What causes Depression?
It is difficult to give one cause for depression as it is often a combination of several factors, as outlined below:
Research has shown that depression is a disturbance in the balance of certain substances in the brain (such as serotonin, norepinephrine and growth factors such as BDNF). However, recent research also shows that this is more complex than just a reduced serotonin level. Also, recent research has shown that depression is associated with a specific pattern of disturbed brain activity as well as the extent to which certain areas of the brain communicate. Treatment with rTMS is specifically aimed at restoring communication between brain regions (e.g. dorsolateral prefrontal cortex, anterior cingulate).
A specific form of depression is associated with shortened daylight, called Seasonal Affective Disorder (or SAD) which is mainly caused by light deficiency. Light therapy can be used to prevent this kind of depression.
Genetic components also play a role in depression. Children of parents with depression are three times as likely to also experience depression as compared to children of parents who have not had depression.
Major life events such as divorce, death, resignation, promotion or the arrival of a child can play a significant role in the development of depression. These are events that can evoke a lot of tension and stress.
Often depressive episodes can be alleviated through a healthy and active social life. Stable employment, stable relationships and frequent contact with friends, particularly those who are supportive, often give a person a form of a social safety net for better stability and life-structure.
Blocking painful feelings and thoughts through unprocessed traumatic (childhood) experiences can increase the onset of depression.
Certain medications and different types of drugs (some high blood pressure medications, sedatives, alcohol, amphetamine, cocaine) are known to be a possible cause of depression. There are also a number of physical disorders which increase the risk of depression, such as stroke.