Depression is a significant cause of disability and morbidity, resulting in tremendous suffering in the lives of many people. It can occur in isolation or in association with multiple medical, psychiatric, and neurological disorders, and can even mimic other diseases. In fact, depression can present with such debilitating impairments in memory, learning, perception, understanding, and the consolidation of information, that it’s symptoms can fool providers into thinking that their patients have dementia. The varied appearances of depression can make it difficult to recognize, difficult to diagnose, and therefore difficult to treat.
The diverse symptoms that depression can present with are not arbitrary manifestations of a sad state of mind. Instead they are a sign of the structural and microscopic changes that take place in the brains of depressed individuals. Neuroimaging studies show that major depressive disorder is associated with decreased volume in areas of the brain crucial to memory, emotional stability, the ability to learn new information, motivation, decision making capabilities, sleep, sex, eating, and the stress response.