Double Delusion: From 1 Different Sources
the situation in which a patient (the inducer) presents with delusional symptoms that he or she believes to be shared by someone else who is incapable of expressing them (typically a child or a pet). This is different from a *delusion by proxy, in which the inducer does not claim to be experiencing the symptoms himself or herself. The term was introduced in 2015 by Peter Lepping, Mark Rishniw, and Roland Wolfgang Freudenmann. Compare folie à deux.
A scienti?c study in which di?erent patients receive a di?erent drug, the same drug at a different dose, or a placebo – with neither the investigators assessing the outcome nor the subjects being treated knowing which of these the latter are receiving. The aim is to remove any hint of bias due to the investigators’ or patients’ preferences or preconceptions. The results are analysed after all the data have been collected and the code has been broken. Trials should have a separate supervising committee, the members of which know the code but do not take part in the study. Their job is to check the results at intervals so they can stop the trial if one arm of treatment is clearly better than another. Otherwise, it would be unethical to continue. (See INTERVENTION STUDY.)... double blind trial
See SQUINT.... double vision
A fixed, irrational idea not shared by others and not responding to reasoned argument. The idea in a paranoid delusion involves persecution or jealousy. For instance, a person may falsely believe that he or she is being poisoned (see paranoia). Persistent delusions are a sign of serious mental illness, most notably schizophrenia and manic–depressive illness. (See also hallucination; illusion.)... delusion
An irrational and usually unshakeable belief (idée ?xe) peculiar to some individuals. They fail to respond to reasonable argument and the delusion is often paranoid in character with a belief that a person or persons is/are persecuting them. The existence of a delusion, of such a nature as to in?uence conduct seriously, is one of the most important signs in reaching a decision to arrange for the compulsory admission of the patient to hospital for observation. (See MENTAL ILLNESS.)... delusions
a *monodelusional disorder in which patients believe they or their environment are infested by living or non-living pathogens. These can range from rats in the patient’s house to microspores in the air. Most commonly, patients claim they are infested with insects, worms, parasites, mites, or inanimate threads or fibres, often underneath their skin. Many present the alleged parasite as a specimen for examination. If compliance can be established, most patients respond well to *antipsychotic medication. The term delusional infestation was first introduced by Roland W. Freudenmann and Peter Lepping in 2009, and has gradually superseded the terms delusional parasitosis and Ekbom’s syndrome.... delusional infestation
the intensity with which a delusional belief is held. This can vary over time and sometimes shifts quite rapidly. Some factors, such as treatment, may temporarily or permanently reduce the intensity of a delusion, while others may work to reinforce it.... delusional intensity
a *delusional belief that one’s partner is unfaithful when there is no reasonable evidence for this. It often occurs in the context of *alcoholism.... delusional jealousy
see delusional infestation.... delusional parasitosis
a *Schneiderian first-rank symptom in which a person believes that a normal percept (product of perception) has a special meaning for him or her. For example, a cloud in the sky may be misinterpreted as meaning that someone has sent that person a message to save the world. While the symptom is particularly indicative of *schizophrenia, it also occurs in other psychoses, including *mania (in which it often has grandiose undertones).... delusional perception
a *delusion in which the patient believes that unsuspicious occurrences refer to him or her in person. Patients may, for example, believe that certain news bulletins have a direct reference to them, that music played on the radio is played for them, or that car licence plates have a meaning relevant to them. Ideas of reference differ from delusions of reference in that insight is retained.... delusion of reference
a technique usually used in X-ray examinations of the bowel. Barium sulphate *contrast medium (first contrast) is used to coat the bowel wall. The bowel is then distended with gas (second contrast). The X-ray images obtained give exquisite detail of the lining of the gut. See also barium enema; barium swallow and meal.... double contrast
see stent.... double j stents
(DORV) a congenital defect of the heart in which both the aorta and the pulmonary artery arise predominantly from the right ventricle anterior to the ventricular septum with an associated *ventricular septal defect (VSD). The relationship between the site of the VSD and the great arteries must be taken into account for surgical repair. DORV can be associated with chromosomal defects.... double-outlet right ventricle
see uterus didelphys.... double uterus
see folie à deux.... shared delusion
a delusion in which the patient believes that another person or an animal (usually the patient’s pet) has certain physical symptoms, even though these cannot be objectively verified. The patient with the delusional belief is called the inducer; the person or pet that is allegedly affected is the proxy. Some *monodelusional disorders, such as *delusional infestation, have a prevalence of delusion by proxy of up to 5%. Treatment is usually with *antipsychotics. In some situations it may be necessary to remove the proxy to provide safety from the behaviour associated with the delusion. See also double delusion; folie à deux.... delusion by proxy
the principle that, where it is foreseen that a single action will have both a good and a bad outcome, a person may perform such an action provided that (a) he or she intends only the positive outcome, (b) the bad outcome is not disproportionate to the good, and (c) the good outcome is not a direct consequence of the bad. The classic example occurs where a terminally ill patient requires high doses of opiates for pain relief that may also depress respiratory function and hasten his or her death. In such a case the law holds that the doctor may supply the necessary dosage without this being considered tantamount to *euthanasia, even though the outcome will be the same, i.e. the morality of the action does not lie in its consequences (see consequentialism).... doctrine of double effect