Psychology 101 and the Brain: Stress – Definition, Symptoms, and Health Effects of the Fight-or-Flight Response

The “fight or flight” response is in response to impending danger. For example, the stress responses kicks in when seeing a snake slithering towards you or running away from a bear in the woods. Homeostasis is the normal equilibrium of body function, so stress can be induced by belief that homeostasis might be interrupted. In this guide, we share the effects of stress on the human body system, psychology, immune system, and long-term health effects of chronic stress.