But for people who suffer with depression, those days seem to never end. Thoughts and feelings of uselessness, worthlessness and hopelessness crowd out all others. Clinically, depression is the lack of neurotransmitters that send signals from one nerve to another in the brain, causing a chemical imbalance. There is no single factor that can be blamed for this disorder.
Depression can be the result of various factors ranging from hormones to hard times.
The biochemical effect that occurs in the brain can be triggered by major events in a person's life such as death, divorce, a traumatic experience or job. Heredity may also play a role. Studies have shown vulnerability from generation to generation among families with a history of depression. However, not everyone with the genetic make up will develop a depressive disorder. Temperament may also contribute to a person's susceptibility to depression.