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PubMed2006

Delusion in general and forensic psychiatry--historical and contemporary aspects.

Delusion has always been a central topic for psychiatric research with regard to etiology and pathogenesis and to diagnosis, treatment, and forensic relevance. Throughout the history of psychiatry as a scientific discipline, there has been dissent on the issue of whether chronic delusion is a nosological entity of its own or just a specific type of another mental disorder, e.g. schizophrenia, mania, or personality disorder, and there already is a considerable literature on this. This article seeks to elucidate the central lines of thought that have governed the scientific debate on delusions and delusion-associated phenomena since the early 19th century. Special attention is given to the practical relevance of these theoretical considerations for forensic questions and psychiatric research. Due to the complex features of delusions, research in this area may well become paradigmatic for many other complicated psycho(patho)logical phenomena, e.g. consciousness, hallucinations and psychotic depression.

Anthropology↗

PubMed1999

[How is delusion possible in psychopathologic terms?].

Delusion is understood to mean inter-subjectively disconcerting convictions with a tendency toward subjective certainty that lose their disconcerting character when made the object of psychiatric analysis in the knowledge of their independence from mental disorder. The perceptions from which delusions arise are dynamically charged according to their role in the structural context. The realization pressure that burdens the perceptions and is intensified in psychotic constitutions is a precondition for the delusion. The failure of derealization brought about by the psychotic disorganisation of the structure is also a requirement. Based on a case study, considerations arising out of the initial stages of schizophrenic delusion are extended to other forms of delusion and to the conditions for chronification.

Adult↗

PubMed2005

Delusions and decision-making style: use of the Need for Closure Scale.

Clinicians and researchers have suggested that rapidity in belief formation, due to having a high 'need for closure' (NFC), may contribute to the acceptance of delusional explanations. The aim of the study is to determine whether NFC has such a direct link with delusions. A secondary aim is to examine if NFC is related to the delusion-associated reasoning process of 'jumping to conclusions'. One hundred and eighty-seven patients with psychosis, recruited for a treatment trial of psychological therapy (the PRP trial), completed the Need for Closure Scale (NFCS), symptom measures, and probabilistic reasoning tasks. The NFCS was considered in terms of its two dimensions: a desire for simple structure and a preference for quick, decisive answers. The individuals with psychosis reported being poor at making quick, decisive answers but required a greater need for simple structure. NFC was associated with levels of anxiety and depression. There were weak links between NFC and both positive and negative symptoms of psychosis, but these were explained by differences in affect. NFCS scores were unrelated to jumping to conclusions. Contrary to the argument that NFC is directly linked to delusions, individuals with delusions actually perceive themselves as indecisive. There was no evidence that NFC-at least as assessed by the NFCS-could be a proximal cause of delusions. Any potential effect on psychotic symptom presentation is indirect, mediated through affect. The use of the NFCS on its own in the study of psychotic symptoms cannot be recommended.

Adult↗

PubMed2006

Attributional style in a case of Cotard delusion.

Young and colleagues (e.g. Young, A. W., & Leafhead, K. M. (1996). Betwixt life and death: case studies of the Cotard delusion. In P. W. Halligan & J. C. Marshall (Eds.), Method in madness: Case studies in cognitive neuropsychiatry. Mahway, NJ: Lawrence Erlbaum Associates.) have suggested that cases of the Cotard delusion (the belief that one is dead) result when a particular perceptual anomaly (caused by a disruption to the affective component of visual recognition) occurs in the context of an internalising attributional style. This hypothesis has not previously been tested directly. We report here an investigation of attributional style in a 24-year-old woman with Cotard delusion ("LU"). LU's attributional style (and that of ten healthy control participants) was assessed using the Internal, Personal and Situational Attributions Questionnaire (Kinderman, P., & Bentall, R. P. (1996). A new measure of causal locus: the internal, personal and situational attributions questionnaire. Personality and Individual Differences, 20(2), 261-264.). LU showed a significantly greater proportion of internalising attributions than the control group, both overall and for negative events specifically. The results obtained thus support an association of Cotard delusion with an internalising attributional style, and are therefore consistent with the account of Young and colleagues. The potential brain basis of Cotard delusion is discussed.

Adult↗

PubMed2006

The effects of angry and happy expressions on recognition memory for unfamiliar faces in delusion-prone individuals.

Numerous studies suggest a cognitive bias for threat-related material in delusional ideation. However, few studies have examined this bias using a memory task. We investigated the influence of delusion-proneness on identity and expression memory for angry and happy faces. Participants high and low in delusion-proneness were presented with happy and angry faces and were later asked to recognise the same faces displaying a neutral expression. They also had to remember what the initial expressions of the faces had been. Remember/know/guess judgments were asked for both identity and expression memory. Results showed that delusion-prone participants better recognised the identity of angry faces compared to non-delusional participants. Also, this difference between the two groups was mainly due to a greater number of remember responses in delusion-prone participants. These findings extend previous studies by showing that delusions are associated with a memory bias for threat-related stimuli.

Adolescent↗

PubMed2005

Paranoia, persecutory delusions and attributional biases.

An influential model of persecutory delusions put forward by Bentall and colleagues hypothesizes that persecutory-deluded patients avoid the activation of negative self-beliefs by making externalising, personalising attributions for negative events. The first study reported here used a new instrument for the measurement of persecutory ideation, the Paranoid, Persecutory and Delusion-Proneness Questionnaire, to investigate whether attributional biases are associated with subclinical persecutory ideation. The second study extended this investigation by re-examining associations between attributional biases and persecutory delusions. Both studies used the Internal, Personal and Situational Attributions Questionnaire to measure attributional style. No evidence was found for a connection between attributional biases and subclinical persecutory ideation. Furthermore, there was no support for an association between persecutory delusions and an externalising bias, and only marginal support for the hypothesized relationship between persecutory delusions and a personalising bias. These results suggest that the putative link between persecutory ideation and attributional biases only manifests (if at all) when persecutory ideation is of delusional intensity, and that it is confined to a personalising bias.

Adolescent↗

PubMed2006

Diagnosing delusions: a review of inter-rater reliability.

Although several studies have examined the reliability of diagnosing delusions there is no comprehensive review of the literature. Therefore, the reliability of diagnosing 'delusions in general' and the subcategory of 'bizarre delusions' was reviewed, including both structured interview and standardized instrument methods. The literature suggests that delusions in general can be diagnosed reliably with both structured interview and standardized instruments. However, bizarre delusions are not reliably diagnosed by either, suggesting that this concept may have little clinical validity. Nevertheless, many of the studies reviewed are poorly designed or subject to significant confounds. Criteria are suggested for adequate future studies.

Delusions↗

PubMed1999

Delusions in Alzheimer's disease: spet evidence of right hemispheric dysfunction.

Delusional thinking and related behaviours are common symptoms in Alzheimer's disease (AD). The aim of the study was to determine if any consistent cerebral image pattern can be identified using Tc99m-hexamethylpropyleneamine (HMPAO) SPET in AD patients with and without delusions. 18 AD patients with delusion and 15 AD patients without delusion underwent neuropsychological testing and regional cerebral blood flow imaging using Tc99m-HMPAO SPET. The reconstructed data was compared using regions of interest drawn over each cerebral lobe and a statistical parametric mapping (SPM) approach. The neuropsychological testing showed that there was no difference in the profiles of the deluded and non deluded AD patients. The imaging results showed a significant degree of image asymmetry. This took the form of a right hemisphere hypoperfusion mainly in the right frontal and limbic regions. The results do not indicate a specific focal site of hypoperfusion in the patients with delusion. They do, however, indicate that delusions in AD may be associated with areas of hypoperfusion in the right anterior hemisphere.

Aged↗

PubMed2005

Reduced volume of parietal and frontal association areas in patients with schizophrenia characterized by passivity delusions.

BACKGROUND: In patients with schizophrenia, passivity delusions are characterized by a difficulty in determining the agency of purposive actions. Neuropsychological and functional neuroimaging data suggest that passivity delusions are associated with dysfunction of the parietal lobe association cortex. METHOD: Cortical volume calculated from magnetic resonance imaging data in a group of 12 patients with schizophrenia characterized by motor passivity delusions was compared statistically with the cortical volume of 11 patients without passivity delusions. RESULTS: Reduced cortical volume was observed in parietal and frontal association cortices in the passivity group. CONCLUSIONS: These data provide direct evidence for the involvement of the parietal lobe in the pathophysiology of passivity delusions in schizophrenia.

Adult↗

PubMed2000

Perception of threat in schizophrenics with persecutory delusions: an investigation using visual scan paths.

BACKGROUND: Cognitive theories of persecutory delusions in schizophrenia include increased attention to threat and reduced re-appraisal of information during decision-making. METHODS: We employed visual scan path measurements, an 'on-line' marker of attention, in schizophrenic patients with persecutory delusions (N = 19), negative symptom- and medication-matched patients with non-persecutory delusions (N = 8), and normal controls (N = 18). Stimuli comprised black-and-white photographs of social scenes rated as depicting either neutral, ambiguous or overtly threatening activity. Foreground areas containing salient information with regard to the overall scene were rated independently as either threatening or non-threatening in both the overtly threatening and ambiguous scenes; all foreground areas were rated as non-threatening in the neutral scene. RESULTS: For the ambiguous scene only, schizophrenics with persecutory delusions directed gaze to less threatening areas, and, for all three scenes, demonstrated reduced re-appraisal of information compared with both control groups. All subjects showed similar viewing strategies for the overtly threatening and neutral scenes. CONCLUSIONS: These findings suggest abnormal information gathering and evaluation in schizophrenics, specifically related to the presence of persecutory delusions. In particular, the results point to biased processing of contextual information in an ambiguous setting in these patients, and perhaps perception of threat in inappropriate places.

Adult↗

PubMed2000

Imaging attentional and attributional bias: an fMRI approach to the paranoid delusion.

BACKGROUND: The pathophysiology of auditory hallucinations and delusions of control has been elucidated using functional imaging. Despite their clinical importance, there have been few similar attempts to investigate paranoid delusions. We have examined two components of social cognition (attentional and attributional biases) that contribute to the formation and maintenance of paranoid delusions, using functional magnetic resonance imaging (fMRI). METHOD: Normal subjects performed tasks requiring attentional and attributional judgements. We investigated the neural response particularly associated with attention to threatening material relevant to self and with the 'self-serving' attributional bias. RESULTS: The determination of relevance to self of verbal statements of differing emotional valence involved left ventrolateral prefrontal cortex (left inferior frontal gyrus, BA 47), right caudate and right cingulate gyrus (BA 24). Attention to threatening material relevant to self differentially activated a more dorsal region of the left inferior frontal gyrus (BA 44). Internal attributions of events, where the self was viewed as an active intentional agent, involved left precentral gyrus (BA 6) and left middle temporal gyrus (BA 39). Attribution of events in a non 'self-serving' manner required activation of the left precentral gyrus (BA 6). CONCLUSIONS: Anomalous activity or connectivity within these defined regions may account for the attentional or attributional biases subserving paranoid delusion formation. This provides a simple model for paranoid delusion formation that can be tested in patients.

Adult↗

PubMed2003

Delusions of pregnancy associated with increased prolactin concentrations produced by antipsychotic treatment.

Treatment of psychotic symptoms has traditionally involved conventional antipsychotics. While efficacious, their side-effects have been problematic and the approval by the Food and Drug Administration of the newer antipsychotics with improved side-effects profiles heralded important advances in treating psychoses. Prolactin elevation has been associated with all classical and some atypical antipsychotics. We present cases where elevation of prolactin concentrations secondary to antipsychotic treatment was associated with delusions of pregnancy. Risperidone was the antipsychotic employed and elevation of prolactin concentrations were noted each time. The delusions abated and prolactin concentrations decreased when the drug was discontinued. Rechallenge with risperidone resulted in re-elevation of prolactin levels along with recurrent delusions. Substituting risperidone with another antipsychotic (either olanzapine or quetiapine) also led to abatement of the delusions and lowering of prolactin. Although no direct psychotogenic effects of prolactin are known, it is contended that delusions of pregnancy reported during antipsychotic treatment might be associated with rising prolactin concentrations.

Adult↗

PubMed2004

Reconceiving delusion.

Delusions are critical components in a number of mental disorders, schizophrenia foremost. What are they? The standard view is that they are a type of belief--a pathological belief. Unfortunately, the standard view does not consistently correspond to clinical practice, where the term 'delusion' often applies to non-beliefs. We review the case for saying that non-beliefs can count as delusions. We argue that delusions are complexes of higher and lower order attitudes. They constitute a distinctive type of failure of self-knowledge and self-management. We describe the relevant type. One of the conceptual implications of our view is that beliefs need not be central to delusions.

Culture↗

PubMed2007

Hopping, skipping or jumping to conclusions? Clarifying the role of the JTC bias in delusions.

INTRODUCTION: There is substantial evidence that patients with delusions exhibit a reasoning bias--known as the "jumping to conclusions" (JTC) bias--which leads them to accept hypotheses as correct on the basis of less evidence than controls. We address three questions concerning the JTC bias that require clarification. Firstly, what is the best measure of the JTC bias? Second, is the JTC bias correlated specifically with delusions, or only with the symptomatology of schizophrenia? And third, is the bias enhanced by emotionally salient material? METHODS: To address these questions, we conducted a series of meta-analyses of studies that used the Beads task to compare the probabilistic reasoning styles of individuals with and without delusions. RESULTS: We found that only one of four measures of the JTC bias--"draws to decision"--reached significance. The JTC bias exhibited by delusional subjects-as measured by draws to decision--did not appear to be solely an epiphenomenal effect of schizophrenic symptomatology, and was not amplified by emotionally salient material. CONCLUSIONS: A tendency to gather less evidence in the Beads task is reliably associated with the presence of delusional symptomatology. In contrast, certainty on the task, and responses to contradictory evidence, do not discriminate well between those with and without delusions. The implications for the underlying basis of the JTC bias, and its role in the formation and maintenance of delusions, are discussed.

Bias↗

PubMed1980

Are there delusions specific for paranoid disorders vs. schizophrenia?

DSM-III proposes that only persecutory delusions and delusions of jealousy can occur in paranoid disorders, all other types of delusions in the absence of an affective syndrome being indicative of schizophrenia. The scant empirical evidence relevant to this issue suggests that the type of delusion on admission is not predictive of outcome in patients with paranoid psychosis. These findings raise questions about the validity of the distinction drawn in DSM-III between types of delusions.

Delusions↗

PubMed1997

Reduced autonomic responses to faces in Capgras delusion.

People experiencing the Capgras delusion claim that others, usually those quite close emotionally, have been replaced by near-identical impostors. Ellis & Young suggested in 1990 that the Capgras delusion results from damage to a neurological system involved in orienting responses to seen faces based on their personal significance. This hypothesis predicts that people suffering the Capgras delusion will be hyporesponsive to familiar faces. We tested this prediction in five people with Capgras delusion. Comparison data were obtained from five middle-aged members of the general public, and a psychiatric control group of five patients taking similar anti-psychotic medication. Capgras delusion patients did not reveal autonomic discrimination between familiar and unfamiliar faces, but orienting responses to auditory tones were normal in magnitude and rate of initial habituation, showing that the hyporesponsiveness is circumscribed.

Acoustic Stimulation↗

PubMed1992

Delusions and behavioral disturbances in cognitively impaired elderly persons.

OBJECTIVE: To compare cognitive function and the prevalence of selected behavioral problems in delusional and non-delusional dementia patients. DESIGN: Retrospective medical record review. SETTING: An outpatient geriatric assessment center. PARTICIPANTS: 114 consecutive patients with dementia. MAIN OUTCOME MEASURES: Delusions as recorded in a consultation report. RESULTS: Delusions were described in 25.5% of patients. A variety of behavioral disturbances were more common in delusional than non-delusional patients, including agitation, angry or hostile outbursts, urinary incontinence, wandering or pacing, and insomnia. While cognitive function as measured by the MMSE was similar in delusional and non-delusional patients (18.9 +/- 3.8 and 19.2 +/- 5.9, respectively), there was a statistically borderline tendency for delusions to occur more often in patients in the mid-range of cognitive impairment (17 less than or equal to MMSE less than or equal to 23) compared with patients with greater or lesser degrees of cognitive impairment (32% vs 17% respectively). CONCLUSION: Delusions in dementia are associated with a variety of behavioral problems. Further studies are needed to clarify the role of delusions in the development of disruptive behaviors in dementing illness.

Aged↗

PubMed1993

Delusions in Alzheimer's disease and multi-infarct dementia.

Neuropsychiatric symptoms such as delusions and misidentifications have been reported in dementia ranging from 10% to 73% in Alzheimer's disease (AD) patients and up to 40% in multi-infarct dementia (MID) patients. The aim of this study was to investigate in 61 AD and 31 MID patients both the frequency and the content of delusions during the course of illness and to evaluate the relationship between these and both functional and mental decline. The results indicated that delusion experiences had occurred in 45% of AD patients and in 38% of MID patients, occurring most frequently during the first year of illness. Patients who experienced psychiatric symptoms showed higher mini mental state examination scores and were less impaired in functional disability measures. With regard to the content, no significant differences were observed between AD and MID patients; 53% of psychotic symptoms were found to be paranoid delusions while 47% were misidentification delusions.

Aged↗