the following video for more information on the fight, flight, freeze response.