Capgras Syndrome Research Articles

Against a second factor

In his recent book Delusions and Beliefs, Kengo Miyazono offers a thoroughgoing defence of delusions as biologically malfunctioning beliefs, greatly elaborating on his earlier (2015) defence of this view. Miyazono has it that delusions have biological doxastic functions (i.e. functions specific to belief), and that delusions involve direct or indirect malfunctions of this kind. In this short piece, I focus on Miyazono’s defence of a two-factor approach to delusion formation as it appears in Chapter Four (Etiology). Miyazono approaches his discussion of the debate between one- and two-factor theories having already defended the key thesis of the book: that delusions are malfunctioning beliefs. Of course, that thesis might be thought to mesh nicely with the two-factor theorist’s claim that there is a cognitive abnormality present in delusion formation or maintenance. However, I will discuss Miyazono’s defence of the two-factor position in isolation from its role in his overall account of delusion. Miyazono abstracts away from the particulars of Max Coltheart’s two-factor view, and takes himself to be investigating the plausibility of two-factor theories without the specific commitments of Coltheart’s view (i.e. that the first factor of the Capgras delusion is not consciously accessible, and that the second factor is related to right hemisphere abnormalities). Miyazono also captures under the two-factor heading theories which locate the second factor in belief maintenance rather than just in belief formation. He puts forward a new argument for a two-factor approach which goes via inference to the best explanation. I begin by arguing that Miyazono’s starting motivation for a two-factor approach rests on a misrepresentation of the one-factor approach. Then, I turn to the four components of Miyazono’s inference to the best explanation argument, and argue that in each case, we do not have grounds for positing a second factor.

Young-Onset Dementia With Lewy Bodies With Capgras Syndrome

Young-Onset Dementia With Lewy Bodies With Capgras Syndrome

Capgras syndrome and poor facial emotion recognition

IntroductionCapgras syndrome is a disorder of personal identification characterized by the delusional belief that one or more persons close to the subject have been replaced by physically identical doubles.ObjectivesTo deepen our knowledge of the Capgras syndromeMethodsA case report about a Capgras syndrome.ResultsWe report the case of a 46-year-old female patient who was admitted in February 2021 for incoherent speech and behavior disorder against her family members. Three years ago, she started to have hypochondriacal concerns. A week before her admission, she threatened her husband with a knife and she was convinced that her daughters were dead and that they had been replaced by clowns. She had a Capgras delusion with a hallucinatory and interpretative mechanism against her daughters, she reported olfactory and cenesthetic hallucinations. Biological explorations and brain CT were normal. The PANNS scale showed a positive scale of 36, a negative scale of 39, the general psychopathology scale of 53. She had a total score of 30/40 on The Penn emotion recognition test. The patient had difficulty in recognizing low intensity emotions (0 or 1) and 50% of the false responses were for the neutral emotion with responses tending towards anger first and then sadness.Conclusions Capgras syndrome remains poorly described in the literature and the hypotheses concerning its origin often oscillate between neuropsychological and psychodynamic. With the recent advances in neuroscience, it would be interesting to deepen its physiopathology in order to place it in a more modern nosological framework.DisclosureNo significant relationships.

WHO IS THAT MAN I SEE STARING STRAIGHT BACK AT ME? - Mirror Delusional Misidentification: A Case Report And Literature Review

IntroductionThe delusional misidentification syndromes (DMS) are uncommon but fascinating neuropsychiatric disorders. One particularly intriguing form of DMS is called the mirror sign or mirror delusional misidentification (MDM).ObjectivesWe aim to present a case on MDM and a review on MDM and its correlation with neurological lesions.MethodsNon-systematic review of the literature and case report.ResultsA 72 years old patient was admitted to the emergency department with disorientation, behavioral changes and persecutory delusional ideation. The patient was also unable to recognize his face in the mirror, claiming to be his son. On neuroimaging tests, the patient presented with moderate diffuse cortical-subcortical cerebral atrophy associated with mild diffuse cortical cerebellar atrophy, as well as atheromatous calcifications in carotid siphons. In the MDM, the patient treats the mirror image as separate from the self. It is commonly seen in patients with dementia. Unlike Capgras syndrome, MDM is typically associated with neurological illness, particularly with neurodegenerative conditions. Findings on neuroimaging have shown a pattern of right hemisphere cortical and subcortical lesions. the most common findings included the following: generalized or localized atrophy on Magnetic Resonance Imaging, ventricular dilatation on Computed Tomography scan, and slowing on Electroencephalography.ConclusionsMirror delusional misidentification differs from other forms of DMS as it is seen exclusively in patients with neurological disease. While right hemisphere dysfunction appears to be a requirement for MDM, patients with this condition do not show consistent enough neuroimaging findings to allow for a localization within the right hemisphere.DisclosureNo significant relationships.

Fregoli syndrome in schizophrenia: about a case report

A Fregoli syndrome, just like Capgras Syndrome, Double Subjective Syndrome, and Inter metamorphosis Syndrome, belongs to the group of delusion misidentification syndromes. It is a rare neuropsychiatric pathology that could affect the brain with repercussions on behavior. It is the belief that a familiar person is disguised as a strange person by taking a different physical appearance but remains the same person psychologically. This entity has heterogonous etiologies, occurring mainly in the setting of organic diseases, affective disorders, or schizophrenia. In this article, we proposed to expose a case of a schizophrenic patient who developed Fregoli syndrome.

Treatment and Care for Elderly Patients with Dementia with Lewy Bodies Presenting with Delusional Misidentification Syndrome Including Capgras Syndrome: Severe Psychiatric Symptoms Associated with Dementia with Lewy Bodies

The treatment and care for severe psychiatric symptoms associated with dementia with Lewy bodies is challenging. This is especially true for elderly patients because the use of antipsychotics is associated with an attendant mortality risk. In this article, dementia patients with Lewy bodies who presented with severe psychiatric symptoms such as Capgras syndrome (delusional misidentification syndrome), are described, and pharmacological and non-pharmacological strategies to address these symptoms are discussed. Measures to be avoided include antipsychotic administration and physical restraint, both of which often lead to medical conditions and a bedridden status. Conversely, changing antiparkinsonian drugs (levodopa rather than dopamine agonists), cholinesterase inhibitor administration, physical rehabilitation, and providing a supportive, patient-friendly environment may help improve psychiatric symptoms or maintain functionality. In some cases, electroconvulsive therapy may be effective for severe psychiatric symptoms.

Treatment and Care for Elderly Patients with Dementia with Lewy Bodies Presenting with Delusional Misidentification Syndrome Including Capgras Syndrome: How to Respond and Intervene from a Neurologist's Perspective

Aged patients with dementia with Lewy body (DLB) present with delusional misidentification syndrome and occasionally Capgras' syndrome. It is difficult to treat the DLB patients presenting with these psychiatric symptoms, as well as dementia, parkinsonism, sleep disorders, and autonomic dysfunction. In advanced stage of DLB, it is necessary to pay careful attentions to the appropriate choice of drugs as well as to improve the environment surrounding the DLB patients. At an earlier stage of DLB, before the exacerbation of illness, it is important to explain the clinical features and treatments of various symptoms for the patient, their family members, and caregivers.

P496. Alice in Wonderland Syndrome as an Exordium to Capgras Syndrome in Schizoaffective Disorder

P496. Alice in Wonderland Syndrome as an Exordium to Capgras Syndrome in Schizoaffective Disorder

"ZOOM effect". The TV sign in patients with dementia: Is there an increased incidence during pandemia due to a rise in isolation and virtuality?

Delusional misidentification syndromes are misperceptions of external stimuli with an associated belief or elaboration that is held with delusional intensity. In the TV sign patient believes that the observed television events are occurring in a real three-dimensional space. It is one of the very rare forms of delusional misidentification syndrome in patients withdementia.Wereport7patientswithcognitiveimpairmentcaseswhohavepresentedTVsignduringtheCOVID-19 pandemic. Two patients had Alzheimer's dementia type diagnosis, 1 atypical Alzheimer dementia, 1 vascular dementia and 3 of them had mixed etiology (2 Alzheimer dementia + vascular and 1 dementia with Lewy bodies + vascular). Three presented other psychotic symptoms and 1 patient also had Capgras syndrome. These 7 cases series raise the possibility of an increase incidence of TV sign in patients with dementia during pandemia triggered by the rise in expo- sure to screen devices and a social isolation during this period.

These Are Not the Droids You Are Looking For: Mechanical Variant of Cotard’s Syndrome

Cotard's syndrome is a nihilistic delusion where the individual believes they are dead, partly dead, or replaced by an animal. The delusion that their body has been replaced by a purely inanimate azooic (but physical entity), such as a robot or a droid, has not hitherto been described. Case study: This 60-year-old, right-handed, female, with a past history of schizophrenia presented with complaints of depression, irritability, and anger. When confronted with commitment papers signed by her father, she denied their truthfulness, insisting that he had been replaced by an imposter. This belief persisted unabated, despite treatment with 20mg of haloperidol per day. Over time, she expressed the belief that she had been replaced by another person, whom she refused to identify. The following day she refused all food and water proclaiming that she had died and been replaced by a machine revealing, "I am not her. I am a robot." Soon thereafter she developed tremulousness, stiffness, and rigidity. After haloperidol was decreased and benztropine started, these parkinsonism symptoms subsided, but her delusions persisted. Abnormalities in physical examination: General: decreased blink frequency. Neurologic examination: Mental status examination: bradyphrenia, hypoverbal, blunted affect. Oriented ×2. Motor examination: bradykinetic, cogwheel rigidity in both upper extremities. Gait examination: slow shuffling gait, reduced bilateral arm swing. Cerebellar examination: resting tremor in both upper extremities at 3 cycles per second. Other: EEG: focal sharp transients in the left temporal region. MRI with and without contrast: normal. Toxicological, metabolic, endocrine screening: normal. This illustrated sequential presentations of three delusions of misidentification. Upon presentation, she exhibited Capgras syndrome, the delusional belief that a familiar person has been replaced by a double. The nidus for this may have been the discovery that her father had signed her commitment papers. This was followed by the belief she was a double of herself, which is the syndrome of Reverse Subjective Doubles. Finally, she manifested Cotard's syndrome in a previously undescribed manner, believing she had died and become a robot. Cotard's and Capgras syndromes are known to present sequentially rather than concurrently, whereas the patient presented concurrently with all three syndromes. Drug-induced parkinsonism may have made the patient subjectively feel stiff, which she interpreted as being rigid like a robot. She was bradykinetic, did not eat or drink, and had rigidity, suggesting that these were somatic manifestations of her underlying delusion of being a robot or alternatively, may have been the somatic nidus for the delusion. Those who present with Cotard's syndrome warrant evaluation for underlying medical conditions, serving as a substrate for this delusion. No funding.

Pellagra With Casal Necklace Causing Secondary Schizophrenia With Capgras Syndrome in a Homeless Man.

Pellagra With Casal Necklace Causing Secondary Schizophrenia With Capgras Syndrome in a Homeless Man.

Capgras Syndrome: Introduction, Overview, and Literature Review

Capgras Syndrome (CS) is a delusional disorder, one of the Delusional Misidentification Syndromes (DMSs), in which the patient believes that an ‘imposter’ has taken the place of one of their loved ones. This, at instances, results in violence and aggression towards the supposed imposter. In this paper, the aim is to see to it that the syndrome receives the attention that it deserves and that the most recent advances in the research related to the syndrome are illustrated in a concise manner.

Abstract- Poster

Abstract- Poster

Abstract- Poster

Introduction:Delusion of misidentifications are characterized by delusional belief that familiar person, objects, or self have been replaced or transformed. There are four common types like Capgras syndrome, Fregoli syndrome, Syndrome of subjective doubles and syndrome of intermetamorphosis. Another type of delusion of misidentification is mirrored self- misidentification, where the delusional belief is that one’s reflection in the mirror is misidentified as a stranger.Case report:A 83 years old male patient Mr. X, graduate, married, retired from his job, belonging to middle socio-economic status, hailing from urban background was accompanied to the OPD by his daughter. Informant had complaints of suspiciousness, abusing family members, abnormal behavior, and memory impairment since 6 months. Patient started suspecting that there is stranger whenever he looked into the mirrored or any other reflecting surfaces. Later he started suspecting that stranger was coming to meet his wife. Apart from this he also had memory disturbances. All the investigations were normal and he was started on Tab. Quetiapine -25mg and Tab. Donepezil -5mg.Discussion:The ability to recognize oneself in the mirror has a potential way of testing self-awareness, but it is not clearly known how the brain does it. Mirrored-self misidentification has rarely been described in the literature. Most of the reported patients have global dementia of the Alzheimer type, making it difficult to infer the anatomical basis of this disorder.Conclusion:The loss of the ability to recognize oneself in the mirror is evidence of a fundamental change in the sense of self and this may cause interpersonal problems as well. Managing such cases may be difficult and challenging.

A case of schizophrenia with Capgras delusion responded to donepezil.

A case of schizophrenia with Capgras delusion responded to donepezil.

Capgras syndrome in dementia with Lewy bodies: a possible association of severe cortical Lewy body pathology.

Capgras syndrome in dementia with Lewy bodies: a possible association of severe cortical Lewy body pathology.

What is Capgras delusion?

ABSTRACT Introduction Capgras delusion is sometimes defined as believing that close relatives have been replaced by strangers. But such replacement beliefs also occur in response to encountering an acquaintance, or the voice of a familiar person, or a pet, or some personal possession. All five scenarios involve believing something familiar has been replaced by something unfamiliar. Methods We evaluate the proposal that these five kinds of delusional belief should count as subtypes of the same delusion. Results Personally familiar stimuli activate the sympathetic nervous system (SNS) much more strongly than unfamiliar stimuli. In Capgras delusion, this difference is absent, prompting the delusional idea that a familiar person is actually a stranger. We suggest this absence of an effect of familiarity on SNS response will occur in all five scenarios and will prompt the idea that the familiar has been replaced by the unfamiliar. Conclusions We propose that: (a) all five scenarios be referred to as subtypes of Capgras delusion; (b) in all five, ideas about replacement are prompted by weakness of SNS responses to familiar stimuli; (c) this is insufficient to generate delusion. For a delusional idea to become a belief, a second factor (impaired hypothesis evaluation) must also be present.

Twilight and Me: A Soliloquy.

Dementia with Lewy bodies (DLB) is the third most frequent type of dementia. The range of symptoms it causes is quite broad and includes parkinsonism, autonomic dysfunction, cognitive deficits, visual and auditory hallucinations, dream disturbances, and other unusual manifestations such as "sense of presence," Capgras syndrome, and fluctuations in neurologic status. The author, an experienced behavioral neurologist and previous Continuum author, has been diagnosed with DLB and assumes the dual role of physician and patient. Each role provides a unique perspective. He discusses the importance of hope and fear in coping with the illness.

The Fractured Self: Exploring Selfhood in the Neuronovel The Echo Maker and the Neuromemoir

This paper will focus on two works: the neuronovel The Echo Maker (2006) by Richard Powers, a fictional account of Mark Schluter who suffers from Capgras Syndrome, that is, a rare neurological condition that results in the patient’s belief that their loved ones have been replaced with exact copies; and the neuromemoir Brain on Fire: My Month of Madness (2012) by Susannah Cahalan, which describes Cahalan’s experiences as she is diagnosed with anti-NMDA receptor encephalitis, a rare auto-immune disease. Both works have protagonists that suffer from a serious brain illness and must rely on their own perceptions, those of family and friends, and neuroscientific research in order to heal and create a more cohesive sense of self again. I argue that The Echo Maker and Brain on Fire complicate the perception of selfhood as the main character in each text can no longer trust their own perceptions and must instead weave together their fragmented personal experience, background from their social groups, and scientific explanations of their conditions to regain a sense of self. The narratives of The Echo Maker and Brain on Fire combine these different perspectives in an effort to regain a sense of selfhood that brain damage has fractured. While the result of the connections of millions of neurons is a smooth and linear perception of the self and the world around us, neuronarratives can complicate this process by revealing the divisions and occasional contradictions that occur in the combination.

Capgras syndrome

Capgras syndrome