Association of the Jumping to Conclusions and Evidence Integration Biases With Delusions in Psychosis: A Detailed Meta-analysis

Neurocognitive performance and cognitive biases in young adults with schizotypal traits

Recent research suggests that neurocognitive deficits in patients with schizophrenia may increase the risk of developing cognitive biases. As such, we set out to determine this predictive relationship as it pertains to the development of a first-episode psychosis. We hypothesized that poorer performance in processing speed would be associated with jumping to conclusions and an externalizing bias. Poorer performance in working memory would be associated with belief inflexibility and jumping to conclusions, and poorer performance in attention would be associated with attention to threat. We hypothesized that all cognitive biases would be associated with subsyndromal positive symptoms, and schizotypal traits would moderate these relationships. Undergraduate students (N = 130) completed the Schizotypal Personality Questionnaire, DAVOS Assessment of Cognitive Biases, Community Assessment of Psychic Experiences, and a computerized neuropsychological assessment battery. Processing speed had a small effect on externalizing bias, which in turn affected subsyndromal positive symptoms. There was no moderating effect of schizotypal traits on externalizing bias, but it was significantly associated with subsyndromal positive symptoms. Only the externalizing bias was associated with subsyndromal positive symptomatology, which might be explained by a restricted range and reduced variance in performance as a result of using a university student sample. This is one of few studies that sought to explain the mechanism responsible for the development of subsyndromal positive symptoms in a healthy sample using self-report measures.

Action prediction in psychosis

Aberrant motor-sensory predictive functions have been linked to symptoms of psychosis, particularly reduced attenuation of self-generated sensations and misattribution of self-generated actions. Building on the parallels between prediction of self- and other-generated actions, this study aims to investigate whether individuals with psychosis also demonstrate abnormal perceptions and predictions of others' actions. Patients with psychosis and matched controls completed a two-alternative object size discrimination task. In each trial, they observed reaching actions towards a small and a large object, with varying levels of temporal occlusion ranging from 10% to 80% of movement duration. Their task was to predict the size of the object that would be grasped. We employed a novel analytic approach to examine how object size information was encoded and read out across progressive levels of occlusion with single-trial resolution. Patients with psychosis exhibited an overall pattern of reduced and discontinuous evidence integration relative to controls, characterized by a period of null integration up to 20% of movement duration, during which they did not read any size information. Surprisingly, this drop in accuracy in the initial integration period was not accompanied by a reduction in confidence. Difficulties in action prediction were correlated with the severity of negative symptoms and impaired functioning in social relationships.

Psychiatric burden in a cohort of adults with Niemann Pick type C disease: from psychotic symptoms to frontal lobe behavioral disorders

OBJECTIVES

To describe Niemann-Pick type C (NP-C) behavioral symptoms (focusing on psychotic symptoms) and its relation to frontal lobe functioning.

METHODS

We retrospectively reviewed medical charts of NP-C-patients followed in the Lysosomal Diseases reference center in Paris Pitié-Salpêtrière. We collected demographic data, psychiatric clinical manifestations, psychometric scales, and extended neuropsychological data including executive and behavioral frontal lobe functions evaluations.

RESULTS

Nineteen patients were included in the study with ten of them having experienced at least one acute psychotic episode, being inaugural for six of them. Most of the patients suffered from behavioral (15/17) and cognitive disorders (18/19) (including executive dysfunction (11/12), apathy (13/17), impaired social cognition (11/13) and stereotyped behaviors (5/10). For five patients, quality of life was significantly impaired by these abnormal behaviors. Concerning frontal neuropsychological evaluation, Facial emotion recognition was by far the most performed neuropsychological test (n = 8) and the score was always abnormal. It is noteworthy that psychotic symptoms were often drug resistant (8/9) and that Miglustat was associated with a better control of psychotic symptoms.

CONCLUSIONS

We report a high frequency of psychiatric symptoms in NP-C encompassing acute psychotic manifestations, often presenting early in the course of the disease with atypical features. We also report disabling behavioral manifestations related to frontal dysfunction.

Cognitive biases in first-episode psychosis with and without attention-deficit/hyperactivity disorder

Introduction

Psychotic disorders such schizophrenia and attention-deficit/hyperactivity disorder (ADHD) are neurodevelopmental disorders with social cognitive deficits. Specifically, biased interpretation of social information can result in interpersonal difficulties. Cognitive biases are prevalent in psychosis, but no previous study has investigated whether the type and severity of cognitive biases differ between subjects experiencing first-episode psychosis (FEP) with (FEP-ADHD⁺) and without ADHD (FEP-ADHD^-).

Methods

A total of 121 FEP outpatients at the Early Intervention Service of Reus were screened for childhood ADHD through the Diagnostic Interview for ADHD (DIVA). Cognitive biases were assessed by the Cognitive Biases Questionnaire for Psychosis (CBQp). CBQp scores of FEPs groups were compared with those of healthy controls (HCs) with an analysis of covariance. Spearman correlation analysis explored associations between CBQp scores and psychopathology.

Results

Thirty-one FEPs met the criteria for childhood ADHD and reported significantly more cognitive bias [median (interquartile range): 47 (38-56)] than FEP-ADHD^- [42 (37-48)] and HCs [38 (35.5-43)]. CBQp scores did not differ between FEP-ADHD-and HCs when adjusted for age and sex. After controlling for clinical differences, Intentionalising (F = 20.97; p < 0.001) and Emotional Reasoning biases (F = 4.17; p = 0.04) were more strongly associated with FEP-ADHD⁺ than FEP-ADHD^-. Cognitive biases were significantly correlated with positive psychotic symptoms in both groups but only with depressive symptoms in FEP-ADHD^- (r = 0.258; p = 0.03) and with poor functioning in FEP-ADHD⁺ (r = -0.504; p = 0.003).

Conclusion

Cognitive bias severity increased from HCs to FEP-ADHD-patients to FEP-ADHD⁺ patients. FEP-ADHD⁺ patients may be a particularly vulnerable group in which metacognitive targeted interventions are needed.

Relationships between cognitive biases, decision-making, and delusions

Multiple measures of decision-making under uncertainty (e.g. jumping to conclusions (JTC), bias against disconfirmatory evidence (BADE), win-switch behavior, random exploration) have been associated with delusional thinking in independent studies. Yet, it is unknown whether these variables explain shared or unique variance in delusional thinking, and whether these relationships are specific to paranoia or delusional ideation more broadly. Additionally, the underlying computational mechanisms require further investigation. To investigate these questions, task and self-report data were collected in 88 individuals (46 healthy controls, 42 schizophrenia-spectrum) and included measures of cognitive biases and behavior on probabilistic reversal learning and explore/exploit tasks. Of those, only win-switch rate significantly differed between groups. In regression, reversal learning performance, random exploration, and poor evidence integration during BADE showed significant, independent associations with paranoia. Only self-reported JTC was associated with delusional ideation, controlling for paranoia. Computational parameters increased the proportion of variance explained in paranoia. Overall, decision-making influenced by strong volatility and variability is specifically associated with paranoia, whereas self-reported hasty decision-making is specifically associated with other themes of delusional ideation. These aspects of decision-making under uncertainty may therefore represent distinct cognitive processes that, together, have the potential to worsen delusional thinking across the psychosis spectrum.

Computational mechanisms of belief updating in relation to psychotic-like experiences

Introduction

Psychotic-like experiences (PLEs) may occur due to changes in weighting prior beliefs and new evidence in the belief updating process. It is still unclear whether the acquisition or integration of stable beliefs is altered, and whether such alteration depends on the level of environmental and belief precision, which reflects the associated uncertainty. This motivated us to investigate uncertainty-related dynamics of belief updating in relation to PLEs using an online study design.

Methods

We selected a sample (n = 300) of participants who performed a belief updating task with sudden change points and provided self-report questionnaires for PLEs. The task required participants to observe bags dropping from a hidden helicopter, infer its position, and dynamically update their belief about the helicopter's position. Participants could optimize performance by adjusting learning rates according to inferred belief uncertainty (inverse prior precision) and the probability of environmental change points. We used a normative learning model to examine the relationship between adherence to specific model parameters and PLEs.

Results

PLEs were linked to lower accuracy in tracking the outcome (helicopter location) (β = 0.26 ± 0.11, p = 0.018) and to a smaller increase of belief precision across observations after a change point (β = -0.003 ± 0.0007, p < 0.001). PLEs were related to slower belief updating when participants encountered large prediction errors (β = -0.03 ± 0.009, p = 0.001). Computational modeling suggested that PLEs were associated with reduced overall belief updating in response to prediction errors (βPE = -1.00 ± 0.45, p = 0.028) and reduced modulation of updating at inferred environmental change points (βCPP = -0.84 ± 0.38, p = 0.023).

Discussion

We conclude that PLEs are associated with altered dynamics of belief updating. These findings support the idea that the process of balancing prior belief and new evidence, as a function of environmental uncertainty, is altered in PLEs, which may contribute to the development of delusions. Specifically, slower learning after large prediction errors in people with high PLEs may result in rigid beliefs. Disregarding environmental change points may limit the flexibility to establish new beliefs in the face of contradictory evidence. The present study fosters a deeper understanding of inferential belief updating mechanisms underlying PLEs.

The Effect of Situational Experiment Conditions on Hasty Decision Making in the 'Beads Task'

'Jumping to Conclusions', or hasty decision making, is widely studied within clinical and computational psychology. It is typically investigated using the 'beads task', a sequential information sampling paradigm, and defining one or two draws as jumping to conclusion. Situational experimental conditions, e.g., group vs. individual testing, abstract vs. cover story, show-up fee or course credit, frequently vary between studies. Little effort has been dedicated to investigating the potential effects of demand characteristics on hasty decision making. We explored this in four samples of participants (n = 336), in different situational experiment conditions, with two distinct variations of the beads task. An abstract 'Draws to Decision' (DtD) variant, and a cover story combined DtD and probabilistic inferences variant. Situational conditions did not have a significant effect on overall DtD for either variant. However, when using 'extreme scores' (DtD of 1 or 1 to 2) as a measure of hasty decision making, situational conditions had an effect for the abstract variant, with individual testing having the fewest hasty decision makers (DtD1: Mann-Whitney U = 2137.5, p = 0.02; DtD1-2: Mann-Whitney U = 2017.5, p < 0.01), but not for the cover story variant. Our results suggest that the abstract variant is more susceptible to test conditions, especially if a categorisation is used to classify hasty decisions. This does not imply that the cover story variant is better suited to capturing jumping to conclusions behaviour, but highlights the importance of mirroring the situational conditions between different samples. We recommend that testing conditions should be fully disclosed.

Can you trust this source? Advice taking in borderline personality disorder

Research suggests that patients with borderline personality disorder (BPD) share a range of cognitive biases with patients with psychosis. As the disorder often manifests in dysfunctional social interactions, we assumed associated reasoning styles would be exaggerated in a social setting. For the present study, we applied the Judge-Advisor System by asking participants to provide initial estimates of a person's age and presumed hostility based on a portrait photo. Afterwards, we presented additional cues/advice in the form of responses by anonymous previous respondents. Participants could revise their estimate, seek additional advice, or make a decision. Contrary to our preregistered hypothesis, patients with BPD (n = 38) performed similarly to healthy controls (n = 30). Patients sought the same number of pieces of advice, were equally confident, and used advice in similar ways to revise their estimates. Thus, patients with BPD did trust advice. However, patients gave higher hostility ratings to the portrayed persons. In conclusion, patients with BPD showed no cognitive biases in seeking, evaluating, and integrating socially provided information. While the study implies emotional rather than cognitive biases in the disorder, cognitive biases may still prove to be useful treatment targets in order to encourage delaying and reflecting on extreme emotional responses in social interactions.

Antipsychotics-induced improvement of cool executive function in individuals living with schizophrenia

Cool executive dysfunction is a crucial feature in people living with schizophrenia which is related to cognition impairment and the severity of the clinical symptoms. Based on electroencephalogram (EEG), our current study explored the change of brain network under the cool executive tasks in individuals living with schizophrenia before and after atypical antipsychotic treatment (before_TR vs. after_TR). 21 patients with schizophrenia and 24 healthy controls completed the cool executive tasks, involving the Tower of Hanoi Task (THT) and Trail-Marking Test A-B (TMT A-B). The results of this study uncovered that the reaction time of the after_TR group was much shorter than that of the before_TR group in the TMT-A and TMT-B. And the after_TR group showed fewer error numbers in the TMT-B than those of the before_TR group. Concerning the functional network, stronger DMN-like linkages were found in the before_TR group compared to the control group. Finally, we adopted a multiple linear regression model based on the change network properties to predict the patient's PANSS change ratio. Together, the findings deepened our understanding of cool executive function in individuals living with schizophrenia and might provide physiological information to reliably predict the clinical efficacy of schizophrenia after atypical antipsychotic treatment.

Bayesian reasoning with emotional material in patients with schizophrenia

Delusions are one of the most classical symptoms described in schizophrenia. However, despite delusions are often emotionally charged, they have been investigated using tasks involving non-affective material, such as the Beads task. In this study we compared 30 patients with schizophrenia experiencing delusions with 32 matched controls in their pattern of responses to two versions of the Beads task within a Bayesian framework. The two versions of the Beads task consisted of one emotional and one neutral, both with ratios of beads of 60:40 and 80:20, considered, respectively, as the “difficult” and “easy” variants of the task. Results indicate that patients showed a greater deviation from the normative model, especially in the 60:40 ratio, suggesting that more inaccurate probability estimations are more likely to occur under uncertainty conditions. Additionally, both patients and controls showed a greater deviation in the emotional version of the task, providing evidence of a reasoning bias modulated by the content of the stimuli. Finally, a positive correlation between patients’ deviation and delusional symptomatology was found. Impairments in the 60:40 ratio with emotional content was related to the amount of disruption in life caused by delusions. These results contribute to the understanding of how cognitive mechanisms interact with characteristics of the task (i.e., ambiguity and content) in the context of delusional thinking. These findings might be used to inform improved intervention programs in the domain of inferential reasoning.

Jumping to Conclusions and Its Associations With Psychotic Experiences in Preadolescent Children at Familial High Risk of Schizophrenia or Bipolar Disorder-The Danish High Risk and Resilience Study, VIA 11

BACKGROUND

The jumping to conclusions (JTC) bias, ie, making decisions based on inadequate evidence, is associated with psychosis in adults and is believed to underlie the formation of delusions. Knowledge on the early manifestations of JTC and its associations with psychotic experiences (PE) in children and adolescents is lacking.

DESIGN

Preadolescent children (mean age 11.9 y, SD 0.2) at familial high risk of schizophrenia (FHR-SZ, n = 169) or bipolar disorder (FHR-BP, n = 101), and controls (n = 173) were assessed with the Beads Task to examine JTC. The number of beads drawn before making a decision, "draws to decision" (DTD) was used as a primary outcome. PE were ascertained in face-to-face interviews. General intelligence was measured with Reynolds Intellectual Screening Test.

RESULTS

Children at FHR-SZ took fewer DTD than controls (4.9 vs 5.9, Cohen's d = 0.31, P = .004). Differences were attenuated when adjusting for IQ (Cohen's d = 0.24, P = .02). Higher IQ was associated with a higher number of DTD (B = 0.073, P < .001). Current subclinical delusions compared with no PE were associated with fewer DTD in children at FHR-SZ (P = .04) and controls (P < .05). Associations between delusions and DTD were nullified when accounting for IQ.

CONCLUSIONS

JTC marks familial risk of psychosis in preadolescence, not reducible to general intelligence. JTC is associated with subclinical delusions, but this may be an expression of intellectual impairment. Future studies should establish temporality between JTC and delusion formation and examine JTC as a target for early intervention.

Rethinking delusions: A selective review of delusion research through a computational lens

Delusions are rigid beliefs held with high certainty despite contradictory evidence. Notwithstanding decades of research, we still have a limited understanding of the computational and neurobiological alterations giving rise to delusions. In this review, we highlight a selection of recent work in computational psychiatry aimed at developing quantitative models of inference and its alterations, with the goal of providing an explanatory account for the form of delusional beliefs in psychosis. First, we assess and evaluate the experimental paradigms most often used to study inferential alterations in delusions. Based on our review of the literature and theoretical considerations, we contend that classic draws-to-decision paradigms are not well-suited to isolate inferential processes, further arguing that the commonly cited 'jumping-to-conclusion' bias may reflect neither delusion-specific nor inferential alterations. Second, we discuss several enhancements to standard paradigms that show promise in more effectively isolating inferential processes and delusion-related alterations therein. We further draw on our recent work to build an argument for a specific failure mode for delusions consisting of prior overweighting in high-level causal inferences about partially observable hidden states. Finally, we assess plausible neurobiological implementations for this candidate failure mode of delusional beliefs and outline promising future directions in this area.

SlowMo therapy, a new digital blended therapy for fear of harm from others: An account of therapy personalisation within a targeted intervention

OBJECTIVES

SlowMo therapy is a pioneering blended digital therapy for paranoia, augmenting face-to-face therapy with an interactive 'webapp' and a mobile app. A recent large-scale trial demonstrated small-moderate effects on paranoia alongside improvements in self-esteem, worry, well-being and quality of life. This paper provides a comprehensive account of therapy personalisation within this targeted approach.

DESIGN

Case examples illustrate therapy delivery and descriptive data are presented on personalised thought content.

METHOD

Thought content was extracted from the webapp (n = 140 participants) and coded using newly devised categories: Worries: (1) Persecutory, (2) Negative social evaluation, (3) Negative self-concept, (4) Loss/life stresses, (5) Sensory-perceptual experiences and (6) Health anxieties. Safer thoughts: (1) Safer alternative (specific alternatives to worries), (2) Second-wave (generalised) coping, (3) Positive self-concept, (4) Positive activities and (5) Third-wave (mindfulness-based) coping. Data on therapy fidelity are also presented.

RESULTS

Worries: 'Persecutory' (92.9% of people) and 'Negative social evaluation' (74.3%) were most common. 'General worries/ life stresses' (31.4%) and 'Negative self-concept' (22.1%) were present in a significant minority; 'Health anxieties' (10%) and 'Sensory-perceptual' (10%) were less common. Safer thoughts: 'Second-wave (general) coping' (85%), 'Safer alternatives' (76.4%), 'Positive self-concept' (65.7%) and 'Positive activities' (64.3%) were common with 'Third-wave' (mindfulness) coping observed for 30%. Fidelity: Only three therapy withdrawals were therapy related. Session adherence was excellent (mean = 15.2/16; SD = 0.9). Behavioural work was conducted with 71% of people (119/168).

CONCLUSION

SlowMo therapy delivers a targeted yet personalised approach. Potential mechanisms of action extend beyond reasoning. Implications for cognitive models of paranoia and causal interventionist approaches are discussed.

The relationship between jumping to conclusions and social cognition in first-episode psychosis

Jumping to conclusions (JTC) and impaired social cognition (SC) affect the decoding, processing, and use of social information by people with psychosis. However, the relationship between them had not been deeply explored within psychosis in general, and in first-episode psychosis (FEP) in particular. Our aim was to study the relationship between JTC and SC in a sample with FEP. We conducted a cross-sectional study with 121 patients with FEP, with measures to assess JTC (easy, hard, and salient probability tasks) and SC (emotional recognition, attributional style, and theory of mind). We performed Student's t-test and logistic regression in order to analyse these associations.We found a statistically significant and consistent relationship of small-moderate effect size between JTC (all three tasks) and impaired emotional recognition. Also, our results suggest a relationship between JTC and internal attributions for negative events. Relationships between JTC and theory of mind were not found. These results highlight the importance of psychological treatments oriented to work on a hasty reasoning style and on improving processing of social information linked to emotional recognition and single-cause attributions.

Verbal manifestations of metacognitive and social cognitive operations in patients with schizophrenia who received metacognitive training

The study investigates with inductive content analysis the verbal manifestations of schizophrenia patients, their utterances within the theory of mind modules of Metacognitive Training. Participants were recruited via psychiatrists’ verbal referrals. Four small groups were formed, two of which consented to the audio recording of their sessions. Only the sessions of these two groups of five and four patients respectively were investigated. As two participants dropped out, the verbalisations of seven participants were eventually analysed. All patients had schizophrenia diagnosis (mean age: 43 years, male: two, female: five). The verbal contents were transcribed, then two independent coders did the categorisation of the content; investigator triangulation ensured the reliability and validity of the study. As a result, a five-level hierarchy of cognitive operations was revealed in a bottom-up way. Patients attempted to interpret not only facial expressions but expressive movements, too, during emotion recognition. When deducing the state of others, patients sought contextual information; moreover, the burden of the illness and stigmatisation became easy to share. No signs of awareness of the consequences of the inferred states were found regarding future adjustment. Our hierarchical structure was consistent with related literature, and the specificities of cognitive operations of participants were also revealed.

Association Between Wisdom and Psychotic-Like Experiences in the General Population: A Cross-Sectional Study

INTRODUCTION

Wisdom has been empirically researched as a complex psychological characteristic that is associated with many mental health outcomes. However, its association with psychotic-like experiences (PLEs) remains unclear. This is the first work to assess wisdom, explore its association with PLEs, and test its moderating effect on the relation between the frequency of PLEs and their associated distress in the general population.

METHODS

From January 29th to February 5th, 2021, our online self-administered survey recruited 927 participants (ages 14 to 65) from thirteen Chinese provinces. Convenience sampling was employed. We measured wisdom with the 12-item three-dimensional wisdom scale (3D-WS-12) and PLEs with the 15-item positive subscale of the Community Assessment of Psychic Experiences (CAPE-P15).

RESULTS

Using the cut-off value of 1.47 in the mean frequency score, we divided our participants into high-PLEs group (188, 22.1%) and low-PLEs group (663, 77.9%). Three-dimensional wisdom score was decreased in the high-PLEs group compared to the low-PLEs group (Kruskal-Wallis t = 59.9, p < 0.001). Wisdom was associated with less frequent PLEs (Spearman's rho = -0.21, p < 0.01) and lower distress related to PLEs (Spearman's rho = -0.28) in the high-PLEs group (all above p < 0.001), which were replicated in the low-PLEs group. Notably, wisdom significantly attenuated the distress associated with PLEs [coefficient = -0.018, Bootstrap 95% CI (-0.029, -0.008)], but only in the low-PLEs group.

CONCLUSION

Our results implicated that wisdom could protect individuals from distressful subclinical psychotic symptoms and wiser individuals have better general mental health.

Is intuition allied with jumping to conclusions in decision-making? An intensive longitudinal study in patients with delusions and in non-clinical individuals

Research suggests that a jumping-to-conclusions (JTC) bias, excessive intuition, and reduced analysis in information processing may favor suboptimal decision-making, both in non-clinical and mentally disordered individuals. The temporal relationship between processing modes and JTC bias, however, remains unexplored. Therefore, using an experience sampling methodology (ESM) approach, this study examines the temporal associations between intuitive/analytical information processing, JTC bias, and delusions in non-clinical individuals and patients with schizophrenia. Specifically, we examine whether a high use of intuitive and/or a low use of analytical processing predicts subsequent JTC bias and paranoid conviction. In a smartphone-based ESM study, participants will be prompted four times per day over three consecutive days to answer questionnaires designed to measure JTC bias, paranoid conviction, and preceding everyday-life intuition/analysis. Our hierarchical data will be analyzed using multilevel modelling for hypothesis testing. Results will further elucidate the role of aberrant human reasoning, particularly intuition, in (non-)clinical delusions and delusion-like experiences, and also inform general information processing models.

Neural Correlates of Aberrant Salience and Source Monitoring in Schizophrenia and At-Risk Mental States-A Systematic Review of fMRI Studies

Cognitive biases are an important factor contributing to the development and symptom severity of psychosis. Despite the fact that various cognitive biases are contributing to psychosis, they are rarely investigated together. In the current systematic review, we aimed at investigating specific and shared functional neural correlates of two important cognitive biases: aberrant salience and source monitoring. We conducted a systematic search of fMRI studies of said cognitive biases. Eight studies on aberrant salience and eleven studies on source monitoring were included in the review. We critically discussed behavioural and neuroimaging findings concerning cognitive biases. Various brain regions are associated with aberrant salience and source monitoring in individuals with schizophrenia and the risk of psychosis. The ventral striatum and insula contribute to aberrant salience. The medial prefrontal cortex, superior and middle temporal gyrus contribute to source monitoring. The anterior cingulate cortex and hippocampus contribute to both cognitive biases, constituting a neural overlap. Our review indicates that aberrant salience and source monitoring may share neural mechanisms, suggesting their joint role in producing disrupted external attributions of perceptual and cognitive experiences, thus elucidating their role in positive symptoms of psychosis. Account bridging mechanisms of these two biases is discussed. Further studies are warranted.

Cognitive Biases Questionnaire for Psychosis (CBQp): Spanish Validation and Relationship With Cognitive Insight in Psychotic Patients

Introduction: Cognitive biases are key factors in the development and persistence of delusions in psychosis. The Cognitive Biases Questionnaire for Psychosis (CBQp) is a new self-reported questionnaire of 30 relevant situations to evaluate five types of cognitive biases in psychosis. In the context of the validation of the Spanish version of the CBQp, our objectives were to (1) analyze the factorial structure of the questionnaire with a confirmatory factor analysis (CFA), (2) relate cognitive biases with a widely used scale in the field of delusion cognitive therapies for assessing metacognition, specifically, Beck's Cognitive Insight Scale (BCIS) (1), and, finally, (3) associate cognitive biases with delusional experiences, evaluated with the Peters Delusions Inventory (PDI) (2). Materials and Methods: An authorized Spanish version of the CBQp, by a translation and back-translation procedure, was obtained. A sample of 171 patients with different diagnoses of psychoses was included. A CFA was used to test three different construct models. Associations between CBQp biases, the BCIS, and the PDI were made by correlation and mean differences. Comparisons of the CBQp scores between a control group and patients with psychosis were analyzed. Results: The CFA showed comparative fit index (CFI) values of 0.94 and 0.95 for the models with one, two, and five factors, with root mean square error of approximation values of 0.031 and 0.029. The CBQp reliability was 0.87. Associations between cognitive biases, self-certainty, and cognitive insight subscales of the BCIS were found. Similarly, associations between total punctuation, conviction, distress, and concern subscales of the PDI were also found. When compared with the group of healthy subjects, patients with psychoses scored significantly higher in several cognitive biases. Conclusion: Given the correlation between biases, a one-factor model might be more appropriate to explain the scale's underlying construct. Biases were associated with a greater frequency of delusions, distress, conviction, and concern as well as worse cognitive insight in patients with psychosis.

Inflexibility in Reasoning: Comparisons of Cognitive Flexibility, Explanatory Flexibility, and Belief Flexibility Between Schizophrenia and Major Depressive Disorder

Introduction: Inflexibility in reasoning has been suggested to contribute to psychiatric disorders, such as explanatory flexibility in depression and belief flexibility in schizophrenia. However, studies tended to examine only one of the flexibility constructs, which could be related to each other, within a single group of patients. As enhancing flexibility in thinking has become one of the psychological treatment goals across disorders, this study aimed to examine three constructs of flexibility (cognitive flexibility, explanatory flexibility, and belief flexibility) in two psychiatric groups. Methods: We compared three groups of participants: (i) 56 outpatients with a schizophrenia-spectrum disorder and active delusions, (ii) 57 outpatients with major depressive disorder and at least a moderate level of depression, and (iii) 30 healthy controls. Participants were assessed on symptom severity and flexibility, using the Trail-Making Task, the Attributional Style Questionnaire, the Maudsley Assessment of Delusions Scale (MADS) and the Bias Against Disconfirmatory Evidence (BADE) Task. Results: Cognitive flexibility was reduced in the two clinical groups compared to controls. Explanatory flexibility was comparable across groups. The three groups differed in belief flexibility measured by MADS but not by the BADE task. Response to hypothetical contradiction was reduced in the delusion group than the other two groups, and the ability to generate alternative explanations was reduced in the delusion group than healthy controls. Discussion: We found an effect of diagnosis on cognitive flexibility, which might be confounded by differences in intellectual functioning. Reduced belief flexibility tended to be specific to delusions.

Paranoia and Grandiosity in the General Population: Differential Associations With Putative Causal Factors

Worry, negative self-beliefs, and sleep disturbance have been identified as contributory factors to the onset, maintenance, and severity of paranoia. We tested the specificity of these contributory factors to paranoia compared to grandiosity, a different type of delusional ideation. Data were used from 814 adults from the Nathan Kline Institute-Rockland (NKI-Rockland) study, a general population dataset. Paranoid and grandiose delusional ideation was assessed using the Peters Delusions Inventory (PDI-21) and correlated with self-reported worry (n = 228), negative self-beliefs (n = 485), and sleep quality (n = 655). Correlations were compared using Fisher's r-to-z transform to examine whether the magnitude of relationships differed by delusion type. Paranoia was significantly associated with worry, negative self-belief, and sleep quality. Grandiosity demonstrated significantly weaker relationships with worry and negative self-beliefs. Relationships with sleep quality were similar. We replicate previous reports that worry, negative self-beliefs and sleep quality are associated with paranoid ideation in the general population. We extend these findings by demonstrating that these contributory factors, particularly worry and negative self-beliefs, are associated with paranoid ideation to a greater extent than grandiosity. This suggests a degree of specificity of contributory factors to different types of delusional thinking, supporting the pursuit of specific psychological models and treatments for each delusion type.

Probing the Hypersalience Hypothesis-An Adapted Judge-Advisor System Tested in Individuals With Psychotic-Like Experiences

Individuals with psychotic-like experiences and psychosis gather and use information differently than controls; in particular they seek and rely on less information or over-weight currently available information. A new paradigm, the judge-advisor system, has previously been used to investigate these processes. Results showed that psychosis-prone individuals tend to seek less advice but at the same time use the available advice more. Some theoretical models, like the hypersalience of evidence-matching hypothesis, predict that psychosis-prone individuals weight recently available information to a greater extent and thus provide an explanation for increased advice-weighting scores in psychosis-prone individuals. To test this model, we adapted the previously used judge-advisor system by letting participants receive consecutively multiple pieces of advice. To meet this aim, we recruited a large MTurk community sample (N = 1,396), which we split in a group with high levels of psychotic-like experiences (at least 2 SD above the mean, n = 80) and a group with low levels of psychotic-like experiences (maximum 0.5 SD above the mean, n = 1,107), using the Community Assessment of Psychic Experiences' positive subscale. First, participants estimated five people's age based on photographs. Then, they received consecutive advice in the form of manipulated age estimates by allegedly previous participants, with outliers in some trials. After each advice, participants could adjust their estimate. This procedure allowed us to investigate how participants weighted each currently presented advice. In addition to being more confident in their final estimates and in line with our preregistered hypothesis, participants with more frequent psychotic-like experiences did weight currently available advice more than participants with less frequent psychotic-like experiences. This effect was especially pronounced in response to outliers, as fine-grained post-hoc analysis suggested. Result thus support models predicting an overcorrection in response to new incoming information and challenges an assumed general belief inflexibility in people with psychotic experiences.

Reduced Jumping to Conclusion Bias after Experimentally Induced Enhancement of Subjective Body Boundaries in Psychosis

INTRODUCTION

A disturbed sense of self is frequently discussed as an etiological factor for delusion symptoms in psychosis. Phenomenological approaches to psychopathology posit that lacking the sense that the self is localized within one's bodily boundaries (disembodiment) is one of the core features of the disturbed self in psychosis. The present study examines this idea by experimentally manipulating the sense of bodily boundaries.

METHODS

Seventy-three patients with psychosis were randomly assigned to either a 10-min, guided self-massage in the experimental group (EG) to enhance the sense of bodily boundaries or a control group (CG), which massaged a fabric ring. Effects on an implicit measure (jumping to conclusion bias; JTC) and an explicit measure (Brief State Paranoia Checklist; BSPC) of delusion processes were assessed. The JTC measures the tendency to make a decision with little evidence available, and the BSPC explicitly measures the approval of paranoid beliefs.

RESULTS

Patients in the EG showed a lower JTC (M = 4.11 draws before decision) than the CG (M = 2.43; Cohen's d = 0.64). No significant difference in the BSPC was observed.

DISCUSSION/CONCLUSION

Our results indicate that enhancing the sense of body boundaries through a self-massage can reduce an implicit bias associated with delusional ideation and correspondingly support the idea that disembodiment might be a relevant factor in the formation of psychotic symptoms.

Derationalizing Delusions

Because of the traditional conceptualization of delusion as “irrational belief,” cognitive models of delusions largely focus on impairments to domain-general reasoning. Nevertheless, current rationality-impairment models do not account for the fact that (a) equivalently irrational beliefs can be induced through adaptive social cognitive processes, reflecting social integration rather than impairment; (b) delusions are overwhelmingly socially themed; and (c) delusions show a reduced sensitivity to social context both in terms of how they are shaped and how they are communicated. Consequently, we argue that models of delusions need to include alteration to coalitional cognition—processes involved in affiliation, group perception, and the strategic management of relationships. This approach has the advantage of better accounting for both content (social themes) and form (fixity) of delusion. It is also supported by the established role of mesolimbic dopamine in both delusions and social organization and the ongoing reconceptualization of belief as serving a social organizational function.

Glyceryl trinitrate in first-episode psychosis unmedicated with antipsychotics: A randomised controlled pilot study

BACKGROUND

There is a pressing need for new classes of treatment for psychosis. A key therapeutic target for novel compounds is the NMDA receptor, which may be modulated by nitric oxide donors such as sodium nitroprusside (SNP). Recent studies of SNP in patients with psychosis have mixed results, and the drug has to be administered intravenously. Glyceryl trinitrate (GTN) is a well-established cardiovascular medicine that is also a nitric oxide donor, and can be given orally.

AIMS

We explored the safety and potential effects of GTN in unmedicated patients with a first episode of psychosis.

METHODS

This was a single-centre, randomised, double-blind, placebo-controlled trial from December 2016 to April 2019 (ClinicalTrials.gov identifier: NCT02906553). Patients received 3 × sprays of GTN or placebo for three consecutive days, and were re-assessed on Days 1, 2, 3 and 7. The primary outcome was cognition (Jumping to Conclusions task), secondary outcomes were symptoms (Positive and Negative Syndrome Scale (PANSS)), verbal memory (Hopkins Verbal Learning task), and mood (Bond-Lader Visual Analogue Scales).

RESULTS

Nineteen patients were randomised, and 13 participants were included in the analyses. Compared with placebo, GTN was well tolerated, but was not associated with significant effects on cognition, symptoms, or mood. Bayesian statistics indicate that our results were 2× more likely under the null hypothesis than the alternative hypothesis, providing anecdotal evidence that GTN does not improve psychotic symptoms.

CONCLUSIONS

We found no indication of an effect of GTN on symptoms of psychosis or cognition.

Examining associations between two different jumping to conclusions scores with positive schizotypy and recent distress

Introduction: Jumping to conclusions is associated with delusions. It is unclear whether positive schizotypy, which refers to delusion-like and hallucination-like symptoms, is associated with jumping to conclusions. Relatedly, the relative validity of two jumping to conclusions scores, extreme responding and draws to decision, is unclear, particularly whether extreme responding (responding after one or two draws) reflects the same bias as decreased draws to decision on non-extreme responding trials.Methods: Extreme positive schizotypy individuals with increased psychosis risk (n = 69) and controls (n = 95) completed the Probabilistic Reasoning Task and reported on recent distress, which was previously associated with jumping to conclusions. We calculated extreme responding, draws to decision (number of draws), and draws to decision/non-extreme responding (number of draws on trials with three or more draws).Results: Positive schizotypy was associated with extreme responding, but not draws to decision/non-extreme responding. Furthermore, draws to decision and draws to decision/non-extreme responding were associated with recent distress, whereas extreme responding was not.Conclusion: Positive schizotypy was specifically associated with extreme responding and not draws to decision/non-extreme responding, which suggests that the nature of extreme responding and of draws to decision might be different. This could have relevance for assessing and treating jumping to conclusions.

Placing Cognitive Rigidity in Interpersonal Context in Psychosis: Relationship With Low Cognitive Reserve and High Self-Certainty

Introduction: People with psychosis show impairments in cognitive flexibility, a phenomenon that is still poorly understood. In this study, we tested if there were differences in cognitive and metacognitive processes related to rigidity in patients with psychosis. We compared individuals with dichotomous interpersonal thinking and those with flexible interpersonal thinking. Methods: We performed a secondary analysis using two groups with psychosis, one with low levels of dichotomous interpersonal thinking (n = 42) and the other with high levels of dichotomous interpersonal thinking (n = 43). The patients were classified by splitting interpersonal dichotomous thinking (measured using the repertory grid technique) to the median. The groups were administered a sociodemographic questionnaire, a semi-structured interview to assess psychotic symptoms [Positive and Negative Syndrome Scale (PANSS)], a self-report of cognitive insight [Beck Cognitive Insight Scale (BCIS)], neurocognitive tasks [Wisconsin Card Sorting Test (WCST) and Wechsler Adult Intelligence Scale (WAIS)], and the repertory grid technique. We used a logistic regression model to test which factors best differentiate the two groups. Results: The group with high dichotomous interpersonal thinking had earlier age at onset of the psychotic disorder, higher self-certainty, impaired executive functioning, affected abstract thinking, and lower estimated cognitive reserve than the group with flexible thinking. According to the logistic regression model, estimated cognitive reserve and self-certainty were the variables that better differentiated between the two groups. Conclusion: Cognitive rigidity may be a generalized bias that affects not only neurocognitive and metacognitive processes but also the sense of self and significant others. Patients with more dichotomous interpersonal thinking might benefit from interventions that target this cognitive bias on an integrative way and that is adapted to their general level of cognitive abilities.

Functional Brain Networks Underlying Evidence Integration and Delusions in Schizophrenia

Integrating evidence that contradicts a belief is a fundamental aspect of belief revision and is closely linked to delusions in schizophrenia. In a previous functional magnetic resonance imaging (fMRI) study on healthy individuals, we identified functional brain networks underlying evidence integration as visual attention network (VsAN; dorsal anterior cingulate cortex, insula, occipital regions), default-mode network (DMN), and cognitive evaluation network (CEN; orbitofrontal cortex, inferior frontal gyrus, parietal cortex). In the current clinical fMRI study, we compared network-based activity during evidence integration between healthy controls (n = 41), nondelusional (n = 37), and delusional (n = 33) patients with schizophrenia, and related this activity to cognitive processing involved in evidence integration measured outside the scanner. Task-induced coordinated activation was measured using group-constrained principal component analysis for fMRI. Increased VsAN activation, reduced DMN deactivation, and reduced CEN activation were observed for schizophrenia, with this pattern being most pronounced for the delusional group. Importantly, poor evidence integration comprehensively measured outside the scanner was significantly associated with increased VsAN activation and reduced DMN deactivation when processing confirmatory evidence, and with reduced CEN activation when processing disconfirmatory evidence. This is the first comprehensive study of the functional brain networks associated with evidence integration in schizophrenia and highlights how an imbalance of functional brain networks responding to confirmatory and disconfirmatory evidence may underlie delusions in schizophrenia.

The Mediating Role of Stress in the Relationship Between Attention to Threat Bias and Psychotic-Like Experiences Depends on Coping Strategies

AIM

Recent studies have provided evidence that enhanced stress level is associated with the increase of psychotic symptoms in both clinical and non-clinical populations. It has also been demonstrated that cognitive biases contribute to psychotic experiences. However, it remains unclear whether the effect of cognitive biases and perceived stress on psychotic-like experiences (PLEs) is influenced by coping methods. In the present study we examined whether the relationship linking cognitive biases with PLEs is mediated by the level of stress and whether particular coping methods modify the relationship between stress and PLEs.

METHODS

The study sample consisted of 290 non-clinical subjects; study variables were assessed by questionnaires. Moderated mediation analyses were conducted.

RESULTS

Perceived stress was found to serve as a partial mediator in the relationship linking attention to threat (ATB) and external attribution biases (ETB) with psychotic-like experiences. Also, moderated mediation analysis revealed that the indirect effect of attention to threat bias on positive and depressive symptoms of psychotic-like experiences via perceived stress was stronger at higher levels of distraction seeking coping. Moreover, the indirect effect of ATB on depressive symptoms was moderated by task-oriented coping and emotion-oriented coping. Task-oriented coping also moderated the indirect effect of ETB on depression.

CONCLUSION

The findings imply that both perceived stress and coping styles are important factors affecting the association between cognitive biases and psychotic-like experiences.

Stress and cognitive biases in schizotypy: A two-site study of bias against disconfirmatory evidence and jumping to conclusions

The dysfunctional cognitive and reasoning biases which underpin psychotic symptoms are likely to present prior to the onset of a diagnosable disorder and should therefore be detectable along the psychosis continuum in individuals with schizotypal traits. Two reasoning biases, Bias Against Disconfirmatory Evidence (BADE) and Jumping to Conclusions (JTC), describe how information is selected and weighed under conditions of uncertainty during decision making. It is likely that states such as elevated stress exacerbates JTC and BADE in individuals with high schizotypal traits vulnerable to displaying these information gathering styles. Therefore, we evaluated whether stress and schizotypy interacted to predict these reasoning biases using separate samples from the US (JTC) and England (BADE). Generally speaking, schizotypal traits and stress were not independently associated with dysfunctional reasoning biases. However, across both studies, the interaction between schizotypy traits and stress significantly predicted reasoning biases such that increased stress was associated with increased reasoning biases, but only for individuals low in schizotypal traits. These patterns were observed for positive schizotypal traits (in both samples), for negative traits (in the England sample only), but not for disorganization traits. For both samples, our findings suggest that the presence of states such as stress is associated with, though not necessarily dysfunctional, reasoning biases in individuals with low schizotypy. These reasoning biases seemed, in some ways, relatively immutable to stress in individuals endorsing high levels of positive schizotypal traits.

Effects of Metacognitive Training on Cognitive Insight in a Sample of Patients with Schizophrenia

Metacognitive training (MCT) is a group intervention that addresses cognitive biases and distortions that could help maintain delusions and hallucinations in people with schizophrenia. This program has proven its effectiveness in reducing the symptoms, but its impact on cognitive insight has scarcely been investigated. Therefore, the aim of the study was to assess the program’s impact on cognitive insight in patients with long-term schizophrenia. A sample of 22 patients with schizophrenia was divided into two groups: one received 16 sessions of MCT (n = 11), while the other received the usual treatment (n = 11). They were assessed using the Beck Cognitive Insight Scale which measures two components, self-reflection and self-certainty, and the Positive and Negative Syndrome Scale (PANSS). The experimental group showed high levels of adherence, an increase in self-reflection, and a decrease in self-assurance levels as hypothesized. We found statistically significant differences between the control and experimental groups in excitation, hostility, positive symptomatology total score, hallucinatory behavior, and suspicion. In the usual treatment group, a non-significant decrease in positive symptoms was also observed. The findings showed that the implementation of the MCT program in real clinical settings can contribute to an improvement in the metacognitive ability and symptomatology of people with schizophrenia.

Dual-process theory, conflict processing, and delusional belief

Many reasoning biases that may contribute to delusion formation and/or maintenance are common in healthy individuals. Research indicating that reasoning in the general population proceeds via analytic processes (which depend upon working memory and support hypothetical thought) and intuitive processes (which are autonomous and independent of working memory) may therefore help uncover the source of these biases. Consistent with this possibility, recent studies imply that impaired conflict processing might reduce engagement in analytic reasoning, thereby producing reasoning biases and promoting delusions in individuals with schizophrenia. Progress toward understanding this potential pathway to delusions is currently impeded by ambiguity about whether any of these deficits or biases is necessary or sufficient for the formation and maintenance of delusions. Resolving this ambiguity requires consideration of whether particular cognitive deficits or biases in this putative pathway have causal primacy over other processes that may also participate in the causation of delusions. Accordingly, the present manuscript critically evaluates whether impaired conflict processing is the primary initiating deficit in the generation of reasoning biases that may promote the development and/or maintenance of delusions. Suggestions for future research that may elucidate mechanistic pathways by which reasoning deficits might engender and maintain delusions are subsequently offered.

A distinct inferential mechanism for delusions in schizophrenia

Delusions, a core symptom of psychosis, are false beliefs that are rigidly held with strong conviction despite contradictory evidence. Alterations in inferential processes have long been proposed to underlie delusional pathology, but previous attempts to show this have failed to yield compelling evidence for a specific relationship between inferential abnormalities and delusional severity in schizophrenia. Using a novel, incentivized information-sampling task (a modified version of the beads task), alongside well-characterized decision-making tasks, we sought a mechanistic understanding of delusions in a sample of medicated and unmedicated patients with schizophrenia who exhibited a wide range of delusion severity. In this novel task, participants chose whether to draw beads from one of two hidden jars or to guess the identity of the hidden jar, in order to minimize financial loss from a monetary endowment, and concurrently reported their probability estimates for the hidden jar. We found that patients with higher delusion severity exhibited increased information seeking (i.e. increased draws-to-decision behaviour). This increase was highly specific to delusion severity as compared to the severity of other psychotic symptoms, working-memory capacity, and other clinical and socio-demographic characteristics. Delusion-related increases in information seeking were present in unmedicated patients, indicating that they were unlikely due to antipsychotic medication. In addition, after adjusting for delusion severity, patients as a whole exhibited decreased information seeking relative to healthy individuals, a decrease that correlated with lower socioeconomic status. Computational analyses of reported probability estimates further showed that more delusional patients exhibited abnormal belief updating characterized by stronger reliance on prior beliefs formed early in the inferential process, a feature that correlated with increased information seeking in patients. Other decision-making parameters that could have theoretically explained the delusion effects, such as those related to subjective valuation, were uncorrelated with both delusional severity and information seeking among the patients. In turn, we found some preliminary evidence that subjective valuation (rather than belief updating) may explain group differences in information seeking unrelated to delusions. Together, these results suggest that abnormalities in belief updating, characterized by stronger reliance on prior beliefs formed by incorporating information presented earlier in the inferential process, may be a core computational mechanism of delusional ideation in psychosis. Our results thus provide direct empirical support for an inferential mechanism that naturally captures the characteristic rigidity associated with delusional beliefs.

An evolutionary perspective on paranoia

Paranoia is the most common symptom of psychosis but paranoid concerns occur throughout the general population. Here, we argue for an evolutionary approach to paranoia across the spectrum of severity that accounts for its complex social phenomenology - including the perception of conspiracy and selective identification of perceived persecutors - and considers how it can be understood in light of our evolved social cognition. We argue that the presence of coalitions and coordination between groups in competitive situations could favour psychological mechanisms that detect, anticipate and avoid social threats. Our hypothesis makes testable predictions about the environments in which paranoia should be most common as well as the developmental trajectory of paranoia across the lifespan. We suggest that paranoia should not solely be viewed as a pathological symptom of a mental disorder but also as a part of a normally-functioning human psychology.

Individualized Metacognitive Training (MCT+) Reduces Delusional Symptoms in Psychosis: A Randomized Clinical Trial

Individualized metacognitive training (MCT+) is a novel psychotherapy that has been designed to specifically target delusional beliefs in people with psychosis. It works by developing an awareness of the implausible content of delusional beliefs, while also targeting the cognitive biases that contribute to their formation and maintenance. It was expected that MCT+ would lead to significantly greater reductions in delusional severity compared to a cognitive remediation (CR) active control condition. A total of 54 patients with a schizophrenia spectrum disorder and active delusions were randomized into four 2-hourly sessions of MCT+ (n = 27) or CR (n = 27). All participants completed posttreatment assessment, and only 2 participants did not complete 6-month follow-up assessment, resulting in MCT+ (n = 26) and CR (n = 26) for final analysis. The primary outcome measures of delusional and positive symptom severity were assessed rater-blind; secondary outcome assessment was non-blinded and included clinical and cognitive insight, the jumping to conclusions (JTC) bias, and cognitive functioning. Participants in the MCT+ condition showed significant reductions in delusional and overall positive symptom severity (large effect) and improved clinical insight (moderate effect) relative to CR controls. In contrast, CR controls showed moderate improvement in problem-solving ability relative to MCT+, but no other cognitive domain. Importantly, these findings were maintained at 6-month follow-up. The study adds further efficacy to the MCT program, and suggests that even brief psychotherapy can help to ameliorate the symptoms of psychosis.

Fast and slow thinking in distressing delusions: A review of the literature and implications for targeted therapy

The recent literature on reasoning biases in psychosis and delusions is reviewed. The state-of-the-art knowledge from systematic reviews and meta-analyses on the evidence for jumping to conclusions is briefly summarised, before a fuller discussion of the more recent empirical literature on belief flexibility as applied to delusions. The methodology and evidence in relation to studies of belief flexibility and the Bias Against Disconfirmatory Evidence (BADE) across the delusional continuum will be critically appraised, and implications drawn for improving cognitive therapy. It will be proposed that dual process models of reasoning, which Kahneman (Kahneman, 2011) popularised as 'fast and slow thinking', provide a useful theoretical framework for integrating further research and informing clinical practice. The emergence of therapies which specifically target fast and slow thinking in people with distressing delusions will be described.

Examining reasoning biases in schizophrenia using a modified "Jumping to Conclusions" probabilistic reasoning task

Although the Jumping To Conclusion (JTC) bias has been extensively studied in relation to schizophrenia and persecutory delusions, the relationship between JTC and other reasoning biases implicated in delusional ideation is not fully understood. We modified the traditional JTC task to assess co-occurrence of reasoning biases in decision making. Forty-six patients with schizophrenia and 46 healthy controls completed two versions [neutral colored beads and salient comments] of the modified task. We replicated previous findings indicating that patients showed a greater JTC bias, and in both groups, the JTC bias was more pronounced for the salient task. However, we observed a significant effect for non-Bayesian judgments, indicating that patients showed greater difficulty in probabilistic reasoning. When controlling for probabilistic reasoning ability, the observed JTC bias effects were diminished. Our findings that faulty probability assessment accounts for the JTC bias indicates that the traditional JTC bias task may not represent an inherent hasty decision-making bias, but rather an inability to fully understand and execute the stated goals of the task. These results call into question the current understanding of the JTC bias and the independence of this bias apart from the cognitive demands of the task.

The relationship between anomalistic belief and biases of evidence integration and jumping to conclusions

Biases in the assessment and integration of evidence are likely contributors to anomalistic (e.g., paranormal, extra-terrestrial) beliefs because of the non-evidence based nature of these beliefs. However, little research has examined the relationship between anomalistic beliefs and evidence integration biases. The current study addressed this gap by examining the relationship between anomalistic belief and four such biases; bias against disconfirmatory evidence (BADE), bias against confirmatory evidence (BACE), liberal acceptance bias, and the jumping to conclusions bias (JTC). Standard BADE scenarios were used to measure BADE, BACE, and the liberal acceptance bias: Participants were given three pieces of evidence, one at a time, and required to rate several alternative explanations. The JTC was measured using two draws-to-decisions tasks (beads and emotionally salient), and participants also completed measures of anomalistic belief and delusion-proneness. Results showed that liberal acceptance was the only evidence integration bias that significantly predicted greater overall anomalistic belief. However, this relationship was no longer significant once delusion proneness was controlled for. Additionally, BADE significantly predicted experiential (but not other types of) anomalistic beliefs even after controlling for delusion proneness. We propose that liberal acceptance may lead people to form anomalistic beliefs on the basis of little evidence, and that stronger BADE may make these beliefs highly resistant to change.

Are Psychotic Experiences Related to Poorer Reflective Reasoning?

Background: Cognitive biases play an important role in the formation and maintenance of delusions. These biases are indicators of a weak reflective mind, or reduced engaging in reflective and deliberate reasoning. In three experiments, we tested whether a bias to accept non-sense statements as profound, treat metaphorical statements as literal, and suppress intuitive responses is related to psychotic-like experiences.

Methods: We tested deliberate reasoning and psychotic-like experiences in the general population and in patients with a former psychotic episode. Deliberate reasoning was assessed with the bullshit receptivity scale, the ontological confabulation scale and the cognitive reflection test (CRT). We also measured algorithmic performance with the Berlin numeracy test and the wordsum test. Psychotic-like experiences were measured with the Community Assessment of Psychic Experience (CAPE-42) scale.

Results: Psychotic-like experiences were positively correlated with a larger receptivity toward bullshit, more ontological confabulations, and also a lower score on the CRT but not with algorithmic task performance. In the patient group higher psychotic-like experiences significantly correlated with higher bullshit receptivity.

Conclusion: Reduced deliberate reasoning may contribute to the formation of delusions, and be a general thinking bias largely independent of a person's general intelligence. Acceptance of bullshit may be facilitated the more positive symptoms a patient has, contributing to the maintenance of the delusions.

Delusional Themes Across Affective and Non-Affective Psychoses

The current debate about the diagnostic significance of delusion revolves around two positions. The neurocognitive position conceives delusion as a non-specific, though polymorphic, symptom. The psychopathological position views features of delusion such as content and structure as having meaningful connections with diagnostic entities. This study aims at contributing to this debate by examining the association between delusional themes and diagnosis in a sample of 830 adult psychotic patients. All diagnoses were made by experienced psychiatrists according to DSM-IV or ICD-10 criteria, and in 348 patients were established with the SCID-I. All patients were administered the Brief Psychiatric Rating Scale (BPRS). In each patient, the presence of somatic delusions and delusions of guilt, grandiosity, and persecution was determined by examining the scores on relevant BPRS items. Delusions of guilt were almost pathognomonic for a psychotic depressive condition (psychotic major depression 40%; psychotic bipolar depression 30%; depressed schizoaffective disorder 8%; bipolar and schizoaffective mixed states 6 and 7%, respectively). Only 1% of patients with schizophrenia and no patient with delusional disorder or bipolar or schizoaffective manic state showed such delusions. The difference between unipolar and bipolar depression and the other diagnostic groups was highly significant. Delusions of grandiosity characterized mostly patients with manic symptoms (bipolar mania 20%; bipolar mixed states 19%; manic schizoaffective disorder 10%). They were observed significantly more often in bipolar mania than in schizophrenia (7%). Persecutory delusions were broadly distributed across diagnostic categories. However, they were significantly more frequent among patients with schizophrenia and delusional disorder compared with depressed and manic patients. Somatic delusions were also observed in all diagnostic groups, with no group standing out as distinct from the others in terms of an increased prevalence of somatic delusions. Our findings suggest a middle position in the debate between the neurocognitive and the psychopathological approaches. On the one hand, the widespread observation of persecutory delusions suggests the usefulness of searching for non-specific pathogenic mechanisms. On the other hand, the association between some delusional contents and psychiatric diagnosis suggests that a phenomenological analysis of the delusional experience may be a helpful tool for the clinician in the diagnostic process.

SlowMo, a digital therapy targeting reasoning in paranoia, versus treatment as usual in the treatment of people who fear harm from others: study protocol for a randomised controlled trial

Background

Paranoia is one of the most common symptoms of schizophrenia-spectrum disorders, and is associated with significant distress and disruption to the person’s life. Developing more effective and accessible psychological interventions for paranoia is a clinical priority. Our research team has approached this challenge in two main ways: firstly, by adopting an interventionist causal approach to increase effectiveness and secondly, by incorporating user-centred inclusive design methods to enhance accessibility and usability. Our resultant new digital intervention, SlowMo, intensively targets a reasoning style associated with paranoia, fast thinking, characterised by jumping to conclusions and belief inflexibility. It consists of an easy-to-use, enjoyable and memorable digital interface. An interactive web-based app facilitates delivery of face-to-face meetings which is then synchronised with an innovative mobile app for use in daily life.

Methods/Design

We aim to test the clinical efficacy of SlowMo over 24 weeks to determine the mechanisms through which it reduces paranoia, and to identify participant characteristics that moderate its effectiveness. In a parallel-group randomised controlled trial, with 1:1 allocation, 360 participants with distressing persecutory beliefs will be independently randomised to receive either the SlowMo intervention added to treatment as usual (TAU) or TAU, using randomly varying permuted blocks, stratified by paranoia severity and site. Research workers will be blind to therapy allocation. The primary outcome is paranoia severity over 24 weeks; our hypothesised mechanism of change is reasoning; moderators include negative symptoms and working memory; and secondary outcomes include wellbeing, quality of life, and service use. The accessibility, usability and acceptability of the digital platform will be assessed.

Discussion

SlowMo has been developed as the first blended digital therapy to target fears of harm from others through an inclusive design approach. In addition to testing its efficacy, this trial will add to our understanding of psychological mechanisms in paranoia. The study will examine the usability and adherence of a novel digital therapy, including an app for self-management, in a large sample of people affected by severe mental health difficulties.

Trial registration

ISRCTN registry, ID: ISRCTN32448671. Registered prospectively on 30 January 2017. Date assigned 2 February 2017.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2242-7) contains supplementary material, which is available to authorized users.

Analytic cognitive style predicts paranormal explanations of anomalous experiences but not the experiences themselves: Implications for cognitive theories of delusions

BACKGROUND AND OBJECTIVES

It has been proposed that delusional beliefs are attempts to explain anomalous experiences. Why, then, do anomalous experiences induce delusions in some people but not in others? One possibility is that people with delusions have reasoning biases that result in them failing to reject implausible candidate explanations for anomalous experiences. We examine this hypothesis by studying paranormal interpretations of anomalous experiences.

METHODS

We examined whether analytic cognitive style (i.e. the willingness or disposition to critically evaluate outputs from intuitive processing and engage in effortful analytic processing) predicted anomalous experiences and paranormal explanations for these experiences after controlling for demographic variables and cognitive ability.

RESULTS

Analytic cognitive style predicted paranormal explanations for anomalous experiences, but not the anomalous experiences themselves.

LIMITATIONS

We did not study clinical delusions. Our attempts to control for cognitive ability may have been inadequate. Our sample was predominantly students.

CONCLUSIONS

Limited analytic cognitive style might contribute to the interpretation of anomalous experiences in terms of delusional beliefs.

A Bayesian perspective on delusions: Suggestions for modifying two reasoning tasks

BACKGROUND AND OBJECTIVES

There are a range of mechanistic explanations on the formation and maintenance of delusions. Within the Bayesian brain hypothesis, particularly within the framework of predictive coding models, delusions are seen as an aberrant inference process characterized by either a failure in sensory attenuation or an aberrant weighting of prior experience. Testing of these Bayesian decision theories requires measuring of both the patients' confidence in their beliefs and the confidence they assign new, incoming information. In the Bayesian framework we apply here, the former is referred to as the prior while the latter is usually called the data or likelihood.

METHODS AND RESULTS

This narrative review will commence by giving an introduction to the basic concept underlying the Bayesian decision theory approach to delusion. A consequence of crucial importance of this sketch is that it provides a measure for the persistence of a belief. Experimental tasks measuring these parameters are presented. Further, a modification of two standard reasoning tasks, the beads task and the evidence integration task, is proposed that permits testing the parameters from Bayesian decision theory.

LIMITATIONS

Patients differ from controls by the distress the delusions causes to them. The Bayesian Decision theory framework has no explicit parameter for distress.

CONCLUSIONS

A more detailed reporting of differences between patients with delusions is warranted.

The relationship between cognitive biases and psychological dimensions of delusions: The importance of jumping to conclusions

BACKGROUND AND OBJECTIVES

Cognitive biases play a role in the development and maintenance of delusions. However, delusions are multidimensional (i.e., emotional and cognitive facets) and often co-occur with auditory hallucinations. Therefore, further refinement of the precise relationship between cognitive biases, delusions, and hallucinatory experiences is warranted.

METHODS

A total sample of 167 patients with schizophrenia spectrum disorders was split into two groups consisting of patients with active delusions (n = 127) and active hallucinations (n = 92). All patients were assessed for delusions and hallucinations using the semi-structured psychotic symptom rating scales (PSYRATS), which assesses the emotional (i.e., distress) and cognitive (i.e., conviction, preoccupation) dimensions of these symptoms. Cognitive biases were assessed with the Cognitive Biases Questionnaire for Psychosis (CBQp) self-report questionnaire (assessing jumping to conclusions, intentionalising, catastrophising, emotional reasoning, and dichotomous thinking biases). Multiple stepwise regressions were performed to investigate the relationship between delusions and cognitive biases, while controlling for auditory hallucinations (and vice-versa).

RESULTS

The only cognitive bias to significantly predict delusions after controlling for the severity of auditory hallucinations was the jumping to conclusions (JTC) bias (predicted both emotional and cognitive dimensions). Only the emotional dimension of auditory hallucinations was predicted by the intentionalising and dichotomous thinking biases, after delusional severity was controlled for.

LIMITATIONS

The cross-sectional design precludes causal inferences. Only positive psychotic symptoms were assessed and no wider psychopathology assessment was utilised (e.g., negative symptoms, anxiety, depression).

CONCLUSIONS

The jumping to conclusions bias is associated with both delusional conviction and emotional distress.

Beads task vs. box task: The specificity of the jumping to conclusions bias

BACKGROUND AND OBJECTIVES

Previous research involving the probabilistic reasoning 'beads task' has consistently demonstrated a jumping-to-conclusions (JTC) bias, where individuals with delusions make decisions based on limited evidence. However, recent studies have suggested that miscomprehension may be confounding the beads task. The current study aimed to test the conventional beads task against a conceptually simpler probabilistic reasoning "box task" METHODS: One hundred non-clinical participants completed both the beads task and the box task, and the Peters et al. Delusions Inventory (PDI) to assess for delusion-proneness. The number of 'draws to decision' was assessed for both tasks. Additionally, the total amount of on-screen evidence was manipulated for the box task, and two new box task measures were assessed (i.e., 'proportion of evidence requested' and 'deviation from optimal solution').

RESULTS

Despite being conceptually similar, the two tasks did not correlate, and participants requested significantly less information on the beads task relative to the box task. High-delusion-prone participants did not demonstrate hastier decisions on either task; in fact, for box task, this group was observed to be significantly more conservative than low-delusion-prone group.

LIMITATIONS

Neither task was incentivized; results need replication with a clinical sample.

CONCLUSION

Participants, and particularly those identified as high-delusion-prone, displayed a more conservative style of responding on the novel box task, relative to the beads task. The two tasks, whilst conceptually similar, appear to be tapping different cognitive processes. The implications of these results are discussed in relation to the JTC bias and the theoretical mechanisms thought to underlie it.

A two-stage cognitive theory of the positive symptoms of psychosis. Highlighting the role of lowered decision thresholds

OBJECTIVES

We outline a two-stage heuristic account for the pathogenesis of the positive symptoms of psychosis.

METHODS

A narrative review on the empirical evidence of the liberal acceptance (LA) account of positive symptoms is presented.

HYPOTHESIS

At the heart of our theory is the idea that psychosis is characterized by a lowered decision threshold, which results in the premature acceptance of hypotheses that a nonpsychotic individual would reject. Once the hypothesis is judged as valid, counterevidence is not sought anymore due to a bias against disconfirmatory evidence as well as confirmation biases, consolidating the false hypothesis. As a result of LA, confidence in errors is enhanced relative to controls. Subjective probabilities are initially low for hypotheses in individuals with delusions, and delusional ideas at stage 1 (belief formation) are often fragile. In the course of the second stage (belief maintenance), fleeting delusional ideas evolve into fixed false beliefs, particularly if the delusional idea is congruent with the emotional state and provides "meaning". LA may also contribute to hallucinations through a misattribution of (partially) normal sensory phenomena. Interventions such as metacognitive training that aim to "plant the seeds of doubt" decrease positive symptoms by encouraging individuals to seek more information and to attenuate confidence. The effect of antipsychotic medication is explained by its doubt-inducing properties.

LIMITATIONS

The model needs to be confirmed by longitudinal designs that allow an examination of causal relationships. Evidence is currently weak for hallucinations.

CONCLUSIONS

The theory may account for positive symptoms in a subgroup of patients. Future directions are outlined.

Holding on to false beliefs: The bias against disconfirmatory evidence over the course of psychosis

BACKGROUND AND OBJECTIVES

The ability to integrate evidence into a reasoning process is crucial in order to react to changing information, e.g. to adapt one's beliefs according to new evidence or to generate new beliefs when facing better alternatives. Evidence integration ability is thus associated with belief flexibility. A specific bias of evidence integration, a bias against disconfirmatory evidence (BADE), can be found in patients with schizophrenia and has been linked to delusion development and maintenance. Knowledge about whether the BADE occurs already in risk constellations of psychosis can clarify its role in the pathogenesis of psychosis.

METHODS

This article reviews the current literature on BADE. Many studies demonstrate BADE over the course of illness, ranging from healthy controls with subclinical properties of schizotypy, over patients with at-risk mental states (ARMS) and patients with a first episode of psychosis to patients with chronic schizophrenia. These data allow a comparison of competences and deficits over the course of illness. Underlying mechanisms of BADE are discussed, including interrelations with neurocognitive performance and dopaminergic processes.

RESULTS

The BADE could be found in different phases of psychosis development and can be regarded as a cognitive marker of the beginning psychotic state.

LIMITATIONS

The presented findings are derived from independent cross-sectional studies. So far, no comprehensive longitudinal assessment has been published.

CONCLUSIONS

Treatments of metacognitive deficits in general and as early as in the ARMS might interfere with the cognitive pathogenesis of psychosis, and thereby ameliorate, postpone or even prevent the transition to psychosis.

Transdiagnostic Extension of Delusions: Schizophrenia and Beyond

Delusion is central to the conceptualization, definition, and identification of schizophrenia. However, in current classifications, the presence of delusions is neither necessary nor sufficient for the diagnosis of schizophrenia, nor is it sufficient to exclude the diagnosis of some other psychiatric conditions. Partly as a consequence of these classification rules, it is possible for delusions to exist transdiagnostically. In this article, we evaluate the extent to which this happens, and in what ways the characteristics of delusions vary according to diagnostic context. We were able to examine their presence and form in delusional disorder, affective disorder, obsessive-compulsive disorder, borderline personality disorder, and dementia, in all of which they have an appreciable presence. There is some evidence that the mechanisms of delusion formation are, at least to an extent, shared across these disorders. This transdiagnostic extension of delusions is an argument for targeting them therapeutically in their own right. However there is a dearth of research to enable the rational transdiagnostic deployment of either pharmacological or psychological treatments.