Mood disorders are also known as affective disorders. As the name suggests these disorders primarily affect the person’s mood. These disorders re typically episodic. In between episodes the individual may have no remarkable symptoms or problems.
The most common mood disorder is depression. It comes in various forms including clinical, major, unipolar, and bipolar. These terms can be overlapping.
Clinical depression is any depression where symptoms are severe enough and last long enough to require treatment.
Major depression is a clinical depression that meets specific diagnostic criteria. These criteria involve the duriation, functional impairment, and a group of both psychological and physiological symptoms.
Unipolar disorder is when a person has recurring major depressive episodes without manic symptoms.
Bipolar disorder is when a person experiences recurring depression and mania.
Serotonin and norepinephrine are two amines that appear to be of particular importance. These neurotransmitters are related to the symptoms and episodes of mood disorders.