A psychological disorder, also called hysterical conversion, in which the affected individual presents with striking neurological symptoms – such as weakness, paralysis, sensory disturbances or memory loss – for which no evidence can be found for an organic cause. Up to 4 per cent of patients attending neurological outpatient clinics have been estimated as having conversion disorders. The disorder remains controversial, with theories about its cause unsupported by controlled research results. In clinical practice the physician's experience and intuition are major factors in diagnosis. It has been suggested that the physical symptoms represent guilt about a physical or emotional assault on someone else. Treatment using a COGNITIVE BEHAVIOUR approach may help those with conversion disorders.