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Background: Some individuals may manifest psychotic symptoms that do not fulfill the requisite clinical criteria for a formal diagnosis of psychosis. The assessment of susceptibility to delusions, encompassing both clinical and non-clinical cohorts, frequently makes use of the Peters et al. Delusions Inventory (PDI-40). This study aimed to evaluate the reliability and validity of the Persian version of Peters et al. Delusions Inventory (PDI-40) in Iranian non-clinical and clinical samples., Methods: The present study employed a cross-sectional, correlational design in 2020. A total of 1402 Iranian participants were recruited for the study, which consisted of three distinct stages. The first stage involved an Exploratory Factor Analysis (EFA) conducted on a non-clinical sample of 512 participants. The second stage comprising different non-clinical sample 764 participants to perform a Confirmatory Factor Analysis (CFA). In the third stage, a clinical sample of 126 psychotic patients was compared to a non-clinical sample. All participants completed the PDI-40, the Community Assessment of Psychotic Experiences (CAPE-42), and the Depression, Anxiety, and Stress Scale (DASS-21). The internal structure of PDI-40 was examined through the analysis of its factor structure using LISREL 8.8., Results: The EFA analysis unveiled nine components within Persian version of PDI-40. The CFA analysis demonstrated an excellent fit of the nine-factor structure of Persian PDI-40 to the data. The total score exhibited high internal reliability, as indicated by Cronbach's alpha coefficient of 0.92. Moreover, Persian PDI-40 exhibited satisfactory evidence of convergent validity, as significant correlations were observed between dimensions of PDI-40 and subscales of CAPE-42 and DASS-21. Lastly, findings indicated that psychotic participants scored higher than non-clinical participants in all components of the PDI-40(p < 0.05)., Conclusion: Persian version of the PDI-40 demonstrates strong reliability and validity for assessing delusion proneness in both non-clinical and clinical samples in Iran. The observed distinctions between psychotic and non-clinical participants underscore its potential as a valuable tool for discerning delusion proneness in diverse contexts., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Studies on cognitive behavioural therapy for psychosis (CBTp) have developed from evaluating generic approaches to focusing on specific symptoms. The evidence for targeted studies on delusions and hallucinations was reviewed. We included randomized controlled trials (RCTs) examining the effect of individualized CBT-based interventions focusing either on delusions or on hallucinations. Twelve suitable RCTs were identified. Four RCTs focused on delusions, of which three took a focused approach targeting mechanisms assumed causal to persecutory delusions. Eight RCTs focused on hallucinations, a common component of these studies being a focus on the perceived power imbalance between the voice(s) and the voice-hearer, to reduce distress and dysfunction. Only three RCTS were powered adequately; the remainder were pilot trials. All trials reported effect sizes against treatment-as-usual above d=0.4 on at least one primary outcome at post-therapy, with several effects in the large range. Effects on the primary outcome were maintained for five of the seven studies that had significant outcomes and reported a follow-up comparison, but most of the follow-up periods were brief. Although targeted studies are still in their infancy, the results are promising with a tendency towards higher effects compared to the small-to-moderate range found for generic CBTp. In clinical practice, CBTp will need to continue including a range of approaches that can be adapted to patients in a flexible manner according to the primary goals and prevalent combination of symptoms. However, symptom-focused and causal-interventionist approaches are informative research strategies to evaluate the efficacy of separate components or mechanisms of generic CBTp., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Introduction: There is an ongoing debate about whether negative affect are consequences or triggers of paranoid thinking. It has also been suggested that aberrant salience is central to the development of delusions. This study modelled the moment-to-moment relationships between negative affect, aberrant salience, and paranoia in acute inpatients with psychosis., Methods: Participants with active paranoid delusions were assessed using clinical rating scales and experience sampling method (ESM) over 14 days. ESM data were analysed using time-lagged multilevel regression modelling., Results: Both negative affect and aberrant salience predicted an increase in paranoia at the next time point. Conversely, the level of paranoia did not predict subsequent changes in negative affect or aberrant salience. Negative affect predicted an increase in aberrant salience at the next time point, and vice versa., Conclusions: Negative affect and aberrant salience appear to drive and exacerbate paranoia, rather than being merely the sequelae of the symptom. Our results suggest both direct and indirect (via aberrant salience) pathways from negative affect to paranoia.

Background: Persecutory delusions are the most common type of delusions in psychosis and present in around 10-15% of the general population. Persecutory delusions are thought to be sustained by biased cognitive and emotional processes. Recent advances favour targeted interventions, focussing on specific symptoms or mechanisms. Our aim is to test the clinical feasibility of a novel psychological intervention, which manipulates biased interpretations toward more adaptive processing, in order to reduce paranoia in patients., Methods: The 'Cognitive Bias Modification for paranoia' (CBM-pa) study is a feasibility, double-blind, randomised controlled trial (RCT) for 60 stabilised outpatients with persistent, distressing paranoid symptoms. Patients will be randomised at a 50:50 ratio, to computerised CBM-pa or a text-reading control intervention, receiving one 40-min session per week, for 6 weeks. CBM-pa involves participants reading stories on a computer screen, completing missing words and answering questions about each story in a way that encourages more helpful beliefs about themselves and others. Treatment as Usual will continue for patients in both groups. Patients will be assessed by a researcher blind to allocation, at baseline, each interim session, post treatment and 1- and 3-month follow-up post treatment. The primary outcome is the feasibility parameters (trial design, recruitment rate and acceptability) of the intervention. The secondary outcomes are clinical symptoms (including severity of paranoia) as assessed by a clinical psychologist, and 'on-line' measurement of interpretation bias and stress/distress. The trial is funded by the NHS National Institute for Health Research., Discussion: This pilot study will test whether CBM-pa has the potential to be a cost-effective, accessible and flexible treatment. If the trial proves feasible and demonstrates preliminary evidence of efficacy, a fully powered RCT will be warranted., Trial Registration: Current Controlled Trials ISRCTN: 90749868 . Retrospectively registered on 12 May 2016.

Recent decades have seen a surge of research interest in the phenomenon of healthy individuals who experience auditory verbal hallucinations, yet do not exhibit distress or need for care. The aims of the present systematic review are to provide a comprehensive overview of this research and examine how healthy voice-hearers may best be conceptualised in relation to the diagnostic versus 'quasi-' and 'fully-dimensional' continuum models of psychosis. A systematic literature search was conducted, resulting in a total of 398 article titles and abstracts that were scrutinised for appropriateness to the present objective. Seventy articles were identified for full-text analysis, of which 36 met criteria for inclusion. Subjective perceptual experience of voices, such as loudness or location (i.e., inside/outside head), is similar in clinical and non-clinical groups, although clinical voice-hearers have more frequent voices, more negative voice content, and an older age of onset. Groups differ significantly in beliefs about voices, control over voices, voice-related distress, and affective difficulties. Cognitive biases, reduced global functioning, and psychiatric symptoms such as delusions, appear more prevalent in healthy voice-hearers than in healthy controls, yet less than in clinical samples. Transition to mental health difficulties is increased in HVHs, yet only occurs in a minority and is predicted by previous mood problems and voice distress. Whilst healthy voice-hearers show similar brain activity during hallucinatory experiences to clinical voice-hearers, other neuroimaging measures, such as mismatch negativity, have been inconclusive. Risk factors such as familial and childhood trauma appear similar between clinical and non-clinical voice-hearers. Overall the results of the present systematic review support a continuum view rather than a diagnostic model, but cannot distinguish between 'quasi' and 'fully' dimensional models. Healthy voice-hearers may be a key resource in informing transdiagnostic approaches to research of auditory hallucinations., (Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Delusional experiences can be considered on a range of dimensions including conviction, distress, preoccupation, and disruption, which have been shown to be related to depression and anxiety. This study aimed to test the hypotheses that delusional conviction is less responsive to antipsychotic treatment than delusional distress and preoccupation, and that depression and anxiety reduce alongside improvements in delusional dimensions. Forty acutely ill inpatients with delusions were assessed during their early stage of antipsychotic treatment. Interview data were analysed using mixed models for repeated measures. There was a significant reduction in psychotic symptoms over eight weeks, after controlling for baseline dosage of antipsychotics. We found no differential rate of improvement across delusional dimensions, and all dimensions improved over time. However, conviction ratings remained relatively high throughout the eight weeks. There was no significant improvement in anxiety and depression, and delusional preoccupation covaried with anxiety and depression throughout eight weeks, suggesting a relationship between emotional and delusional processes during the early recovery phase of psychosis., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

The Psychotic Symptom Rating Scales (PSYRATS) is an instrument designed to quantify the severity of delusions and hallucinations and is typically used in research studies and clinical settings focusing on people with psychosis and schizophrenia. It is comprised of the auditory hallucinations (AHS) and delusions subscales (DS), but these subscales do not necessarily reflect the psychological constructs causing intercorrelation between clusters of scale items. Identification of these constructs is important in some clinical and research contexts because item clustering may be caused by underlying etiological processes of interest. Previous attempts to identify these constructs have produced conflicting results. In this study, we compiled PSYRATS data from 12 sites in 7 countries, comprising 711 participants for AHS and 520 for DS. We compared previously proposed and novel models of underlying constructs using structural equation modeling. For the AHS, a novel 4-dimensional model provided the best fit, with latent variables labeled Distress (negative content, distress, and control), Frequency (frequency, duration, and disruption), Attribution (location and origin of voices), and Loudness (loudness item only). For the DS, a 2-dimensional solution was confirmed, with latent variables labeled Distress (amount/intensity) and Frequency (preoccupation, conviction, and disruption). The within-AHS and within-DS dimension intercorrelations were higher than those between subscales, with the exception of the AHS and DS Distress dimensions, which produced a correlation that approached the range of the within-scale correlations. Recommendations are provided for integrating these underlying constructs into research and clinical applications of the PSYRATS., (© The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.)

Background: There is evidence that people with psychosis display a "jump-to-conclusions" (JTC) reasoning style, and that this bias may be specific to delusions. A "jump-to-perceptions" (JTP) cognitive bias has also been found and is typically linked to hallucinations. However, there is some evidence for an association between JTP and delusions, and its specificity to hallucinations remains unclear. It has been suggested that these biases are related and products of shared cognitive processes., Methods: This study examined the symptom specificity of JTC and JTP, and the relationship between them, in a sample of 98 individuals with delusions divided into 'hallucinators' (n=51) and 'non-hallucinators' (n=47). Biases were assessed using the beads task and visual and auditory perceptual tasks., Results: As predicted, both groups demonstrated a JTC bias, but the 'hallucinators' showed a more pronounced JTP style in both modalities. The presence of JTC and JTP biases did not co-occur: making a decision on the beads task after two or fewer draws was not related to visual JTP, and was associated with a less marked JTP bias in the auditory perceptual task. No differences were found in JTP or JTC between participants with and without a schizophrenia diagnosis. JTP, but not JTC, was associated with the presence of hallucinations., Conclusions: These findings suggest that the JTC and JTP biases show specificity to delusions and hallucinations, respectively, and not to diagnosis. There was no evidence that they are the product of shared cognitive processes, further supporting their specificity., (Copyright © 2014 Elsevier B.V. All rights reserved.)

It has been suggested that different aspects of delusions (conviction, distress, preoccupation) respond to treatment at different rates, and that the cognitive bias of 'Jumping to Conclusions' (JTC) may predict treatment outcome. This study investigates changes in delusion dimensions using Experience Sampling Methodology (ESM) and the role of JTC as a predictor of change during the initial 2 weeks of antipsychotic treatment on admission to hospital. Sixteen acute patients with delusions were assessed seven times per day for 14 days using computerised ESM. ESM assessed moment-by-moment experiences of affect, psychotic symptoms, and delusion dimensions. Clinical ratings were completed at baseline, 1 week and 2 weeks later. The 'beads' task was used to measure JTC at baseline. Delusion dimensions improved over the two weeks of antipsychotic treatment and admission to hospital. Different delusional dimensions changed at different rates, with distress and disruption being more responsive than conviction and preoccupation on both PSYRATS and ESM ratings. Eight out of 16 participants showed a JTC bias on the beads task at baseline. Exploratory analyses showed that JTC predicted changes in the ESM ratings of delusion conviction and distress, suggesting that reasoning biases may predict treatment response., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Objectives: Understanding factors that contribute to delusional ideation has important clinical implications. This study looked at the impact of mindfulness and negative schemas on changes in delusional ideation over time., Design: A sample of University students was selected to investigate processes related to delusional ideation in a non-clinical sample., Method: A web-based survey was completed by 700 University students, 204 of whom completed a second identical survey after 6 months, to comprise the longitudinal sample., Results: Results from the study demonstrated that negative schemas and mindfulness were related to changes in delusional ideation over time and support was found for a mediated model, whereby mindfulness mediated the impact of schemas on the outcome., Conclusions: The findings point to the importance of mindfulness as an intervention for preventing non-clinical delusional ideation transitioning into clinical delusions., (© 2011 The British Psychological Society.)

Objective: To explore how reasoning biases in schizophrenic patients respond to treatment. Patients with schizophrenia, especially those with delusions, show not only cognitive deficits but also "reasoning biases," namely, "jumping to conclusions," reduced belief flexibility, an externalizing attributional style, and an impaired "theory of mind.", Methods: This is a systematic review of 17 longitudinal and cross-sectional studies., Results: "Jumping to conclusions" and reduced "belief flexibility" are most closely related to the severity of delusions, whereas "theory of mind" is better related to negative symptoms and "attributional style" to overall psychopathology. Antipsychotic treatment leads to an improvement in belief flexibility and theory of mind, with the suggestion that "belief flexibility" may be mediating the treatment response. On the other hand, the "jumping to conclusions" bias is likely a stable "trait" factor, which does not change with treatment, although it may moderate the outcome of response. The findings above are offered with the caveat that most of the available studies are small, often uncontrolled, few are longitudinal, that the measurement of some of the reasoning measures varies across studies, and that their relationship to the more established "cognitive" deficits remains unclear., Conclusions: The fact that these reasoning biases could be moderators and mediators of treatment outcome provides a greater impetus to study them systematically.

Introduction: Previous research has suggested that biases in cognitive processes involved in everyday reasoning may contribute to the development of delusional beliefs. The aim of this study was to explore jumping to conclusions (JTC), a data-gathering bias, and jumping to perceptions (JTP), a bias towards believing ambiguous perceptual events are real and external., Methods: Individuals with current delusions (n=17), remitted delusions (n=17), both recruited from an early psychosis service, and nonclinical participants (n=35) were compared on a probabilistic reasoning task, an auditory perceptual bias task, and the Barely Visible Words task., Results: The deluded participants did not demonstrate the expected JTC bias; therefore the relationship between JTC and JTP could not be examined. However, both clinical groups exhibited a JTP bias on the auditory perceptual bias task. In contrast, the lowered perceptual threshold for threat displayed by the control group was absent in the clinical groups., Conclusions: These results suggest that the JTP bias may be a trait characteristic in those with a propensity to delusions, and that these individuals may also show a bias away from threat.

Objective: To investigate the specificity of the 'jump-to-conclusions' (JTC) bias in delusions., Methods: Thirty-seven psychotic patients were divided into two separate groupings: (1) deluded versus non-deluded individuals and (2) individuals with and without a diagnosis of schizophrenia. Groups were compared on three reasoning tasks ('Beads' task, Wason's 2-4-6 task, and Wason's selection task)., Results: Deluded participants had a tendency to show a JTC bias on data-gathering tasks, but no differences were found with the schizophrenia diagnosis grouping. There were no differences between any groups on tasks of general reasoning and probability judgments., Conclusion: The results suggest that JTC is specific to delusions rather than diagnosis, and to data gathering rather than a general deficit in reasoning.

This study investigated the role of need for closure (NFC) and anxiety in delusions. The Need For Closure Scale (NFCS) and measures of trait and state anxiety were administered to an early psychosis group with current delusions, a clinical (generalised anxiety disorder--GAD) control group and a non-clinical control group. The battery of questionnaires was repeated at follow-up one year later. The NFCS did not meet criteria for a unidimensional scale and two sub-scales were removed from all further analyses. At baseline the deluded and GAD groups scored significantly higher on the reduced NFCS (NFCS-R) than the control group. Trait anxiety was related to NFCS-R in the GAD and non-clinical control groups, but not in the deluded group. At follow-up all groups scored significantly lower on the NFCS-R, perhaps suggesting a practice effect, although the two clinical groups continued to have higher scores than the non-clinical control group. The recovered and non-recovered deluded groups did not differ on the NFCS-R one year later, unlike in the GAD group where recovered participants had significantly lower scores than the non-recovered. Change scores on the NFCS-R and trait anxiety were correlated at trend level in the GAD and non-clinical control groups, but not in the deluded group. These findings suggest that whilst NFC and trait anxiety are related in non-psychotic groups, NFC may be implicated in the formation of delusions, independently of anxiety, in psychotic individuals.

Background and Aims: It has been suggested that delusions may serve as a defence against negative self-representations. The present study investigated general psychological well-being and evidence for defensive emotional processes among people with late-onset psychosis., Method: The performance and responses of older people with late-onset psychosis (n = 13), older people with depression (n = 15), and age-matched healthy controls (n = 15) were compared in a cross-sectional design. Participants rated their own levels of depression and self-esteem, and completed an emotional Stroop task to establish whether there was evidence of implicit depression in the absence of explicit acknowledgement. Participants rated themselves on a number of personal attributes in relation to two life stages to generate discrepancies in 'actual', 'ideal' and 'other' self-concepts, and completed measures of their perceptions of current and past psychological well-being., Results: People with late-onset psychosis showed no evidence of overt depression or low-self esteem. All three groups showed an attentional bias to depression-related and age-related words, although response times overall were faster for controls. The psychosis group showed no discrepancies between either their past or their current 'actual' and 'other' self-concepts, suggesting that they do not have more negative views about how others see them., Conclusions: Evidence from this study does not support the application of the 'delusion-as-defence' model to late-onset psychosis, but methodological constraints must be borne in mind when interpreting the findings.

Background: This study explored the longitudinal course of the relationship between delusions and different aspects of cognitive functioning., Methods: Deluded patients were compared to psychiatric and non-clinical controls on three tasks: negative priming, a probabilistic judgement task (the 'beads' task), and the pragmatic inference task (PIT). All groups were tested at two time points, once when actively symptomatic, and once when in remission., Results: Deluded individuals exhibited a 'jump-to-conclusions' (JTC) reasoning bias: i.e., they made decisions on the basis of limited evidence and were more likely to revise their estimates when faced with disconfirmatory evidence. This JTC bias remained stable over time, although probability judgments seemed to normalise in remission. No deficits in cognitive inhibition were found on negative priming. The deluded group displayed an excessive self-focus on the PIT at both time points, but did not show a depressive attributional style. Only a small sub-sample, characterised by the "bad-me" type of paranoia [Trower & Chadwick, 1995 Clinical Psychology: Science and Practice, 2, 263-278.], demonstrated depressive schemas when symptomatic, but no longer did so when remitted. Few relationships were found between tasks, suggesting that different areas of functioning are relatively independent. The only measures associated with delusion symptom scores were from the 'beads' task., Conclusions: Overall these findings suggest that the JTC bias is a stable factor associated with delusional thinking, while the depressive attributional style characteristic of a small sub-sample of paranoid patients fluctuates with delusional course.

Reasoning biases have been identified in deluded patients, delusion-prone individuals, and believers in the paranormal. This study examined content-specific reasoning and delusional ideation in believers in the paranormal. A total of 174 members of the Society for Psychical Research completed a delusional ideation questionnaire and a deductive reasoning task. The reasoning statements were manipulated for congruency with paranormal beliefs. As predicted, individuals who reported a strong belief in the paranormal made more errors and displayed more delusional ideation than skeptical individuals. However, no differences were found with statements that were congruent with their belief system, confirming the domain-specificity of reasoning. This reasoning bias was limited to people who reported a belief in, rather than experience of, paranormal phenomena. These results suggest that reasoning abnormalities may have a causal role in the formation of unusual beliefs. The dissociation between experiences and beliefs implies that such abnormalities operate at the evaluative, rather than the perceptual, stage of processing.

There is increasing evidence that in the general population there are schizotypal traits and symptoms that can be measured psychometrically. Norms are reported for a new 21-item version of the Peters et al. Delusions Inventory (PDI; Peters et al. 1999b). The PDI, originally based on the Present State Examination, incorporates the multidimensionality of delusions by including measures of distress, preoccupation, and conviction. A total of 444 healthy individuals completed the 21-item PDI and two other questionnaires measuring florid delusions and social desirability. A subsample also filled out an in-depth schizotypal personality scale. Thirty-three deluded inpatients also completed the PDI. The PDI's psychometric properties confirmed that it remains a reliable and valid instrument to measure delusional ideation in the general population. Consistent with the 40-item PDI, it was normally distributed, no sex differences were found, and there was an inverse relationship with age. Individual items were endorsed by just over one in four healthy adults. Although the deluded sample scored significantly higher, the range of scores overlapped considerably, with 11 percent of healthy adults scoring higher than the mean of the deluded group. As with our previous findings, the two samples were differentiated by their ratings on the distress, preoccupation, and conviction scales. These results suggest that these dimensions may be more important than the content of belief alone for placing an individual on the continuum between normal and delusional thinking.

Background: Persecutory delusions appear to involve abnormal attentional biases to threat-related information, particularly information related to the self. The present study aimed to investigate attentional biases to different types of perceived threat and changes in self-perception in response to exposure to such threat-related material., Method: Discrepancies between actual self, ideal self and perceived others' self-representations were assessed in three groups of participants; 13 people experiencing persecutory delusions, 11 people in a psychiatric comparison group, and 13 in a non-psychiatric comparison group. An adaptation of the emotional Stroop task was then used as an experimental manipulation of attentional bias to five different types of threat (sociotropic, autonomic, physical, ego threats from others, and self-directed ego threats). Self-discrepancies were then again assessed., Results: Before administration of the emotional Stroop task, there were no significant differences between the groups in terms of their self-actual:self-ideal and self-actual:other-actual discrepancies. However, after the administration of the Stroop task, significant differences between the clinical groups were observed, mirroring significant reductions in self-actual:self-ideal discrepancies and significant increases in self-actual:other-actual discrepancies in the paranoid participants., Conclusions: This paper is novel in repeating the assessment of self-discrepancies after the processing of threat-related information. These findings are consistent with Bentall, Kinderman, and Kaney's (1994) model of paranoid ideation and findings reported by Kinderman and Bentall (2000).

Objectives: Compassion‐focused therapy (CFT) is an evolution‐informed biopsychosocial approach that seeks to cultivate attachment and care motivational systems and their psychophysiological regulators. These can counteract some of the harmful effects of social threat, inferiority, shame, self‐criticism and depression, which are common in people with psychosis and undermine their well‐being, social trust and ability to feel safe. This study aimed to test the acceptability of a novel manualized individual CFT intervention for psychosis (CFTp). Design: A non‐concurrent, multiple‐baseline, case series design, with three phases: baseline, intervention and follow‐up. Methods: The 26‐session CFTp intervention was provided for a sample of eight people with distressing psychotic experiences and a psychosis‐related diagnosis. The study aimed to assess acceptability of CFTp and to test clinically reliable improvements while receiving the intervention, compared to a baseline period. Results: Seven of eight participants completed the therapy, and clinically reliable improvements were found at both the single‐case and group level of analysis. At the single‐case level, over half the participants showed improvements in depression (5/7), stress (5/7), distress (5/7), anxiety (4/7) and voices (3/5). One participant showed a deterioration in anxiety (1/7) and dissociation (1/7). At the group level (n = 7), there were significant improvements in depression, stress, distress, voices and delusions. The improvements in voices, delusions and distress were sustained at 6‐ to 8‐week follow‐up, but depression and stress dropped slightly to trend‐level improvements. Conclusions: CFTp is a feasible and acceptable intervention for psychosis, and further investigation is warranted with a randomized controlled trial. [ABSTRACT FROM AUTHOR]

Objective: The Cognitive Biases Questionnaire for psychosis (CBQp) was developed to capture 5 cognitive distortions (jumping to conclusions, intentionalising, catastrophising, emotional reasoning, and dichotomous thinking), which are considered important for the pathogenesis of psychosis. Vignettes were adapted from the Cognitive Style Test (CST),1 relating to “Anomalous Perceptions” and “Threatening Events” themes. Method: Scale structure, reliability, and validity were investigated in a psychosis group, and CBQp scores were compared with those of depressed and healthy control samples. Results: The CBQp showed good internal consistency and test-retest reliability. The 5 biases were not independent, with a 2-related factor scale providing the best fit. This structure suggests that the CBQp assesses a general thinking bias rather than distinct cognitive errors, while Anomalous Perception and Threatening Events theme scores can be used separately. Total CBQp scores showed good convergent validity with the CST, but individual biases were not related to existing tasks purporting to assess similar reasoning biases. Psychotic and depressed populations scored higher than healthy controls, and symptomatic psychosis patients scored higher than their nonsymptomatic counterparts, with modest relationships between CBQp scores and symptom severity once emotional disorders were partialled out. Anomalous Perception theme and Intentionalising bias scores showed some specificity to psychosis. Conclusions: Overall, the CBQp has good psychometric properties, although it is likely that it measures a different construct to existing tasks, tentatively suggested to represent a bias of interpretation rather than reasoning, judgment or decision-making processes. It is a potentially useful tool in both research and clinical arenas. [ABSTRACT FROM PUBLISHER]

Evidence suggests that negative schemas, mood and psychological flexibility are associated with delusional thinking. However, the temporal relationship of these variables has not been investigated. It is hypothesised that, in healthy populations, negative schemas will trigger delusional thinking through the mediating influence of negative mood. The strength of this association is predicted to be moderated by psychological flexibility. A total of 700 participants completed a survey assessing negative schemas, delusional thinking, mood, and psychological flexibility. All measures were re-administered six months later with a sub group of participants (204). Negative schemas significantly predicted higher rates of delusional thinking concurrently. Indirect effect testing revealed that the relationship between negative schemas and delusional thinking was partially mediated through anxiety, and that this indirect effect was moderated by psychological flexibility. Longitudinal cross-lag analysis showed that Time 1 anxiety predicted delusional ideation over time and the effect of Time 1 negative schemas on Time 2 delusional ideation was fully mediated by Time 2 anxiety. These results describe the processes by which negative schemas promote delusional thinking in healthy individuals. It highlights the potential of targeting anxiety and rigid coping styles in therapy to reduce the risk and impact of psychotic symptoms. [ABSTRACT FROM AUTHOR]

A growing body of evidence demonstrates that persistent positive symptoms, particularly delusions, can be improved by cognitive behaviour therapy for psychosis. Heightened perception and processing of threat are believed to constitute the genesis of delusions. The present study aimed to examine functional brain changes following cognitive behaviour therapy for psychosis. The study involved 56 outpatients with one or more persistent positive distressing symptoms of schizophrenia. Twenty-eight patients receiving cognitive behaviour therapy for psychosis for 6–8 months in addition to their usual treatment were matched with 28 patients receiving treatment as usual. Patients’ symptoms were assessed by a rater blind to treatment group, and they underwent functional magnetic resonance imaging during an affect processing task at baseline and end of treatment follow-up. The two groups were comparable at baseline in terms of clinical and demographic parameters and neural and behavioural responses to facial and control stimuli. The cognitive behaviour therapy for psychosis with treatment-as-usual group (22 subjects) showed significant clinical improvement compared with the treatment-as-usual group (16 subjects), which showed no change at follow-up. The cognitive behaviour therapy for psychosis with treatment-as-usual group, but not the treatment-as-usual group, showed decreased activation of the inferior frontal, insula, thalamus, putamen and occipital areas to fearful and angry expressions at treatment follow-up compared with baseline. Reduction of functional magnetic resonance imaging response during angry expressions correlated directly with symptom improvement. This study provides the first evidence that cognitive behaviour therapy for psychosis attenuates brain responses to threatening stimuli and suggests that cognitive behaviour therapy for psychosis may mediate symptom reduction by promoting processing of threats in a less distressing way. [ABSTRACT FROM AUTHOR]

Objective. To test the proposal that 'poor-me' (PM) and 'bad-me' (BM) paranoia can be differentiated in terms of (1) current emotional experience and presence of grandiose delusions and (2) early caregiving and threats to self-construction. Method. Participants experiencing persecutory delusions were separated into PM ( N= 21) and BM ( N= 15) groups on the basis of perceived deservedness of the persecution. The groups were compared on measures examining grandiose delusions, shame and depression, parental care, and threats of alienation and insecurity. Results. As predicted, BM patients scored higher on shame and depression, and lower on grandiose delusions, than PM patients. BM patients reported higher levels of parental overprotection, but PM patients were not characterized by neglect, and the groups did not differ in type of threat to self-construction. Conclusion. The two paranoia types were differentiated on symptomatic and emotional presentation, but predicted differences in early relationships and self-construction were not fully supported. [ABSTRACT FROM AUTHOR]

The Peters et al. Delusions Inventory (PDI) was designed to measure delusional ideation in the normal population, using the Present State Examination as a template. The multidimensionality of delusions was incorporated by assessing measures of distress, preoccupation, and conviction. Individual items were endorsed by one in four adults on average. No sex differences were found, and an inverse relationship with age was obtained. Good internal consistency was found, and its concurrent validity was confirmed by the percentages of common variance with three scales measuring schizotypy, magical ideation, and delusions. PDI scores up to 1 year later remained consistent, establishing its test-retest reliability. Psychotic inpatients had significantly higher scores, establishing its criterion validity. The ranges of scores between the normal and deluded groups overlapped considerably, consistent with the continuity view of psychosis. The two samples were differentiated by their ratings on the distress, preoccupation, and conviction scales, confirming the necessity for a multidimensional analysis of delusional thinking. Possible avenues of research using this scale and its clinical utility are highlighted. [ABSTRACT FROM PUBLISHER]