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Sashank Prasad - One of the best experts on this subject based on the ideXlab platform.
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finding the imposter brain connectivity of lesions causing Delusional Misidentifications
Brain, 2017Co-Authors: Ryan R Darby, Sashank Prasad, Simon Laganiere, Alvaro Pascualleone, Michael D FoxAbstract:SEE MCKAY AND FURL DOI101093/AWW323 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Focal brain injury can sometimes lead to bizarre symptoms, such as the delusion that a family member has been replaced by an imposter (Capgras syndrome). How a single brain lesion could cause such a complex disorder is unclear, leading many to speculate that concurrent delirium, psychiatric disease, dementia, or a second lesion is required. Here we instead propose that Capgras and other Delusional Misidentification syndromes arise from single lesions at unique locations within the human brain connectome. This hypothesis is motivated by evidence that symptoms emerge from sites functionally connected to a lesion location, not just the lesion location itself. First, 17 cases of lesion-induced Delusional Misidentifications were identified and lesion locations were mapped to a common brain atlas. Second, lesion network mapping was used to identify brain regions functionally connected to the lesion locations. Third, regions involved in familiarity perception and belief evaluation, two processes thought to be abnormal in Delusional Misidentifications, were identified using meta-analyses of previous functional magnetic resonance imaging studies. We found that all 17 lesion locations were functionally connected to the left retrosplenial cortex, the region most activated in functional magnetic resonance imaging studies of familiarity. Similarly, 16 of 17 lesion locations were functionally connected to the right frontal cortex, the region most activated in functional magnetic resonance imaging studies of expectation violation, a component of belief evaluation. This connectivity pattern was highly specific for Delusional Misidentifications compared to four other lesion-induced neurological syndromes (P < 0.0001). Finally, 15 lesions causing other types of delusions were connected to expectation violation (P < 0.0001) but not familiarity regions, demonstrating specificity for delusion content. Our results provide potential neuroanatomical correlates for impaired familiarity perception and belief evaluation in patients with Delusional Misidentifications. More generally, we demonstrate a mechanism by which a single lesion can cause a complex neuropsychiatric syndrome based on that lesion's unique pattern of functional connectivity, without the need for pre-existing or hidden pathology.
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lesion related Delusional Misidentification syndromes a review of all reported cases p6 200
Neurology, 2016Co-Authors: Richard Darby, Sashank PrasadAbstract:Objective: To determine the clinical course, neuroanatomical localization, neuropsychological abnormalities, and Delusional content in patients with Delusional Misidentification syndromes (DMS) occurring after focal neurological injuries. Background: Delusional Misidentification Syndromes (DMS) describe persistent beliefs of hyper- or hypo-familiarity for meaningful objects in one9s environment. On the one hand, familiar persons or places can seem unfamiliar, perhaps even replaced by imposters; conversely, unfamiliar persons or places may seem familiar and in disguise. Despite growing recognition of DMS in the setting of focal neurological disease, a systematic evaluation of the clinical presentation, localization, and clinical outcomes in this disorder has been incomplete. Methods: We searched PubMed for all reported cases of DMS occurring in the setting of acute neurological injury through 2014. Results: Out of 507 papers identified, 61 cases with clinical and neuro-anatomical data met inclusion criteria. Delusions were recognized as hypo-familiar in 28 patients, hyper-familiar in 27 patients, and both hypo- and hyper-familiar in 6 patients. Recognition of the delusion after the time of injury was often delayed, typically up to 2 months. In most cases, the delusions spontaneously resolved or substantially improved over several months. Premorbid psychiatric disease, dementia, and advanced age were uncommon. Lesions were most frequently right-sided (90[percnt]) and frontal (63[percnt]). Cognitive impairments were common, including impaired memory (73[percnt]), executive dysfunction (52[percnt]), and visuospatial dysfunction (38[percnt]). Delusions were often not restricted to a particular category of objects, such as persons or places; 19 patients (29[percnt]) reported delusions across 2 or more categories. Conclusions: These findings provide a comprehensive analysis of the clinical course, localization, and Delusional features of DMS, providing insights into the potential mechanisms of these interesting disorders. Disclosure: Dr. Darby has nothing to disclose. Dr. Prasad has nothing to disclose.
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lesion related Delusional Misidentification syndromes a comprehensive review of reported cases
Journal of Neuropsychiatry and Clinical Neurosciences, 2016Co-Authors: Ryan R Darby, Sashank PrasadAbstract:Delusional Misidentification syndromes (DMSs) are persistent delusions of hyper- or hypofamiliarity for meaningful persons and places in one's environment. This study set to determine the clinical course, neuroanatomical localization, neuropsychological abnormalities, and Delusional content in patients with DMSs occurring after focal neurological injuries. Sixty-one patients were identified: 28 with hypofamiliar delusions, 27 with hyperfamiliar delusions, and, most surprisingly, six patients with both hypo- and hyperfamiliar delusions. Recognition is often delayed by months from the time of injury, and the delusions are self-limited. Patients with DMSs had right hemisphere (92%) injuries (specifically right frontal injuries in 63%), prominent memory impairment (73%), and multiple concurrent DMSs (29%).
Ryan R Darby - One of the best experts on this subject based on the ideXlab platform.
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finding the imposter brain connectivity of lesions causing Delusional Misidentifications
Brain, 2017Co-Authors: Ryan R Darby, Sashank Prasad, Simon Laganiere, Alvaro Pascualleone, Michael D FoxAbstract:SEE MCKAY AND FURL DOI101093/AWW323 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Focal brain injury can sometimes lead to bizarre symptoms, such as the delusion that a family member has been replaced by an imposter (Capgras syndrome). How a single brain lesion could cause such a complex disorder is unclear, leading many to speculate that concurrent delirium, psychiatric disease, dementia, or a second lesion is required. Here we instead propose that Capgras and other Delusional Misidentification syndromes arise from single lesions at unique locations within the human brain connectome. This hypothesis is motivated by evidence that symptoms emerge from sites functionally connected to a lesion location, not just the lesion location itself. First, 17 cases of lesion-induced Delusional Misidentifications were identified and lesion locations were mapped to a common brain atlas. Second, lesion network mapping was used to identify brain regions functionally connected to the lesion locations. Third, regions involved in familiarity perception and belief evaluation, two processes thought to be abnormal in Delusional Misidentifications, were identified using meta-analyses of previous functional magnetic resonance imaging studies. We found that all 17 lesion locations were functionally connected to the left retrosplenial cortex, the region most activated in functional magnetic resonance imaging studies of familiarity. Similarly, 16 of 17 lesion locations were functionally connected to the right frontal cortex, the region most activated in functional magnetic resonance imaging studies of expectation violation, a component of belief evaluation. This connectivity pattern was highly specific for Delusional Misidentifications compared to four other lesion-induced neurological syndromes (P < 0.0001). Finally, 15 lesions causing other types of delusions were connected to expectation violation (P < 0.0001) but not familiarity regions, demonstrating specificity for delusion content. Our results provide potential neuroanatomical correlates for impaired familiarity perception and belief evaluation in patients with Delusional Misidentifications. More generally, we demonstrate a mechanism by which a single lesion can cause a complex neuropsychiatric syndrome based on that lesion's unique pattern of functional connectivity, without the need for pre-existing or hidden pathology.
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lesion related Delusional Misidentification syndromes a comprehensive review of reported cases
Journal of Neuropsychiatry and Clinical Neurosciences, 2016Co-Authors: Ryan R Darby, Sashank PrasadAbstract:Delusional Misidentification syndromes (DMSs) are persistent delusions of hyper- or hypofamiliarity for meaningful persons and places in one's environment. This study set to determine the clinical course, neuroanatomical localization, neuropsychological abnormalities, and Delusional content in patients with DMSs occurring after focal neurological injuries. Sixty-one patients were identified: 28 with hypofamiliar delusions, 27 with hyperfamiliar delusions, and, most surprisingly, six patients with both hypo- and hyperfamiliar delusions. Recognition is often delayed by months from the time of injury, and the delusions are self-limited. Patients with DMSs had right hemisphere (92%) injuries (specifically right frontal injuries in 63%), prominent memory impairment (73%), and multiple concurrent DMSs (29%).
Cordeiro Quirino - One of the best experts on this subject based on the ideXlab platform.
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Coexistence of Capgras and Frégoli syndromes associated to frontotemporal volume reduction and cerebral white matter hyperintensities
Faculdade de Medicina da Universidade de São Paulo, 2009Co-Authors: Turkiewicz Gizela, Zanetti, Marcus Vinicius, Zung Stevin, Cordeiro QuirinoAbstract:CONTEXTO: Transtornos delirantes de identificação são condições nas quais os pacientes identificam de maneira patologicamente equivocada pessoas, lugares, objetos ou eventos. Esses transtornos têm sido categorizados em quatro diferentes subtipos: Capgras, Frégoli, intermetamorfose e síndrome do duplo subjetivo. Tais síndromes podem estar presentes em diferentes transtornos psiquiátricos, como esquizofrenia e transtornos do humor, bem como em diferentes doenças neurológicas, como Alzheimer, Parkinson, lesões cerebrais traumáticas ou vasculares. OBJETIVOS: Descrever e discutir um caso de coexistência entre as síndromes de Capgras e Frégoli em uma paciente com esquizofrenia paranoide e com alterações cerebrais. MÉTODOS: Entrevista psiquiátrica e ressonância magnética de crânio. RESULTADOS: A paciente apresentava hiperintensidades periventriculares em aquisição flair e de substância branca subcortical concentradas principalmente na região frontotemporal direita, bem como perda do volume da região frontotemporal bilateral. DISCUSSÃO: As alterações descritas podem representar substrato orgânico das síndromes dos transtornos delirantes de identificação. Os delírios nas síndromes de Capgras e Frégoli podem ocorrer como resultado de uma desconexão têmporo-límbica-frontal direita, resultando em uma impossibilidade de associar memórias prévias a novas informações, levando consequentemente a alterações na capacidade de reconhecimento. Ademais, uma perda do volume de tais regiões cerebrais também pode desempenhar papel importante no desenvolvimento de tais síndromes delirantes de identificação.BACKGROUND: Delusional Misidentification syndromes are conditions in which the patients pathologically misidentify people, places, objects or events. They have been categorized in four subtypes: Capgras, Frégoli, intermetamorphosis and subjective double syndromes. Such syndromes may be present in patients with psychiatric disorders such as schizophrenia and mood disorders, and with neurological diseases such as Alzheimer, Parkinson and brain injury (trauma, vascular). OBJECTIVES: To describe and discuss a case of coexistent between Capgras and Frégoli syndromes in a female patient with paranoid schizophrenia and brain MRI findings. METHODS: Psychiatric interview and brain MRI scanning. RESULTS: The patient presented structural magnetic resonance imaging periventricular and subcortical white matter hyperintensities on flair images mainly concentrated in the right frontotemporal region and bilateral frontotemporal volume loss. DISCUSSION: The described neuroimaging findings may represent an organic substrate to the Delusional Misidentification syndromes of the present case. The Delusional symptoms in Capgras and Frégoli syndromes could be the result of a right temporolimbic-frontal disconnection which results in impossibility to associate previous memories to new information and consequently misidentifying symptoms. Moreover a volume loss of such cerebral regions, as observed in the present case, may also play a significant role in the development of Delusional Misidentification syndromes
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Coexistência das síndromes de Capgras e Frégoli associadas à redução de volume frontotemporal e hiperintensidades em substância branca cerebral
Universidade de São Paulo. Faculdade de Medicina. Instituto de Psiquiatria, 2009Co-Authors: Turkiewicz Gizela, Zanetti, Marcus Vinicius, Zung Stevin, Cordeiro QuirinoAbstract:BACKGROUND: Delusional Misidentification syndromes are conditions in which the patients pathologically misidentify people, places, objects or events. They have been categorized in four subtypes: Capgras, Frégoli, intermetamorphosis and subjective double syndromes. Such syndromes may be present in patients with psychiatric disorders such as schizophrenia and mood disorders, and with neurological diseases such as Alzheimer, Parkinson and brain injury (trauma, vascular). OBJECTIVES: To describe and discuss a case of coexistent between Capgras and Frégoli syndromes in a female patient with paranoid schizophrenia and brain MRI findings. METHODS: Psychiatric interview and brain MRI scanning. RESULTS: The patient presented structural magnetic resonance imaging periventricular and subcortical white matter hyperintensities on flair images mainly concentrated in the right frontotemporal region and bilateral frontotemporal volume loss. DISCUSSION: The described neuroimaging findings may represent an organic substrate to the Delusional Misidentification syndromes of the present case. The Delusional symptoms in Capgras and Frégoli syndromes could be the result of a right temporolimbic-frontal disconnection which results in impossibility to associate previous memories to new information and consequently misidentifying symptoms. Moreover a volume loss of such cerebral regions, as observed in the present case, may also play a significant role in the development of Delusional Misidentification syndromes.CONTEXTO: Transtornos delirantes de identificação são condições nas quais os pacientes identificam de maneira patologicamente equivocada pessoas, lugares, objetos ou eventos. Esses transtornos têm sido categorizados em quatro diferentes subtipos: Capgras, Frégoli, intermetamorfose e síndrome do duplo subjetivo. Tais síndromes podem estar presentes em diferentes transtornos psiquiátricos, como esquizofrenia e transtornos do humor, bem como em diferentes doenças neurológicas, como Alzheimer, Parkinson, lesões cerebrais traumáticas ou vasculares. OBJETIVOS: Descrever e discutir um caso de coexistência entre as síndromes de Capgras e Frégoli em uma paciente com esquizofrenia paranoide e com alterações cerebrais. MÉTODOS: Entrevista psiquiátrica e ressonância magnética de crânio. RESULTADOS: A paciente apresentava hiperintensidades periventriculares em aquisição flair e de substância branca subcortical concentradas principalmente na região frontotemporal direita, bem como perda do volume da região frontotemporal bilateral. DISCUSSÃO: As alterações descritas podem representar substrato orgânico das síndromes dos transtornos delirantes de identificação. Os delírios nas síndromes de Capgras e Frégoli podem ocorrer como resultado de uma desconexão têmporo-límbica-frontal direita, resultando em uma impossibilidade de associar memórias prévias a novas informações, levando consequentemente a alterações na capacidade de reconhecimento. Ademais, uma perda do volume de tais regiões cerebrais também pode desempenhar papel importante no desenvolvimento de tais síndromes delirantes de identificação
Arno Villringer - One of the best experts on this subject based on the ideXlab platform.
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capgras delusion in posterior cortical atrophy a quantitative multimodal imaging single case study
Frontiers in Aging Neuroscience, 2020Co-Authors: Franziska Albrecht, Tommaso Ballarini, Dominique Leuthold, Angela Legler, Simone Hartwig, Matthias L Schroeter, Solveig Tiepolt, Arno VillringerAbstract:Although Alzheimer's disease presents homogeneous histopathology, it causes several clinical phenotypes depending on brain regions involved. Beside the most abundant memory variant, several atypical variants exist. Among them posterior cortical atrophy (PCA) is associated with severe visuospatial/visuoperceptual deficits in the absence of significant primary ocular disease. Here, we report for the first time a case of Capgras delusion-a Delusional Misidentification syndrome, where patients think that familiar persons are replaced by identical "doubles" or an impostor-in a patient with PCA. The 57-year-old female patient was diagnosed with PCA and developed Capgras delusion 8 years after first symptoms. The patient did not recognize her husband, misidentified him as a stranger, and perceived him as a threat. Such Misidentifications did not happen for other persons. Events could be interrupted by reassuring the husband's identity by the patient's female friend or children. We applied in-depth multimodal neuroimaging phenotyping and used single-subject voxel-based morphometry to identify atrophy changes specifically related to the development of the Capgras delusion. The latter, based on structural T1 magnetic resonance imaging, revealed progressive gray matter volume decline in occipital and temporoparietal areas, involving more the right than the left hemisphere, especially at the beginning. Correspondingly, the right fusiform gyrus was already affected by atrophy at baseline, whereas the left fusiform gyrus became involved in the further disease course. At baseline, glucose hypometabolism as measured by positron emission tomography (PET) with F18-fluorodesoxyglucose (FDG-PET) was evident in the parietooccipital cortex, more pronounced right-sided, and in the right frontotemporal cortex. Amyloid accumulation as assessed by PET with F18-florbetaben was found in the gray matter of the neocortex indicating underlying Alzheimer's disease. Appearance of the Capgras delusion was related to atrophy in the right posterior cingulate gyrus/precuneus, as well as right middle frontal gyrus/frontal eye field, supporting right frontal areas as particularly relevant for Capgras delusion. Atrophy in these regions respectively might affect the default mode and dorsal attention networks as shown by meta-analytical co-activation and resting state functional connectivity analyses. This case elucidates the brain-behavior relationship in PCA and Capgras delusion.
Turkiewicz Gizela - One of the best experts on this subject based on the ideXlab platform.
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Coexistence of Capgras and Frégoli syndromes associated to frontotemporal volume reduction and cerebral white matter hyperintensities
Faculdade de Medicina da Universidade de São Paulo, 2009Co-Authors: Turkiewicz Gizela, Zanetti, Marcus Vinicius, Zung Stevin, Cordeiro QuirinoAbstract:CONTEXTO: Transtornos delirantes de identificação são condições nas quais os pacientes identificam de maneira patologicamente equivocada pessoas, lugares, objetos ou eventos. Esses transtornos têm sido categorizados em quatro diferentes subtipos: Capgras, Frégoli, intermetamorfose e síndrome do duplo subjetivo. Tais síndromes podem estar presentes em diferentes transtornos psiquiátricos, como esquizofrenia e transtornos do humor, bem como em diferentes doenças neurológicas, como Alzheimer, Parkinson, lesões cerebrais traumáticas ou vasculares. OBJETIVOS: Descrever e discutir um caso de coexistência entre as síndromes de Capgras e Frégoli em uma paciente com esquizofrenia paranoide e com alterações cerebrais. MÉTODOS: Entrevista psiquiátrica e ressonância magnética de crânio. RESULTADOS: A paciente apresentava hiperintensidades periventriculares em aquisição flair e de substância branca subcortical concentradas principalmente na região frontotemporal direita, bem como perda do volume da região frontotemporal bilateral. DISCUSSÃO: As alterações descritas podem representar substrato orgânico das síndromes dos transtornos delirantes de identificação. Os delírios nas síndromes de Capgras e Frégoli podem ocorrer como resultado de uma desconexão têmporo-límbica-frontal direita, resultando em uma impossibilidade de associar memórias prévias a novas informações, levando consequentemente a alterações na capacidade de reconhecimento. Ademais, uma perda do volume de tais regiões cerebrais também pode desempenhar papel importante no desenvolvimento de tais síndromes delirantes de identificação.BACKGROUND: Delusional Misidentification syndromes are conditions in which the patients pathologically misidentify people, places, objects or events. They have been categorized in four subtypes: Capgras, Frégoli, intermetamorphosis and subjective double syndromes. Such syndromes may be present in patients with psychiatric disorders such as schizophrenia and mood disorders, and with neurological diseases such as Alzheimer, Parkinson and brain injury (trauma, vascular). OBJECTIVES: To describe and discuss a case of coexistent between Capgras and Frégoli syndromes in a female patient with paranoid schizophrenia and brain MRI findings. METHODS: Psychiatric interview and brain MRI scanning. RESULTS: The patient presented structural magnetic resonance imaging periventricular and subcortical white matter hyperintensities on flair images mainly concentrated in the right frontotemporal region and bilateral frontotemporal volume loss. DISCUSSION: The described neuroimaging findings may represent an organic substrate to the Delusional Misidentification syndromes of the present case. The Delusional symptoms in Capgras and Frégoli syndromes could be the result of a right temporolimbic-frontal disconnection which results in impossibility to associate previous memories to new information and consequently misidentifying symptoms. Moreover a volume loss of such cerebral regions, as observed in the present case, may also play a significant role in the development of Delusional Misidentification syndromes
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Coexistência das síndromes de Capgras e Frégoli associadas à redução de volume frontotemporal e hiperintensidades em substância branca cerebral
Universidade de São Paulo. Faculdade de Medicina. Instituto de Psiquiatria, 2009Co-Authors: Turkiewicz Gizela, Zanetti, Marcus Vinicius, Zung Stevin, Cordeiro QuirinoAbstract:BACKGROUND: Delusional Misidentification syndromes are conditions in which the patients pathologically misidentify people, places, objects or events. They have been categorized in four subtypes: Capgras, Frégoli, intermetamorphosis and subjective double syndromes. Such syndromes may be present in patients with psychiatric disorders such as schizophrenia and mood disorders, and with neurological diseases such as Alzheimer, Parkinson and brain injury (trauma, vascular). OBJECTIVES: To describe and discuss a case of coexistent between Capgras and Frégoli syndromes in a female patient with paranoid schizophrenia and brain MRI findings. METHODS: Psychiatric interview and brain MRI scanning. RESULTS: The patient presented structural magnetic resonance imaging periventricular and subcortical white matter hyperintensities on flair images mainly concentrated in the right frontotemporal region and bilateral frontotemporal volume loss. DISCUSSION: The described neuroimaging findings may represent an organic substrate to the Delusional Misidentification syndromes of the present case. The Delusional symptoms in Capgras and Frégoli syndromes could be the result of a right temporolimbic-frontal disconnection which results in impossibility to associate previous memories to new information and consequently misidentifying symptoms. Moreover a volume loss of such cerebral regions, as observed in the present case, may also play a significant role in the development of Delusional Misidentification syndromes.CONTEXTO: Transtornos delirantes de identificação são condições nas quais os pacientes identificam de maneira patologicamente equivocada pessoas, lugares, objetos ou eventos. Esses transtornos têm sido categorizados em quatro diferentes subtipos: Capgras, Frégoli, intermetamorfose e síndrome do duplo subjetivo. Tais síndromes podem estar presentes em diferentes transtornos psiquiátricos, como esquizofrenia e transtornos do humor, bem como em diferentes doenças neurológicas, como Alzheimer, Parkinson, lesões cerebrais traumáticas ou vasculares. OBJETIVOS: Descrever e discutir um caso de coexistência entre as síndromes de Capgras e Frégoli em uma paciente com esquizofrenia paranoide e com alterações cerebrais. MÉTODOS: Entrevista psiquiátrica e ressonância magnética de crânio. RESULTADOS: A paciente apresentava hiperintensidades periventriculares em aquisição flair e de substância branca subcortical concentradas principalmente na região frontotemporal direita, bem como perda do volume da região frontotemporal bilateral. DISCUSSÃO: As alterações descritas podem representar substrato orgânico das síndromes dos transtornos delirantes de identificação. Os delírios nas síndromes de Capgras e Frégoli podem ocorrer como resultado de uma desconexão têmporo-límbica-frontal direita, resultando em uma impossibilidade de associar memórias prévias a novas informações, levando consequentemente a alterações na capacidade de reconhecimento. Ademais, uma perda do volume de tais regiões cerebrais também pode desempenhar papel importante no desenvolvimento de tais síndromes delirantes de identificação