Bethany PostleQ: Explain how the SAM and HPA system workA: SAM -Sympathetic Adrenal Medullary` (SAM) system, is the‘fast’ reaction to sudden stress. The hypothalamus activates thesympathetic branch of the autonomic nervous system (ANS), whichstimulates the adrenal medulla, which leads to the release of adrenalineand noradrenaline, which is called the ‘Fight or Flight’ syndrome. Thisleads to the physiological changes associated with stress, e.g. increasedheart rate, raised blood pressure, sweating and shaking ect.HPA- Hypothalamic Pituitary Adrenal (HPA) system, which is ‘slow’acting and is seen as the bodies stress system by controlling the levelsof cortisol and other hormones that are related to stress.What happens is the hypothalamus sends messages to the pituitarygland, which leads to the production of the hormone ACTH. Thisstimulates the adrenal cortex, which then produces the cortisol (a stresshormone). This provides the steady flow of ‘fuel’ necessary to deal withthe demands of stressful situations that may be ongoing.