Defense physiology


Defense physiology is a term used to refer to the symphony of body function changes which occur in response to a stress or threat.
When the body executes the "fight-or-flight" reaction or stress response, the nervous system initiates, coordinates and directs specific changes in how the body is functioning, preparing the body to deal with the threat.

Definitions

stress : As it pertains to the term defense physiology, the term stress refers to a perceived threat to the continued functioning of the body / life according to its current state.
threat : What constitutes a threat as it pertains to defense physiology? A threat may be consciously recognized or not. A physical event, a chemical or a biological agent which alters body function away from optimum or healthy functioning may be perceived as a threat .
Life circumstances, though posing no immediate physical danger, could be perceived as a threat. Anything that could change the continuing of the person’s life as they are currently experiencing it could be perceived as a threat.

Physiological reactions to threat (or perceived threat)

A threat may be either empirical or a priori. What is important to the individual, in terms of the body’s response, is that a threat is perceived.
The perception of a threat may also trigger an associated ‘feeling of distress’.
Physiological reactions triggered by mind cannot differentiate both the physical or mental threat separately, Hence the "fight-or-flight" response of mind for the both reactions will be same.

Duration of threat and its different physiological effects on the nervous system.

Acute Stress Reaction - The body executes the “Fight-or-flight” reaction to get the body out of danger quickly. When the timing between the threat and the resolution of the threat are close, the “fight-or-flight" reaction is executed, the threat is handled, and the body returns to its previous state. The body has evolved to stay in this mode for only a short time.
Chronic Stress State - When the timing between the threat and the resolution of the threat are more distant, the “fight-or-flight" reaction continues and becomes the new ‘standard operating condition’ of the body, chronic Defense Physiology. Continuing in this mode produces significant negative effects in many aspects of body functioning.