Delusional misidentification

The neuropsychology and neuroanatomy of reduplicative paramnesia

Reduplicative paramnesia refers to the delusional belief that there are identical places in different locations. In this case-control study we investigated the clinical, phenomenological, neuropsychological and neuroanatomical data of eleven patients with reduplicative paramnesia and compared them against a control group of eleven patients with severe spatial disorientation without signs of reduplicative paramnesia. We show that most patients with reduplicative paramnesia report that a current place is reduplicated and/or relocated to an other familiar place. Patients with reduplicative paramnesia show a higher prevalence of deficits in the executive functions compared to the control patients, while mnestic and visuo-spatial deficits were both frequent in patients with reduplicative paramnesia and the control group. Patients with reduplicative paramnesia mostly suffer from right hemispheric lesions with a maximal overlap in the dorsolateral prefrontal cortex. Using lesion network mapping we show that lesions causing reduplicative paramnesia are connected to bilateral anterior insula and the right cingulate cortex. We argue that patients with reduplicative paramnesia fail to integrate the actual context with visuo-spatial memories and personal relevant emotional information due to a disruption of the neural network within the anterior temporal lobe, the cingulate cortex and the anterior insula. Also patients with reduplicative paramnesia are not able to resolve this conflict due to the lesion of the dorsolateral prefrontal cortex and executive dysfunction.

Déjà vécu with recollective confabulation: an unusual presentation of Alzheimer's disease

A man in his 80s presented with gradual onset of a persistent and delusion-like perception that novel encounters are repetitions of previous experiences. Within 2 years of symptom onset, he had impaired verbal memory and executive dysfunction on neuropsychological assessment. Cerebrospinal fluid core Alzheimer's disease (AD) biomarkers analysis supported probable AD. Generalised and left temporal atrophy was seen on MRI of the brain. Neurological fludeoxyglucose-positron emission tomography (PET)/CT showed left temporal and bilateral frontal lobe hypometabolism. His presenting symptom is known as déjà vécu with recollective confabulation, a rare phenomenon associated with AD and other neurodegenerative disorders. While several potential mechanisms have been previously proposed, the fludeoxyglucose-PET/CT hypometabolism in the temporal and frontal lobes in this case suggests dual deficits in recognition memory and metacognition may be culprit mechanisms. Although uncommon, déjà vécu with recollective confabulation is a fascinating phenomenon that can provide a unique insight into memory and delusional processes in dementia.

Analysis of clinical characteristics of mirror and TV signs in Alzheimer's disease and dementia with Lewy bodies

OBJECTIVE

This study explored the clinical features of dementia with Lewy bodies (DLB) and Alzheimer's disease (AD) and analyzed the differences in neurologic syndromes, including mirror and TV signs, between different groups.

METHODS

Patients with AD and DLB (325 and 115, respectively) hospitalized in our institution were enrolled. We compared psychiatric symptoms and neurologic syndromes between the DLB and AD groups and within each subgroup, including the mild-moderate and severe subgroups.

RESULTS

The prevalence rates of visual hallucination, parkinsonism, rapid eye movement sleep behavior disorder, depression, delusion, and the Pisa sign were significantly higher in the DLB group than in the AD group. Furthermore, within the mild-moderate subgroup, the mirror sign and Pisa sign prevalence rates were significantly higher in the DLB group than in the AD group. In the severe subgroup, no significant difference was found in any neurologic sign between the DLB and AD groups.

CONCLUSION

Mirror and TV signs are rare and often disregarded because they are not usually invoked during routine inpatient or outpatient interviews. According to our findings, the mirror sign is uncommon in early AD patients but common in early DLB patients and should receive increased attention.

Transforming Social Perspectives with Cognitive Maps

Growing evidence suggests that cognitive maps represent relations between social knowledge similar to how spatial locations are represented in an environment. Notably, the extant human medial temporal lobe literature assumes associations between social stimuli follow a linear associative mapping from an egocentric viewpoint to a cognitive map. Yet, this form of associative social memory doesn't account for a core phenomenon of social interactions in which social knowledge learned via comparisons to the self, other individuals, or social networks are assimilated within a single frame of reference. We argue that hippocampal-entorhinal coordinate transformations, known to integrate egocentric and allocentric spatial cues, inform social perspective switching between the self and others. We present evidence that the hippocampal formation helps inform social interactions by relating self versus other social attribute comparisons to society in general, which can afford rapid and flexible assimilation of knowledge about the relationship between the self and social networks of varying proximities. We conclude by discussing the ramifications of cognitive maps in aiding this social perspective transformation process in states of health and disease.

THE LOSS OF FAMILIARITY: A CASE STUDY OF THE COMORBIDITIES OF CAPGRAS AND FREGOLI

This case study describes the coexistence of Capgras and Fregoli-type delusions in a 51-year-old woman. The patient reported that her children were kidnapped and replaced with doubles. She claims that several customers at her shop are her real children. Neuropsychological assessment revealed severe defects in social cognition and an increased number of perseveration responses in the self-directed signaling task. We propose that the latter finding is a measure of the familiarity phenomenon and may be associated with hypofunction in the left retrosplenial region. SPECT-CT confirmed a pattern of hypoperfusion in the retrosplenial, posterior cingulate, and prefrontal cortex.

The Neurological Asymmetry of Self-Face Recognition

While the desire to uncover the neural correlates of consciousness has taken numerous directions, self-face recognition has been a constant in attempts to isolate aspects of self-awareness. The neuroimaging revolution of the 1990s brought about systematic attempts to isolate the underlying neural basis of self-face recognition. These studies, including some of the first fMRI (functional magnetic resonance imaging) examinations, revealed a right-hemisphere bias for self-face recognition in a diverse set of regions including the insula, the dorsal frontal lobe, the temporal parietal junction, and the medial temporal cortex. In this systematic review, we provide confirmation of these data (which are correlational) which were provided by TMS (transcranial magnetic stimulation) and patients in which direct inhibition or ablation of right-hemisphere regions leads to a disruption or absence of self-face recognition. These data are consistent with a number of theories including a right-hemisphere dominance for self-awareness and/or a right-hemisphere specialization for identifying significant social relationships, including to oneself.

A Rare Report of Clinical Lycanthropy in Obsessive-Compulsive and Related Disorders

Lycanthropy is a rare variant of a delusional misidentification syndrome specifically reverse inter-metamorphosis where patients believe that they are experiencing transformation or have transformed into an animal. A case report of this phenomenon is discussed. We report the lycanthropy phenomenon of a 25-year-old male who believed himself to be transformed into a buffalo after bestiality along with developing obsessive-compulsive features. A case report along with a literature review forms the basis of discussion. Clinical lycanthropy has been reported with various neuropsychiatric conditions including primary psychotic and affective conditions, drug intoxication and withdrawal, cerebrovascular disease, traumatic brain injury, dementia, delirium, and seizures, but its association in the context of obsessive-compulsive and related disorders (OCRDs) is a very rare finding. A differential of OCRD should be given due importance and managed accordingly when dealing with lycanthropy, which may help in early identification and management. 

Do Process-1 simulations generate the epistemic feelings that drive Process-2 decision making?

We apply previously developed Chu space and Channel Theory methods, focusing on the construction of Cone-Cocone Diagrams (CCCDs), to study the role of epistemic feelings, particularly feelings of confidence, in dual process models of problem solving. We specifically consider "Bayesian brain" models of probabilistic inference within a global neuronal workspace architecture. We develop a formal representation of Process-1 problem solving in which a solution is reached if and only if a CCCD is completed. We show that in this representation, Process-2 problem solving can be represented as multiply iterated Process-1 problem solving and has the same formal solution conditions. We then model the generation of explicit, reportable subjective probabilities from implicit, experienced confidence as a simulation-based, reverse engineering process and show that this process can also be modeled as a CCCD construction.

Prevalence and Clinical Implications of the Mirror and TV Signs in Advanced Alzheimer's Disease and Dementia with Lewy Bodies

Objective

To explore the prevalence and clinical implications of the mirror and TV signs in the moderate to advanced stages of Alzheimer's disease (AD) and dementia with Lewy bodies (DLB).

Methods

We retrospectively examined the prevalence of clinical and psychiatric symptoms including the mirror and TV signs in 200 subjects with AD and 200 with DLB and evaluated the relationships among the symptoms.

Results

The mirror sign was found in 3.0% of AD and 4.5% of DLB subjects. The TV sign was found in 1.5% of AD and 4.0% of DLB subjects. The prevalence of the mirror and TV signs was not significantly different between the AD and DLB groups. Visual hallucination, visual illusion, misidentification of person, and sleep talking were significantly more frequent in DLB than in AD subjects. The mirror sign was significantly associated with lower Mini-Mental State Examination scores, whereas the TV sign was significantly associated with the misidentification of person.

Conclusions

Both the mirror and TV signs were rare even in the moderate to advanced stages of AD and DLB. The mirror sign may be independent from other delusional misidentification syndromes (DMSs). Being associated mainly with global cognitive decline, the mirror sign is unlikely attributed to any specific cognitive impairment or the dysfunction of localized brain areas. In contrast, the TV sign was significantly more often coexistent with the misidentification of person, suggesting that the TV sign may partly share common neuropsychological mechanisms with DMSs.

Development of the functional connectivity of the frontoparietal mirror neuron network in preschool Children: An investigation under resting state

Previous task-related imaging studies in adults have demonstrated that there is a frontoparietal mirror neuron system (MNS) that preferentially engages in self-recognition. However, the development of the MNS during preschool (age 3-5 years) has not been thoroughly examined. In this study, we investigated the development of the MNS by examining the correlations in spontaneous fluctuations of the functional magnetic resonance imaging (fMRI) blood oxygen level-dependent (BOLD) signal in healthy, 3-5-year-old preschool children (n = 30, 15 in each group). Using a ROI-based (inferior frontal gyrus) functional connectivity analysis, we identified a right lateralized MNS during rest in both groups with a positive correlation between the inferior frontal gyrus and inferior parietal lobule. A significant increase in the functional connectivity of the MNS was observed in the older group. Our results suggest that the spontaneous functional connectivity of the MNS is shaped at as early as 3 years of age and undergoes age-related development within the preschool period.

Understanding misidentification syndromes using the integrative memory model

Misidentification syndromes occur commonly in neuropsychiatric practice and can be explained through aberrant integration of recollection and familiarity, in keeping with a dysfunction at the level of the attributional system in the new integrative memory model. We examine neuroimaging findings associated with Fregoli and Capgras syndromes and compare these with the proposed neural substrate of the integrative memory model supporting the core and attribution functions.

Psicopatologia em O duplo de Dostoiévski

O duplo aborda o tema da duplicidade do eu. Traz na narrativa descrições psicopatológicas da síndrome de duplos subjetivos e da esquizofrenia numa época em que essas condições ainda não tinham sido descritas. Este artigo situa a obra literária na história da psiquiatria, ressaltando o pioneirismo de Fiodor Dostoiévski, sua forma de narrar o tema e como conseguiu tratar o tema de forma clínica.

An unusual delusion of duplication in a patient affected by Dementia with Lewy bodies

Background

Dementia with Lewy bodies (DLB) is the second most frequent diagnosis of progressive degenerative dementia in older people. Delusions are common features in DLB and, among them, Capgras syndrome represents the most frequent disturbance, characterized by the recurrent and transient belief that a familiar person, often a close family member or caregiver, has been replaced by an identical-looking imposter. However, other delusional conditions near to misidentification syndromes can occur in DLB patients and may represent a major psychiatric disorder, although rarely studied systematically.

Case presentation

We reported on a female patient affected by DLB who presented with an unusual delusion of duplication. Referring to the female professional caregiver engaged by her relatives for her care, the patient constantly described the presence of two different female persons, with a disorder framed in the context of a delusion of duplication.

A brain 99Tc-hexamethylpropyleneamineoxime SPECT was performed showing moderate hypoperfusion in both occipital lobes, and associated with marked decreased perfusion in parieto-fronto-temporal lobes bilaterally.

Conclusions

An occipital hypoperfusion was identified, although in association with a marked global decrease of perfusion in the remaining lobes. The role of posterior lobes is certainly important in all misidentification syndromes where a natural dissociation between recognition and identification is present. Moreover, the concomitant presence of severe attentional and executive deficits evocative for a frontal syndrome and the marked global decrease of perfusion in the remaining lobes at the SPECT scan also suggest a possible dysfunction in an abnormal connectivity between anterior and posterior areas.

Electronic supplementary material

The online version of this article (doi:10.1186/s12883-017-0842-1) contains supplementary material, which is available to authorized users.

Implicit Recognition of Familiar and Unfamiliar Faces in Schizophrenia: A Study of the Skin Conductance Response in Familiarity Disorders

OBJECTIVE

Familiarity is a subjective sensation that contributes to person recognition. This process is described as an emotion-based memory-trace of previous meetings and could be disrupted in schizophrenia. Consequently, familiarity disorders could be involved in the impaired social interactions observed in patients with schizophrenia. Previous studies have primarily focused on famous people recognition. Our aim was to identify underlying features, such as emotional disturbances, that may contribute to familiarity disorders in schizophrenia. We hypothesize that patients with familiarity disorders will exhibit a lack of familiarity that could be detected by a flattened skin conductance response (SCR).

METHOD

The SCR was recorded to test the hypothesis that emotional reactivity disturbances occur in patients with schizophrenia during the categorization of specific familiar, famous and unknown faces as male or female. Forty-eight subjects were divided into the following 3 matched groups with 16 subjects per group: control subjects, schizophrenic people with familiarity disorder, and schizophrenic people without familiarity disorders.

RESULTS

Emotional arousal is reflected by the skin conductance measures. The control subjects and the patients without familiarity disorders experienced a differential emotional response to the specific familiar faces compared with that to the unknown faces. Nevertheless, overall, the schizophrenic patients without familiarity disorders showed a weaker response across conditions compared with the control subjects. In contrast, the patients with familiarity disorders did not show any significant differences in their emotional response to the faces, regardless of the condition.

CONCLUSION

Only patients with familiarity disorders fail to exhibit a difference in emotional response between familiar and non-familiar faces. These patients likely emotionally process familiar faces similarly to unknown faces. Hence, the lower feelings of familiarity in schizophrenia may be a premise enabling the emergence of familiarity disorders.

A Case of Reduplicative Paramnesia for Home

We present the case of a high-functioning 88-year-old woman who suddenly developed the persistent and disturbing belief that her home of 40 years was not genuine, but rather an accurate replica. Her episode was probably caused by a small stroke that left her with this single extremely specific deficit. We describe the patient in detail and link to a video interview of her 3 months after the onset of the delusion, eloquently describing her experience. We summarize some of the many reports and discussions of our patient's delusion, reduplicative paramnesia, as well as other delusional misidentification syndromes.

Self-representation in delusional misidentification and confabulated "others"

In some instances the ostensibly false narratives produced by patients with delusional misidentification syndromes (DMS) or confabulation may - unbeknownst to the patient - contain some authentic self-referential information. In this review, extracted from a video library or verbatim transcripts of approximately 50 clinical cases with either delusional misidentification or some variety of confabulation, we identified four cases (Feinberg, 2001, 2009, 2010; Feinberg & Shapiro, 1989) with either DMS for persons or confabulations about "phantom" persons, who showed prominent "self-referential" (SR) narratives. The presence of self-referential narratives was judged by: 1) the misidentification or confabulation was generally consistent and repeatable, e.g., the narrative was repeated on more than one occasion and not variably "provoked," 2) the content of the delusional misidentifications or confabulations were facts, feelings, or motivations that were true of the patients themselves either by history obtained from collateral sources (medical records, family, friends, etc.) or by admission by the patients themselves, but were attributed to a "double" of confabulated person, 3) these facts or feelings attributed to the "double" or confabulated "other" were either denied by the patients or admitted but also attributed to the "other." For purposes of comparison we also selected from the original group of 50 patients four "comparison" cases with delusional misidentification for persons and/or confabulation who based on these same criteria for self-referential material, were judged not to show self-referential (SR) aspects (Comparison cases 1-4). The neuroanatomy and neurocognitive features of these cases are reviewed and compared, the possible role of psychological defense in the self-referential cases is considered, and a model that integrates the neuroanatomical, neuropsychological and dynamic psychological aspects of these self-related disorders is offered. We propose that an appreciation of these self-related productions could have significant clinical and therapeutic implications.

Some Unusual Neuropsychological Syndromes: Somatoparaphrenia, Akinetopsia, Reduplicative Paramnesia, Autotopagnosia

Some unusual neuropsychological syndromes are rarely reported in the neuropsychological literature. This paper presents a review of four of these unusual clinical syndromes: (1) somatoparaphrenia (delusional belief in which a patient states that the limb contralateral to a brain pathology, does not belong to him/her); (2) akinetopsia (cortical syndrome in which patient losses the ability to perceive visual motion); (3) reduplicative paramnesia (believe that a familiar place, person, object, or body part has been duplicated); and (4) autotopagnosia (disturbance of body schema involving the loss of ability to localize, recognize, or identify the specific parts of one's body). It is concluded that regardless of their rarity, it is fundamental to take them into consideration in order to understand how the brain organizes cognition; their understanding is also crucial in the clinical analysis of patients with brain pathologies.

History repeating itself: Arnaud's case of pathological déjà vu

We present a translation of Arnaud's (1896) case report of Patient Louis, a case he describes as having a pathological form of déjà vu. Louis has the delusional belief that the present moment is a repetition of an exact same previous event. Arnaud's paper is critical for two reasons. Firstly, it is amongst the first articles in the scientific literature to describe the déjà vu experience using the term 'déjà vu'. Secondly, the case report of someone with delusional and persistent déjà vu, anticipates recently reported cases with similar symptoms, which are beginning to gain interest as a particular form of memory disorder. We offer a contemporary analysis of Louis and conclude that, whilst the article was critical in the development of déjà vu as a scientific concern, Louis's distorted memory is not best described as déjà vu, but rather as a form of reduplicative paramnesia described as recollective confabulation.

A Case of Capgras Syndrome Related to Hypothyroidism

Hypothyroidism is commonly associated with a variety of psychiatric conditions, most commonly depression and cognitive impairment, but up to 5% to 15% of symptomatically hypothyroid patients may develop a nonaffective psychosis, classically referred to as "myxedema madness." We report the case of a woman who developed Capgras syndrome in the context of hypothyroidism, and whose psychosis rapidly resolved with levothyroxine supplementation. To date, very few cases of Capgras syndrome related to hypothyroidism have been reported. The pathophysiology of this condition remains unclear but it may be related to global cerebral hypometabolism or possibly to increased cerebral dopamine. Given the robust response of "myxedema madness" to thyroid replacement, psychiatrists should remain vigilant for covert hypothyroidism in patients with psychosis and atypical histories or presentations.

Cotard and Capgras syndrome after ischemic stroke

Capgras and Cotard are delusional misidentification syndromes characterized by delusions about oneself, others, places, and objects. To date, there are few cases of comorbidity of both syndromes. We describe a case of aphasic stroke patient affected by cerebral ischemia localized in right temporoparietal region. The patient showed a typical clinical picture of delusional disorder attributable, through psychological assessment, to comorbidity of both Capgras and Cotard syndromes.

Lesion-symptom mapping of self-prioritization in explicit face categorization: distinguishing hypo- and hyper-self-biases

People make faster familiarity decisions for their own face compared with a familiar other. Lesion studies diverge on whether this self-face prioritization (SFP) effect is associated with functional processes isolated in the left or right hemispheres. To assess both decreases (hypo-) and increases (hyper-) in SFP after brain lesion, we asked patients with chronic deficits to perform familiarity judgments to images of their own face, a familiar other, or unfamiliar faces. Of 30 patients, 7 showed hypo- and 6 showed hyper-self-bias effects, comparing responses with their own faces versus responses with a familiar other. Hyper-self-bias correlated with reduced executive control function and, at a neural level, this was associated with lesions to the left prefrontal and superior temporal cortices. In contrast, reduced self-prioritization was associated with damage to the right inferior temporal structures including the hippocampus and extending to the fusiform gyrus. In addition, lesions affecting fibers crossing the right temporal cortex, potentially disconnecting occipital-temporal from frontal regions, diminished the self-bias effect. The data highlight that self-prioritized face processing is linked to regions in the right hemisphere associated with face recognition memory and it also calls on executive processes in the left hemisphere that normally modulate self-prioritized attention.

Delusional misidentification syndromes in obsessive-compulsive disorder

Delusional misidentification syndromes (DMS) have been rarely reported in patients with conditions other than schizophrenia-related disorders, diffuse brain disease (dementia) and focal neurological illness. In this report, we describe DMS (i.e. Capgras and Fregoli syndromes) in two patients with severe and treatment resistant obsessive-compulsive disorder (OCD), one with paranoid personality disorder (PPD) and the other with a pervasive developmental disorder (PDD) not otherwise specified. While our findings highlight an interesting phenomenon (the occurrence of DMS in OCD), it is presently unclear whether this association is rare or underreported. Misidentification syndromes might be the ultimate result of a combination of obsessive fears and preexisting cognitive bias/deficits, such as mistrustfulness (in PPD) or poor theory of mind (in PDD).

Capgras syndrome in Dementia with Lewy Bodies

BACKGROUND

Capgras syndrome is characterized by the recurrent, transient belief that a person has been replaced by an identical imposter. We reviewed clinical characteristics of Dementia with Lewy Bodies (DLB) patients with Capgras syndrome compared to those without Capgras.

METHODS

We identified 55 consecutive DLB patients (11 cases with Capgras syndrome (DLB-C) and 44 cases without evidence of Capgras (DLB). Semi-structured interviews with the patient and an informant, neurological exams, and neuropsychological testing were performed. Caregivers were assessed for caregiver burden and depression. Primary comparisons were made between DLB-C and DLB. Exploratory analyses using stepwise logistic regression and bootstrap analyses were performed to determine clinical features associated with Capgras.

RESULTS

DLB-C patients experienced more visual hallucinations and self-reported anxiety, had higher scores on the Neuropsychiatric Inventory, and were less likely to be treated with cholinesterase inhibitors at time of initial evaluation. Extrapyramidal symptoms and depression were not associated with Capgras. Caregivers of DLB-C patients had higher caregiver burden. DLB-C was associated with self-reported anxiety (OR = 10.9; 95% CI = 2.6-47.6). In a bootstrap analysis, clinical findings that were predictors of Capgras included visual hallucinations (log(OR) = 18.3; 95% CI = 17.9-19.3) and anxiety (log(OR) = 2.9; 95% CI = 0.31-20.2).

CONCLUSIONS

Our study suggests that Capgras syndrome is common in DLB and usually occurs in the presence of anxiety and visual hallucinations, suggesting related etiopathogenesis. Early appreciation of Capgras syndrome may afford the opportunity to alleviate caregiver burden and improve patient and caregiver outcomes.

Clinical features and imaging findings in a case of Capgras syndrome

Capgras syndrome consists of the delusional belief that a person or persons have been replaced by doubles or impostors. It can occur in the context of both psychiatric and organic illness, and seems to be related to lesions of the bifrontal and right limbic and temporal regions. Indeed, magnetic resonance imaging has revealed brain lesions in patients suffering from Capgras syndrome. This case study reports the findings of a thorough diagnostic evaluation in a woman suffering from Capgras syndrome and presenting with the following clinical peculiarities: obsessive modality of presentation of the delusional ideation, intrusiveness of such ideation (that even disturbed her sleep), as well as a sense of alienation and utter disgust towards the double. These characteristics bring to mind the typical aspects of obsessive-compulsive disorder. Neuroanatomic investigation, through magnetic resonance imaging, performed on this patient showed alteration of the bilateral semioval centers, which are brain regions associated with the emotion of disgust and often show alterations in subjects suffering from obsessive-compulsive disorder. Hence, neuroimaging allows researchers to put forward the hypothesis of a common neuroanatomic basis for Capgras syndrome and obsessive-compulsive disorder, at least for cases in which the delusional ideation is associated with deep feelings of disgust and presents with a certain pervasiveness.

Capgras-like syndrome in a patient with an acute urinary tract infection

Delusional misidentification syndromes are a group of delusional phenomena in which patients misidentify familiar persons, objects, or themselves, believing that they have been replaced or transformed. In 25%-40% of cases, misidentification syndromes have been reported in association with organic illness. We report an acute episode of Capgras-like delusion lasting 8 days, focused on the idea that people were robots with human bodies, in association with an acute urinary infection. To our knowledge, this is the first case report associating urinary tract infection with Capgras-like syndrome. Awareness of the prevalence of delusional misidentification syndromes associated with acute medical illness should promote diligence on the part of clinicians in recognizing this disorder.

An effective environmental intervention for management of the 'mirror sign' in a case of probable Lewy body dementia

The term 'mirror sign' refers to the inability to recognize the reflection of oneself in a mirror, while the ability to recognize others' faces often remains intact. In this article, we present a case of an 85-year-old woman, with probable Lewy body dementia, who stably exhibited a delusional 'mirror sign' for a period of 9 months. Following a straightforward, ecological, non-pharmacological intervention, her 'mirror sign' delusion was no longer present.

Clinical picture and treatment implication in a child with Capgras syndrome: a case report

Introduction

Capgras syndrome is a delusional misidentification syndrome characterized by the patient’s belief that his or her relatives have been replaced by impostors.

Case presentation

Here we describe the clinical picture and the therapeutic approach to an 11-year-old Caucasian girl with Capgras syndrome. A complete psychopathological assessment was conducted during the acute phase, at one month, two months and six months since diagnosis.

Conclusion

Subsequent follow-up evaluations in this patient allowed us to detect improvements in the psychotic symptoms following treatment with risperidone and selective serotonin reuptake inhibitors, suggesting that this combined therapy may significantly improve the clinical outcome in patients who have Capgras syndrome.

The very same thing: Extending the object token concept to incorporate causal constraints on individual identity

The contributions of feature recognition, object categorization, and recollection of episodic memories to the re-identification of a perceived object as the very same thing encountered in a previous perceptual episode are well understood in terms of both cognitive-behavioral phenomenology and neurofunctional implementation. Human beings do not, however, rely solely on features and context to re-identify individuals; in the presence of featural change and similarly-featured distractors, people routinely employ causal constraints to establish object identities. Based on available cognitive and neurofunctional data, the standard object-token based model of individual re-identification is extended to incorporate the construction of unobserved and hence fictive causal histories (FCHs) of observed objects by the pre-motor action planning system. It is suggested that functional deficits in the construction of FCHs are associated with clinical outcomes in both autism spectrum disorders and later-stage stage Alzheimer’s disease.

A romantic delusion: de Clerambault's syndrome in dementia

Erotromania (also known as de Clerambault's syndrome) is a rare disorder in which an individual has a delusional belief that a person of a socially higher standing falls in love with her/him. It has rarely been described in older people, but many cases have been reported in conjunction with psychiatric and neurological disorders. The purpose of this paper was to examine the phenomenon of erotomania in people with dementia. We carried out a search of electronic databases for literature on this subject. The search terms used were: erotomania, de Clerambault's syndrome, erotomanic delusion and dementia. The literature on erotomania in the course of dementia consists mostly of case reports and small samples of patients. Misinterpretation of events is common in brain disease, especially with diffuse or multifocal disorders, but erotomania has rarely been reported in dementia. The relationship between dementia and de Clerambault's syndrome remains uncertain. Erotic delusion arising late in life should be thoroughly investigated to rule out organicity.

Dream experience and a revisionist account of delusions of misidentification

Standard accounts of delusion explain them as responses to experience. Cognitive models of feature binding in the face recognition systems explain how experiences of mismatch between feelings of "familiarity" and faces can arise. Similar mismatches arise in phenomena such as déjà and jamais vu in which places and scenes are mismatched to feelings of familiarity. These cognitive models also explain similarities between the phenomenology of these delusions and some dream states which involve mismatch between faces, feelings of familiarity and identities. Given these similarities it makes sense to retain that aspect of the standard account in the face of revisionist arguments that feature binding anomalies which lead to delusions of misidentification are not consciously experienced.

Neuropsychological research in delusional disorder: a comprehensive review

In recent decades, there has been a growing interest in the field of delusions, and different aspects of delusional disorder (DD) have been investigated. However, DD is still one of the most underresearched psychiatric disorders. In this paper, we review the literature on DD and most of the theoretical approaches proposed to explain the development and maintenance of delusions. DD research is infrequent, and delusions in this disorder have been scarcely investigated. We aim to establish the state of the art of delusions research to date and point to the shortage of neuropsychological studies in patients with DD. We also justify the need for future research into the neuropsychological correlates of DD as measured in patients with this disorder given that most previous research has mainly focused on other psychotic conditions.

[Capgras syndrome: a proposal of neuropsychological battery for assessment]

Capgras syndrome is the most prevalent of the delusional misidentification syndromes. It appears in both psychiatric illness and organic brain damage. Cognitive and neuropsychiatric models (lateralization and disconnection) have been proposed to explain the syndrome. From a neuropsychological point of view Capgras syndrome seems to be due to damage of bifrontal and right limbic and temporal regions. Memory, feeling of familiarity, monitoring of self and reality would be altered. All of these cause a failure to adequately integrate the information about emotions and facial recognition. Relative preservation of the left frontal lobe may be necessary for the development of delusional response. There does not seem to be a differential pattern as regards the aetiology, but there is a common underlying neuropsychiatric mechanism. Based on theoretic models, and clinics features, we propose a neuropsychological battery to assess the Capgras syndrome, that should be sensitive to the main expected deficits.

Visuospatial perspective taking in a dynamic environment: perceiving moving objects from a first-person-perspective induces a disposition to act

Spatial perspective taking is an everyday cognitive process that is involved in predicting the outcome of goal directed behavior. We used dynamic virtual stimuli and fMRI to investigate at the neural level whether motion perception interacts with spatial perspective taking in a life-like design. Subjects were asked to perform right-left-decisions about the position of either a motionless, hovering (STATic) or a flying ball (DYNamic), either from their own (1PP) or from the perspective of a virtual character (avatar, 3PP). Our results showed a significant interaction of STIMULUS TYPE and PERSPECTIVE with significantly increased activation in right posterior intraparietal sulcus (IPS) for 1PPDYN condition. As the IPS is critically involved in the computation of object-directed action preparation, we suppose that the simple perception of potentially action-relevant dynamic objects induces a 'readiness for (re)action', restricted to the 1PP. Results are discussed against the background of current theories on embodiment and enactive perception.

Somatoparaphrenia: a body delusion. A review of the neuropsychological literature

A review of published brain-damaged patients showing delusional beliefs concerning the contralesional side of the body (somatoparaphrenia) is presented. Somatoparaphrenia has been reported, with a few exceptions, in right-brain-damaged patients, with motor and somatosensory deficits, and the syndrome of unilateral spatial neglect. Somatoparaphrenia, most often characterized by a delusion of disownership of left-sided body parts, may however occur without associated anosognosia for motor deficits, and personal neglect. Also somatosensory deficits may not be a core pathological mechanism of somatoparaphrenia, and visual field disorders may be absent. Deficits of proprioception, however, may play a relevant role. Somatoparaphrenia is often brought about by extensive right-sided lesions, but patients with posterior (parietal-temporal), and insular damage are on record, as well as a few patients with subcortical lesions. Possible pathological factors include a deranged representation of the body concerned with ownership, mainly right-hemisphere-based, and deficits of multisensory integration. Finally, the rubber hand illusion, that brings about a bodily misattribution in neurologically unimpaired participants, as somatoparaphrenia does in brain-damaged patients, is briefly discussed.

The diagnosis and treatment of individuals with mental illness and developmental disabilities: an overview

BACKGROUND

The assessment and treatment psychiatric disorders among individuals with developmental disorders is in a state of flux. Clinicians working in this field confront two heterogeneous conditions based on separate but overlapping biopsychosocial bodies of scientific and clinical experiences.

METHODS

The paper is a review of the relevant literature and an effort to synthesize sokme of the major problem areas in differential diagnosis and treatment planning.

RESULTS

There are many genetic, metabolic and neurobehavioral factors that influence both challenging behaviors and the emergence, recognition, and clinical course of mental disorders in people with developmental disorders. As such, clinicians need to redefine dichotomous thinking about boundaries between psychiatrics, neurologic, and behavioral disorders and therapies.

DISCUSSION

Even though there are efforts to adapt our various systems of nomenclature for individuals with developmental disorders, most still rely on descriptive and categorical models. It may be time to reconsider models that incorporate etiological factors in the process of differential diagnosis and classification. By doing so, clinicians may enhance their capacity to match individuals with more finely tuned treatment plans.

A prospective study of delusional misidentification syndromes in Parkinson's disease with dementia

Delusional misidentification syndromes (DMS) are a group of neuropsychiatric disorders due to disturbances in familiarity. DMS in organic diseases have been related to deficits in executive, memory, and visuospatial function. DMS are frequently reported in dementia with Lewy bodies (DLB). The presence of DMS in Parkinson's disease with dementia (PDD), which shares similar clinical and neuropsychological features with DLB, has not been studied. We describe the frequency and clinical features of DMS in a cohort of PDD patients, and we compare the neuropsychological profile between PDD patients with and without DMS. Prospective study of 30 PDD patients recruited from an outpatient setting, who received a structured behavioral interview assessing DMS and hallucinations, and a neuropsychological battery assessing executive function, memory, language, and visuospatial abilities. DMS were found in 16.7% of PDD patients. All DMS subjects also exhibited hallucinations that were significantly more severe than in PDD without DMS. DMS were responsive to neuroleptic drugs. PDD subjects with DMS presented a different neuropsychological profile than PDD subjects without DMS, with more severe memory and language deficits, but similar levels of executive and visuospatial impairment. DMS is a neuropsychiatric feature associated with PDD. Greater impairment in language and memory in PDD with DMS suggests a prominent role of the temporal cortex in the genesis of DMS in PDD.

CASE REPORTS: Psychiatric Illness Presenting with a Sexual Complaint and Management by Psychotropic Medications: A Case Report

INTRODUCTION

Sexual medicine healthcare professionals, who do not normally examine men and women with psychiatric disorders, need to be aware that those with psychiatric disorders can and do present with sexual medicine problems. In particular, psychiatric individuals may present with a variety of delusions including those that have sexual content or sexual implications. The rare disorder of reverse delusional misidentification syndrome may be encountered in schizophrenic patients and may be best managed by the combined team effort of a sexual medicine specialist and psychiatrist.

AIM

To report a case study that reiterates the assessment and sexual medicine management of a female with sexual dysfunction who believed she was transforming into a male.

METHODS

Case report of a woman who attended an outpatient clinic in an academic medical center.

RESULTS

A 60-year-old woman with a history of paranoid schizophrenia presented to a gynecologist for ovarian cancer screening. Evaluation revealed complaints that the patient's ovaries were testes that produced sperm and her clitoris was a penis capable of erection and ejaculation. Gynecological examination revealed only atrophic vaginitis. The patient was treated with local minimally absorbed vaginal estrogens and referred for psychological assessment and counseling. Psychotropic medication compliance was encouraged, weekly psychotherapy was continued, and delusional symptoms were minimized.

CONCLUSION

Sexual medicine healthcare providers should be prepared to manage sex health concerns of men and women with psychiatric disorders, including delusional misidentification syndrome, in conjunction with a psychiatrist.

Reduplicative paramnesia in Morvan's syndrome

BACKGROUND

Morvan's syndrome is characterized by peripheral nervous system hyperexcitibility (myokymia and neuromyotonia), hyperhydrosis, sleep disorder, limb paresthesias, and encephalopathy. Voltage gated potassium channel antibodies (VGKC abs) are frequently present. Reduplicative paramnesia (RP) has not been reported with this disorder.

OBJECTIVE

To describe a patient with Morvan's syndrome presenting with RP.

DESIGN

Single case study.

PATIENT

A 64-year-old man with several years of myokymia and myoclonus with escalating parasomnia and confusion developed the delusion that a replica of his house and its contents existed 40 mi away.

RESULTS

Serum VGKC ab titer was elevated. Neuropsychological testing disclosed executive function and memory deficits. Electromyography demonstrated diffuse myokymia. Treatment with intravenous immunoglobulin and prednisone produced improvement of RP and myoclonus, but not myokymia.

CONCLUSION

RP may occur in patients with VGKC ab-associated Morvan's syndrome. Both RP and nervous system hyperexcitability may respond to immunotherapy including intravenous immunoglobulin and corticosteroids.