Stress is the response that occure when we assume we cannot deal with the pressures in our environment.
Pressure/ Demands - Judgement - Yes = deal with demand ( feel little or no stress)
- No = fail to adequeately deal with demand
The evaluation of wether something is a stressor pccurs in the higher brain centers ( cerebal cortex) These higher area send signals to the hypothalumus. This tiny part of the brain makes up for its size by having many functions, including controling the pysiological activites involved with stress. In response to stress the hypothalumus triggers two processes.
Sympathomeduallary Pathway & Pituitary Adrenal System
The initial shock response, the hypotalumus triggers activity in the sympathtic branch of the autonomic nervous system.
The sympathetic branch becomes more active when the body is stressed and using energy.
It stimulates the adrenal medulla within the adrenal gland and releases noraderlanine and adrenaline into the blood stream
This effects the body in several ways :
increase heartbeat etc
This then means that the body is ready to use the energy to deal with the stressfull situation.
Pituitary Adrenal System
If the stress is long term then the symathmeduallary process wil start to use up the body's resources . So a second system produces countershock response- which supplies your body with more fuel.
The hypothalumus triggers the release of CRH.
CRH stimulates the anterior pituitary gland this then release a hormone called ACTH.
ACTH travels through the body to the adrenal cortex.
The adrenal cortex releses corticosteroids to convert protein and fat into energy.