The emergence of delusional companions in Alzheimer's disease: An unusual misidentification syndrome

  title={The emergence of delusional companions in Alzheimer's disease: An unusual misidentification syndrome},
  author={Michael Fraser Shanks and Annalena Venneri},
  journal={Cognitive Neuropsychiatry},
  pages={317 - 328}
Introduction. Misidentifications in the course of organic diseases, including Alzheimer's disease (AD), have been associated with right sided brain dysfunction. The reasons for this association might be clarified by investigating the contribution of neurobiological, cognitive and emotional factors to distinctive types of misidentification. Methods. This study reports the cases of three patients with AD presenting a novel misidentification delusion in which objects with intrinsically comforting… 
Neuroanatomical correlates of neuropsychiatric symptoms in Alzheimer's disease.
The study of neurodegenerative disorders such as Alzheimer's disease using voxel-based morphometry and other imaging modalities may further the understanding of the neural structures that mediate the genesis of abnormal behaviours.
Accelerated atrophy in dopaminergic targets and medial temporo-parietal regions precedes the onset of delusions in patients with Alzheimer’s disease
A pattern of faster GM loss in brain areas typically affected by AD and in cortical and subcortical targets of dopaminergic pathways, paralleled by worsening of episodic memory and behavioural symptoms, may explain the emergence of delusions in patients with AD.
Thinking through delusions in Alzheimer's disease Thinking through delusions in Alzheimer's disease
Functional neuroimaging studies of patients either with a history of delusions or with contemporary abnormal beliefs have implicated anterior brain structures and metabolic studies have implicated a more widespread network of cerebral dysfunctions.
Delusional Misidentification Syndromes in Patients of Paranoid Schizophrenia: Case Series and Review
Five cases of Delusional Misidentification in the setting of paranoid schizophrenia, either as a single DMS or combination of various DMS, like Fregoli, Capgras, and Clonal pluralization are reported.
Neuropathologies of the Self: A General Theory
The neuropathologies of the self are a continuum of disorders of the self and identity that occur in the presence of identifiable brain pathology. They include perturbations of the bodily,
Confabulation : constructing motivated memories
Neurological confabulation is a prototypical form of false remembering and as such, it can provide insight into the nature of human memory. The main aims of the thesis was to empirically investigate
A Neurology of Awareness and Belief: So Near So Far?
Cognitive neuroscientists have used cognitive frameworks to interpret the various forms of breakdown in the “belief” system (e.g., misidentification, anosognosia, confabulation, asomatognosia,
Late Onset First Episode Psychosis Emerging as Delusional Misidentification of Familiar Sacred Places During a Holy Pilgrimage: A Case Report and Literature Review
This case report is the first to present a DMS, emerging as a late onset first episode psychosis during the sacred journey of Hajj, and highlights the importance of early recognition and treatment of mental health conditions that may appear de novo during the Hajj sacred journey.


Delusions in Alzheimer's Disease: Spet Evidence of Right Hemispheric Dysfunction
Neuroanatomical correlates of clinical misidentification and misperception in senile dementia of the Alzheimer type.
It is concluded that an accentuated degeneration of the right frontal lobe (and a relative preservation of the left frontal lobe) may be associated with delusional misidentification symptoms in DAT.
Nurturing syndrome: a form of pathological bereavement with delusions in Alzheimer’s disease
Alteration of rCBF in Alzheimer's disease patients with delusions of theft
The data suggest that attention impairment or lack of awareness of illness caused by right parietal dysfunction might play a role in producing the delusion of theft.
Mirrored-self Misidentification: Two Cases of Focal Onset Dementia
It is proposed that a combination of cognitive deficits underlie the mirror sign delusion, including perceptual, affective and reasoning impairments, and also discusses the contributions of cortical and subcortical lesions in these two patients and in delusions in general.
Reflections of the Self: Atypical Misidentification and Delusional Syndromes in Two Patients with Alzheimer's Disease
Two patients with moderately severe AD, when asked directly, could identify their own images in a mirror, but also consistently misidentified their own reflections as that of another person, indicating the importance of the interaction between biological and psychological factors in the expression of such symptoms.
HMPAO SPECT imaging of Alzheimer's disease patients with similar content-specific autobiographic delusion: comparison using statistical parametric mapping.
This result suggests that autobiographic delusions in AD may have an identifiable neuropsychologic mechanism and that it may be possible to identify an organic cause in some patients using 99mTc-HMPAO SPECT.
Cerebral correlates of psychotic symptoms in Alzheimer's disease
Patients with Alzheimer's disease who manifest psychosis may have disproportionate dysfunction of frontal lobes and related subcortical and parietal structures.
Psychiatric, neurological and medical aspects of misidentification syndromes: a review of 260 cases.
The patients with reduplicative paramnesia more frequently suffered from head trauma or cerebral infarction and showed more features of right hemisphere lesions on neuropsychological testing or CT scan than the patients with other misidentification syndromes.
The role of the right hemisphere in the Capgras delusion.
There was no difference in performance when the faces appeared bilaterally, which fails to support the hypothesis that poor interhemispheric communication may give rise to CD, and a model of what may be the right hemisphere mechanisms giving rise toCD was explored.