Clinical Depression is often caused by a chemical imbalance, usually serotonin. It isn't being "sad" and doesn't usually have root cause in a certain event or d

Clinical Depression is often caused by a chemical imbalance, usually serotonin. It isn't being "sad" and doesn't usually have root cause in a certain event or direct emotion - though those things can trigger the already existing issue. We have to remember that the term Depression in this sense doesn't mean what it means in the common sense. Just like words like "Theory" have different meanings in the common vernacular. It's closer to Anxiety than it is to Sadness.