The hypothalamus (control center) recognizes a threat (stimulus) or type of danger by receiving a message visually or audibly (receptors) from the amygdala and notifies two systems, the sympathetic nervous system and the adrenal-cortical system (effectors) to kick into gear and go into protection mode. The sympathetic nervous system speeds up the body by tensing up and becoming very alert along with sending impulses to glands and smooth muscles. It will also inform the adrenal medulla to release epinephrine, which is adrenaline into the bloodstream. At the same time, the hypothalamus also releases corticotrophins into the pituitary gland, which then activates the adrenal-cortical system. From there, the hormone moves through the bloodstream
