Stress is a normal part of life. However, that doesn’t mean that it comes without its warnings. A significant number of studies have linked stressful life events to the development of depression. This may be due to multiple factors, like a lack of serotonin, excessive levels of cortisol, hyperactivity in the amygdala, and hypoactivity in the hippocampus. These stressful life events can include moments of overworking, huge life changes, and traumatic events. The more stress a person is exposed to, the more vulnerable they are to experiencing the negative impacts it can have, like depression.