There are many different types of depression, and the causes for depression are varied and extensive. Depression could be the result of chemical imbalances in a person’s brain. Medication can help with these imbalances to reduce the symptoms, or sometimes, to relieve them completely.  Even when the depression is situational, the depression does not always show up at the time the causative event occurs. This makes determining the reason for depression difficult. 

For example, a five-year-old child loses her mother. We know such a loss can have a profound effect on a child’s psychological development, but the effect on the child, and the potential resultant depression, might not show up for many years. In this situation, it might be difficult to determine the cause of the depression when it appears, but once the history is known, the cause is fairly straightforward.