Depression is a depressive disorder that negatively affects the way you think and act. Depression can cause feelings such as sadness, It can also lead to a loss of interest in activities. Unlike sadness depression is a medical condition affecting the way mood is controlled in the brain. Changes in brain chemistry can lead to depression.. Many factors can contribute to this such as genetics, changes in hormone levels, stress and certain life circumstances. These factors can lead to changes in brain chemistry which in turn can cause depressive symptoms. Teen depression and suicidal actions have dramatically increased by nearly doubling in the past decade in the U.S. According to Approximately 20% of teens will experience depression before they reach adulthood. Drugs and alcohol may also be used by teens with depression as a way to cope. Depression in teens can also lead to many eating disorders such as bulimia, anorexia l, as well as binge eating. Teens with depression cannot control how they feel but they can choose their food intake. Depression may also cause a teen to eat more in which they may gain weight which can have negative consequences on their self esteem. Depression in teens can lead to violence. Suicidal thoughts such as self hatred and a wish to die can cause violent and homicidal rage. Teens with depression may engage in activities such as self harm which include cutting, burning and others types of self mutilation. Self harm is a sign that teens really don’t care about their bodies, themselves, or their futures. This is a sign of severe depression in teens that may even lead to committing suicide. The the hippocampus, amygdala, and prefrontal cortex are the three main parts of the brain that play a role in clinical depression. The body releases cortisol when it has feelings of stress, anxiety, or depression. When too much cortisol is sent to the brain due to chemical imbalance in the body and emotional imbalance in the mind that cause this, problems can occur. People with clinical depression can not be exposed to too much increased cortisol levels in the brain because it slows down the production of brain cells. The brain’s emotional response is affected by the amygdala. In people with clinical depression, the amygdala becomes enlarged and more active due to the constant flow of cortisol in the brain. An enlarged and more activated amygdala, with added abnormalities in the brain, can result in disturbances in sleep and activity patterns in people’s everyday lives. Leading to even further complications, an enlarged amygdala can also cause the body to release irregular amounts of hormones.High cortisol levels affect many parts of the brain triggering clinical depression. Normally cortisol levels are highest in the morning and the lowest at night. However in people with depression it is totally different. People with depression have high cortisol levels all the time, even at night.