Explain the fight or flight response (to acute stressors)

An acute stressor can trigger the fight or flight response in animals. The amygdala is activated which sends a stress response to the hypothalamus, this activates the sympathetic nervous system (SNS). The SNS tiggers the adrenal medulla to release adrenaline. The release of adrenaline into the bloodstream causes a number of physiological changes in the body which prepares the body for action. After the threat has passed the parasympathetic nervous system (also known as the rest and digest system), is activated and it allows the body to go back to its normal resting state.