According to the current literature a combination of personal factors contributes to the cause of depression:
Environment: An environmental factor can be anything that is affecting us in our immediate surroundings. Examples may be unemployment, violence in the home, prolonged stress at work or financial hardship.
Biology: Factors affecting each of us as living organisms; including genetic disposition, behaviour and origin. Biological factors that may contribute to depression are: family history of depression, battling another medical condition or drug & alcohol problems.
Psychology: Factors that relate to the mental and emotional state of a person. Examples may be early childhood experiences, personality traits such as perfectionism or low self-esteem, anxiety or other mental health diagnosis.
Social structure: Our social structure focuses on our relationships and interaction with those around us: caring for a sick family member, prolonged loneliness or isolation, bullying or divorce.
Alongside the study of the personal factors causing depression there is a growing body of research on the topic of physiology. Physiology, in relation to depression, looks at stress hormones, brain chemicals and brain configuration. The part of the brain, which centers around communication, is made up of chemicals and nerve cells called neurotransmitters. When neurotransmitters are altered or reduced the body’s functioning is affected. The three neurotransmitters that are believed to be associated with depression are serotonin, dopamine and norepinephrine, because they are involved in regulating mood, behaviour and emotions.
Depression is not simply the result of a chemical imbalance. Depression is caused by a combination of physiology and personal factors, it is important to understand depression in terms of the interactions between biological, social and psychological processes.