There are diseases that affect any and all organs in the human body. Yet we tend to really know only a few major ones, such as heart disease, bowel or stomach diseases, respiratory and ear, nose and throat diseases . . . things we can see, touch and feel. But do we stop and think about the organ that does the recognizing, interpreting, feeling and knowing? The brain? The organ that accounts for nearly half the oxygen and nutrients we expend? Yes. The brain. And in the brain, there are pathways, circuits and physical areas through which and in which various operations occur. Everything we do, perceive or think has a physical place in the brain with neuron circuits to do the particular task. So there are areas that process and/or generate emotions, and these areas have connections to the rest of the brain.

Depression is a brain illness, and really is no different than having a heart illness, hypertension or diabetes. And we don't have any more control over getting depression than we do over having diabetes or hypertension! Many people, as many as fifteen percent, have a period of serious depressive illness during their lives, if not recurring episodes, and some have essentially continuous depression.

Depression is a serious medical condition. In contrast to the normal emotional experiences of sadness, loss, or passing mood states, clinical depression is persistent and can interfere significantly with an individual's ability to function.