psychogenic adj : mental or emotional rather than physiological in origin; "a psychogenic disorder"
A psychogenic disease is a set of symptoms or complaints whose origin likely lies within the complex interactions of the frontal lobes of the brain and the system in which the complaint manifests. These disorders can often result from mental or emotional conflict. In most cases, a structural or anatomical abnormality has not been identified, as seen in an organic disease, however this does not account for possible genetic, biochemical, electrophysiological or other abnormalities that may be present but for which we do not have the technology or background to identify them. The traditional duality that divided mind from body is no longer accepted by the mainstream of science. There is a multitude of evidence to implicate the frontal lobes of the brain, where the most complex aspects of cognition, personality, mood, and memory are processed, as the mediators if not the source of psychogenic complaints.
Psychogenic is a broader category than psychosomatic, in that it can include the hysterical form, where there is no physiologic change in peripheral tissues, as well as the psychosomatic form, where there is some physiologic alteration.
Psychogenic Amnesia is a debated form of amnesia related to trauma or general psychological disorientation.
Psychogenic pain is pain that cannot be linked to physical symptoms - instead, it is psychological in origin. Psychogenic pain is thought to be a physical manifestation of (often unexpressed) emotional pain, or stress, which themselves are mediated by biochemical and electrophysiological activity within the brain. It is as real and painful as non-psychogenic pain.