Affective Disorders as Diseases

Efforts to link affective disorders to external circumstances have yielded distinctions between mourning and melancholia (Freud), and reactive versus endogenous depression. But if it is unclear whether stress causes depression or vice versa, then a simpler, assumption-free explanatory model is required if we are to understand the normal dejection that results from, say, a romantic setback, versus the prolonged sadness that accompanies the grieving process, versus a pathological affective disorder.

Unlike emotional reactions, affective disorders are clinical syndromes with stereotypical patterns of sign, symptoms, course, and treatment response. Unlike grieving, affective disorders are associated in some cases with known brain disease. Affective disorders are best understood as medical diseases, i.e., as syndromal entities emerging from biological dysfunction in the brain and body.

Like other medical diseases, affective disorders are not limited by culture, intelligence, education, socioeconomic status, or experience. Nor do the symptoms of affective disorder vary much across cultures, although one might expect to see culturally and individually specific manifestations of these symptoms.

The typical symptoms of affective disorder cluster over a similar course and respond to the same biological treatments anywhere in the world. Affective disorders, moreover, may arise from known medical causes. Huntington’s disease, a genetic disorder of progressive dementia and abnormal movement, carries a high risk for manic-depressive disorder. Some patients develop their first depression after a stroke (particularly a stroke in the left frontal part of the brain).

Certain medications can cause a clear depressive syndrome; knowledge of the pharmacology of such drugs spawned research into medications to reverse the depressive syndrome. Cortisol-like drugs (e.g., prednisone) frequently induce manic symptoms in people with no history of affective disorder. If such known changes to the anatomy and biochemistry of the brain can trigger the characteristic signs and symptoms of affective disorder, then it seems reasonable to conclude that the commonly observed affective disorders arise from biological mechanisms as yet unknown, but knowable.

In contrast, clinical problems related to mood alone are strongly culture bound and uniquely expressed, generally have few if any symptoms other than a bad mood, and cannot be mimicked by drugs or other medical diseases. Unpleasant or unmanageably intense mood reactions of this sort are best viewed primarily as discouragement, demoralization, the blues, or in the official nomenclature, adjustment disorders.

Grief, on the other hand, has a syndromal quality to it, with characteristic sensations: the welling-up feeling, the false recognition of the departed in a crowd. Uncomplicated grief is not a disease, of course, but a normal part of human experience: painful, but rich with personal meaning. In real clinical situations, it is not always simple to distinguish grieving from moping from depression, but it is essential to try.