A psychosomatic illness is one in which a bodily ailment is, at least in part, attributable to emotional factors. The role of anxiety and its emotional derivatives is a key concept of psychosomatic medicine and clinical studies have shown the temporal relation between the course of a patient's disease and the emotional vicissitudes of his life. In psychosomatic illnesses, the anxiety associated with a stressful situation is generally unconscious, but the physical repercussions of the emotion occur just the same.
The bodily reactions that accompany emotion serve a useful purpose when the emotion is temporary and appropriate. Fear or anger, for example, in the face of external danger or threat arouses a defensive response. Once appropriate action has been taken, the physiological emotional changes that have enabled the individual to reach into his reserves of strength usually subside. However, when the emotions are not discharged, due to being unconscious and part of a basic personality conflict, or because the person is involved in a repetitive and inescapable situation, the physical effects persist. Tissue change in an organ may be the end result. Thus, psychosomatic symptoms are the instruments that a patient has unconsciously adopted to handle some difficult situation. Although he consciously desires relief from his physical suffering, he will unconsciously resist relinquishing these safety mechanisms until some solution for the underlying problem seems imminent.