Intermetamorphosis is a

delusional misidentification syndrome Delusional misidentification syndrome is an umbrella term, introduced by Christodoulou (in his book ''The Delusional Misidentification Syndromes'', Karger, Basel, 1986) for a group of delusional disorders that occur in the context of mental and n ...

, related to

agnosia Agnosia is the inability to process sensory information. Often there is a loss of ability to recognize objects, persons, sounds, shapes, or smells while the specific sense is not defective nor is there any significant memory loss. It is usually ...

. The main symptoms consist of patients believing that they can see others change into someone else in both external appearance and internal personality. The disorder is usually

comorbid In medicine, comorbidity - from Latin morbus ("sickness"), co ("together"), -ity (as if - several sicknesses together) - is the presence of one or more additional conditions often co-occurring (that is, concomitant or concurrent) with a primary ...

with

neurological disorder A neurological disorder is any disorder of the nervous system. Structural, biochemical or electrical abnormalities in the brain, spinal cord or other nerves can result in a range of symptoms. Examples of symptoms include paralysis, muscle weakn ...

s or

mental disorder A mental disorder, also referred to as a mental illness or psychiatric disorder, is a behavioral or mental pattern that causes significant distress or impairment of personal functioning. Such features may be persistent, relapsing and remitti ...

s. The disorder was first described in 1932 by Paul Courbon (1879–1958), a French psychiatrist.''Illusions d'intermétamorphose et de la charme'', Annales Medico-Psychologiques, issue 14, page 401-406. Intermetamorphosis is rare, although issues with diagnostics and comorbidity may lead to under-reporting.Cipriani, G., Vedovello, M., Ulivi, M., Lucetti, C., Fiorino, A. D., & Nuti, A. (2013). Delusional Misidentification Syndromes and Dementia: A Border Zone Between Neurology and Psychiatry. American Journal of Alzheimer’s Disease & Other Dementias, 28(7), 671–678.

Signs and symptoms

Individuals experiencing intermetamorphosis, as well as the other

s (DMS), tend to misidentify those people that are both physically and emotionally close to them; the most commonly misidentified people are parents, siblings and spouses.Silva, J. A., Leong, G. B., & Weinstock, R. (1992). The dangerousness of persons with misidentification syndromes. Bulletin of the American Academy of Psychiatry & the Law, 20(1), 77–86. There are instances of individuals misidentifying people not known to them, however, they still held an affective importance, such as celebrities or politicians. The explanations for the inauthenticity of the misidentified people are associated with the individual experiencing the delusions’ cultural background.

Example

An example from medical literature is a man who was diagnosed with Alzheimer's disease. He mistook his wife for his deceased mother and later for his sister. He explained that he had never been married or that his wife had left him. Later he mistook his son for his brother and his daughter for another sister. Visual agnosia or

prosopagnosia Prosopagnosia (from Greek ''prósōpon'', meaning "face", and ''agnōsía'', meaning "non-knowledge"), also called face blindness, (" illChoisser had even begun tpopularizea name for the condition: face blindness.") is a cognitive disorder of fa ...

were not diagnosed, as the misidentification also took place during phone calls. On several occasions he mistook the hospital for the church he used to go to.

Violence

There is an association in the literature between misidentification syndromes and violent or aggressive behavior. De Pauw, K. W., & Szulecka, T. K. (1988). Dangerous delusions: Violence and the misidentification syndromes. The British Journal of Psychiatry, 152, 91–96.Förstl, H., Almeida, O., Owen, A., Burns, A., & Howard, R. (1991). Psychiatric, neurological and medical aspects of misidentification syndromes: A review of 260 cases. Psychological Medicine, 21(4), 905–910.Klein, C. A., & Hirachan, S. (2014). The masks of identities: Who's who? delusional misidentification syndromes. Journal of the American Academy of Psychiatry and the Law, 42(3), 369–378. In several case studies, individuals with misidentification syndromes acted aggressively towards the object of misidentification, which has the potential for criminal behavior. This may be because the delusions cause individuals to view the misidentified object with suspicion, and they become paranoid about the inauthenticity of the object, leading to an act of presumed preemptive self-defense. Although gender differences in the occurrence of intermetamorphosis are not pronounced, the research demonstrates that a majority (70%) of occurrences with violent behavior involves males. The issue of violent and aggressive behavior within this set of syndromes continues to play an important role in the discussion of criminal responsibility and risk assessment.

Comorbidity

Intermetamorphosis and other DMSs often occur together or interchange. DMSs are also often comorbid with psychiatric disorders, such as

schizophrenia Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social wi ...

schizoaffective disorder Schizoaffective disorder (SZA, SZD or SAD) is a mental disorder characterized by abnormal thought processes and an unstable mood. This diagnosis is made when the person has symptoms of both schizophrenia (usually psychosis) and a mood disorder: ...

, bipolar disorder, and

PTSD Post-traumatic stress disorder (PTSD) is a mental and behavioral disorder that can develop because of exposure to a traumatic event, such as sexual assault, warfare, traffic collisions, child abuse, domestic violence, or other threats on a ...

Paranoid schizophrenia Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social withd ...

is most commonly associated with DMSs. They are also associated with neurological conditions or diseases, including

dementia Dementia is a disorder which manifests as a set of related symptoms, which usually surfaces when the brain is damaged by injury or disease. The symptoms involve progressive impairments in memory, thinking, and behavior, which negatively affe ...

Alzheimer’s disease Alzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As ...

and alcohol- or drug-induced cognitive impairment. Among comorbid symptoms, paranoid psychotic symptoms, depressive psychotic symptoms and

auditory hallucinations An auditory hallucination, or paracusia, is a form of hallucination that involves perceiving sounds without auditory stimulus. While experiencing an auditory hallucination, the affected person would hear a sound or sounds which did not come from ...

are the most often present.

Cause

Explanations for the occurrence of intermetamorphosis were first given by

psychodynamic Psychodynamics, also known as psychodynamic psychology, in its broadest sense, is an approach to psychology that emphasizes systematic study of the psychological forces underlying human behavior, feelings, and emotions and how they might relate t ...

theorists. Young, A. H., Ellis, H. D., Szulecka, T. K., & de Pauw, K. W. (1990). Face processing impairments and delusional misidentification. Behavioural Neurology, 3(3), 153–168. These theories typically involve a psychotic resolution towards an individual’s feelings of intense ambivalence about the misidentified object. These theories may also involve the egos and identity-forming, as well as defense mechanisms involving splitting the negative and positive aspects of the self. Despite their initial popularity, there is not much empirical support for these psychodynamic explanations. Recent advancements in neuroimaging and structural studies have provided evidence of an organic etiology. Neurological dysfunction and neuropsychiatric abnormalities, in various forms, are now believed to be a central feature in DMSs. Neuropsychological findings suggest that symptoms are produced in some aspect by brain dysfunction or damage, specifically in the right hemisphere. Christodoulou, G.N., Margariti, M., Kontaxakis, V.P. (2009). The delusional misidentification syndromes: Strange, fascinating, and instructive. Current Psychiatry Reports, 11, 185–189. Lesions in the right frontal lobe and adjacent areas have been found through neuroimaging in case reports of intermetamorphosis. In studying over 20 patients with misidentification syndromes, Christodoulou found

electroencephalograph Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The biosignals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocorte ...

ic abnormalities in over 90%. In one case of intermetamorphosis, Joseph reported electroencephalographic abnormalities with right temporo-parietal predominance. Impaired connectivity or dysconnectivity between the right fusiform and right parahippocampal areas and the

frontal lobe The frontal lobe is the largest of the four major lobes of the brain in mammals, and is located at the front of each cerebral hemisphere (in front of the parietal lobe and the temporal lobe). It is parted from the parietal lobe by a groove b ...

s and the right temporolimbic regions have also been seen in case reports of this syndrome, which are thought to be implicated in deficits in face recognition, visual memory recall, and identification processes. While impairments in facial processing are experienced by most DMSs, it appears to be experienced more consciously in intermetamorphosis than in other DMSs. Cortical atrophy is also sometimes present, although this may be due to co-occurring

and other organic mental syndromes. Overactivity in the

perirhinal cortex The perirhinal cortex is a cortical region in the medial temporal lobe that is made up of Brodmann areas 35 and 36. It receives highly processed sensory information from all sensory regions, and is generally accepted to be an important region ...

appears to be associated with the loss of familiarity in intermetamorphosis. Depersonalization has also been postulated as a contributing factor to the development of intermetamorphosis; under conditions like the presence of a paranoid element, a charged emotional relationship to the principal misidentified person, and cerebral dysfunction,

depersonalization Depersonalization can consist of a detachment within the self, regarding one's mind or body, or being a detached observer of oneself. Subjects feel they have changed and that the world has become vague, dreamlike, less real, lacking in significa ...

and

derealization Derealization is an alteration in the perception of the external world, causing those with the condition to perceive it as unreal, distant, distorted or falsified. Other symptoms include feeling as if one's environment is lacking in spontaneity, ...

symptoms may develop into a full delusional misidentification syndrome.

Diagnosis

How to define intermetamorphosis and other delusional misidentification syndromes is frequently debated in the literature. Some believe that misidentification is a symptom, and that the overlapping nature of these syndromes suggests that they are “states” associated with other psychiatric or neurological disorders, but that they're not diagnostic in themselves. As their name suggests, many professionals consider them syndromes, because misidentification appears to occur more often in association with certain symptoms, like depersonalization, derealization, and paranoia. Lastly, some believe that they should be discrete diagnoses in the Diagnostic and Statistical Manual of Mental Disorders.

Treatment

Results regarding the efficacy of treatments for intermetamorphosis are mixed. Treatment of any co-occurring mental disorder or substance abuse is necessary. There have been no controlled studies about pharmacological treatments of intermetamorphosis. However, both atypical and typical

antipsychotics Antipsychotics, also known as neuroleptics, are a class of psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but also in a range of oth ...

are often used, and have been found to be effective in patients with both organic and functional disorders. Some that have been effective in case studies are

clozapine Clozapine is a psychiatric medication and is the first atypical antipsychotic (also called second-generation antipsychotic). It is primarily used to treat people with schizophrenia and schizoaffective disorders who have had an inadequate resp ...

olanzapine Olanzapine (sold under the trade name Zyprexa among others) is an atypical antipsychotic primarily used to treat schizophrenia and bipolar disorder. For schizophrenia, it can be used for both new-onset disease and long-term maintenance. It is ta ...

risperidone Risperidone, sold under the brand name Risperdal among others, is an atypical antipsychotic used to treat schizophrenia and bipolar disorder. It is taken either by mouth or by injection (subcutaneous or intramuscular). The injectable versions ...

quetiapine Quetiapine, sold under the brand name Seroquel among others, is an atypical antipsychotic medication used for the treatment of schizophrenia, bipolar disorder, and major depressive disorder. Despite being widely used as a sleep aid due to its ...

sulpiride Sulpiride, sold under the brand name Dogmatil among others, is an atypical antipsychotic (although some texts have referred to it as a typical antipsychotic) medication of the benzamide class which is used mainly in the treatment of psychosis a ...

trifluoperazine Trifluoperazine, marketed under the brand name Stelazine among others, is a typical antipsychotic primarily used to treat schizophrenia. It may also be used short term in those with generalized anxiety disorder but is less preferred to benzodiaze ...

pimozide Pimozide (sold under the brand name Orap) is an antipsychotic drug of the diphenylbutylpiperidine class. It was discovered at Janssen Pharmaceutica in 1963. It has a high potency compared to chlorpromazine (ratio 50-70:1). On a weight basis ...

haloperidol Haloperidol, sold under the brand name Haldol among others, is a typical antipsychotic medication. Haloperidol is used in the treatment of schizophrenia, tics in Tourette syndrome, mania in bipolar disorder, delirium, agitation, acute psychos ...

and

carbamazepine Carbamazepine (CBZ), sold under the trade name Tegretol among others, is an anticonvulsant medication used primarily in the treatment of epilepsy and neuropathic pain. It is used as an adjunctive treatment in schizophrenia along with other medi ...

Clorazepate Clorazepate, sold under the brand name Tranxene among others, is a benzodiazepine medication. It possesses anxiolytic, anticonvulsant, sedative, hypnotic, and skeletal muscle relaxant properties. Clorazepate is an unusually long-lasting benzodiaz ...

, a

benzodiazepine Benzodiazepines (BZD, BDZ, BZs), sometimes called "benzos", are a class of depressant drugs whose core chemical structure is the fusion of a benzene ring and a diazepine ring. They are prescribed to treat conditions such as anxiety disorders, ...

used in the treatment of

anxiety Anxiety is an emotion which is characterized by an unpleasant state of inner turmoil Turmoil may refer to: * ''Turmoil'' (1984 video game), a 1984 video game released by Bug-Byte * ''Turmoil'' (2016 video game), a 2016 indie oil tycoon video ...

and

seizure An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with l ...

disorders, has also been used effectively. Joseph, A. B. (1987). Delusional misidentification of the Capgras and intermetamorphosis types responding to clorazepate. Acta Psychiatrica Scandinavica, 75, 330–332. Occasionally,

antidepressants Antidepressants are a class of medication used to treat major depressive disorder, anxiety disorders, chronic pain conditions, and to help manage addictions. Common side-effects of antidepressants include dry mouth, weight gain, dizziness, heada ...

and

lithium Lithium (from el, λίθος, lithos, lit=stone) is a chemical element with the symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the least dense metal and the least dense solid ...

have been used, especially in the instance of a co-occurring mood or bipolar disorder.

Reverse Intermetamorphosis

A proposed variant of intermetamorphosis is the syndrome of “reverse” intermetamorphosis, in which there is the delusional belief that an individual is undergoing radical changes in both physical and psychological identities.

References

{{Delusion Psychosis Delusional disorders Delusions