Conversion reaction. Differential diagnoses in the light of biofeedback research.

The criteria for differentiating between psychophysiological disorder and hysterical neurosis, conversion type, have been reviewed in the light of recent biofeedback research. The data strongly support the view that a single process, instrumental learning, can explain functional disorders mediated by either the voluntary or autonomic nervous systems, so that a differential diagnosis should probably not be based on the autonomic/voluntary dichotomy. On the contrary, both biofeedback findings and a case history support the definition of conversion reaction broadened to include fantasied bodily sensations that develop into either behavioral or physiological dysfunctions. It is a central consideration that instrumental learning depends on a system of rewards, and that, in clinical observations of conversion reactions, it also is apparent that the conversion sympton is rewarding: the sympton provides the patient with a relatively gratifying adaptation to a frustrating stressful life experience. Classification of many, if not most, functional disorders mediated by the autonomic nervous system as conversion reactions has the advantage of emphasizing the primary and secondary gain characteristics of these symptoms. Thus, the use that the patient makes of his illness becomes salient in the therapeutic process at the same time that the diagnosis is established.