Why is MAJOR depression caused???
There is no single cause of major depression. Psychological, biological, and environmental factors may all contribute to its development. Whatever the specific causes of depression, scientific research has firmly established that major depression is a biological, medical illness.
Norepinephrine, serotonin, and dopamine are three neurotransmitters (chemical messengers that transmit electrical signals between brain cells) thought to be involved with major depression. Scientists believe that if there is a chemical imbalance in these neurotransmitters, then clinical states of depression result. Antidepressant medications work by changing the sensitivity of the receptors for these chemical messengers or by increasing the availability of neurotransmitters
Evidence of a genetic predisposition to major depression Scientists are also found. When there is a family history of the illness there is an bigger risk for developing depression. Some people probably have a biological make-up that leaves them particularly vulnerable to developing depression with a genetic predisposition develops depression, but. Life events, such as the death of a loved one, a major loss or change, chronic stress, and alcohol and drug abuse, may trigger episodes of depression. Some illnesses such as heart disease and cancer and some medications may also trigger depressive episodes. It is also important to note that many depressive episodes occur spontaneously and are not triggered by a life crisis, physical illness, or other risks.
