Power of suggestion

Psychosomatic medicine is an interdisciplinary medical field exploring the relationships among social, psychological, and behavioral factors on bodily processes and quality of life in humans and animals.

The academic forebear of the modern field of behavioral medicine and a part of the practice of consultation-liaison psychiatry, psychosomatic medicine integrates interdisciplinary evaluation and management involving diverse specialties including psychiatry, psychology, neurology, internal medicine, surgery, allergy, dermatology and psychoneuroimmunology. Clinical situations where mental processes act as a major factor affecting medical outcomes are areas where psychosomatic medicine has competence.

Some physical diseases are believed to have a mental component derived from the stresses and strains of everyday living. This has been suggested, for example, of lower back pain and high blood pressure, which some researchers have suggested may be related to stresses in everyday life. However, within a psychosomatic framework, mental and emotional states are seen as capable of significantly influencing the course of any physical illness. Psychiatry traditionally distinguishes between psychosomatic disorders, disorders in which mental factors play a significant role in the development, expression, or resolution of a physical illness, and somatoform disorders, disorders in which mental factors are the sole cause of a physical illness.

It is difficult to establish for certain whether an illness has a psychosomatic component. A psychosomatic component is often inferred when there are some aspects of the patient's presentation that are unaccounted for by biological factors, or some cases where there is no biological explanation at all. For instance, Helicobacter pylori causes 80% of peptic ulcers. However, most people living with Helicobacter pylori do not develop ulcers, and 20% of patients with ulcers have no H. pylori infection. Therefore, in these cases, psychological factors could still play some role. Similarly, in irritable bowel syndrome (IBS), there are abnormalities in the behavior of the gut. However, there are no actual structural changes in the gut, so stress and emotions might still play a role.

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