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

Evaluation of a brief online multi-index assessment for predicting increased psychotic-like experiences in the community: A perceptual, cognitive and affective approach

Research has shown that impairments in perception, reasoning, and social cognition are evident across the psychosis continuum and are implicated in the transition from subclinical symptoms to clinical psychosis. In this pilot feasibility study, a brief computerised assessment of visual perception, reasoning, social cognition and emotion dysregulation was administered to 157 adults in the community alongside self-report measures of psychotic-like experiences. The feasibility, reliability, and the predictive validity of the assessment tool were examined. The assessment procedure was feasible, evidenced through high completion rates. However, reliability estimates were suboptimal for online assessment measures. Self-reported visual perception and state emotion dysregulation predicted psychotic-like experiences explaining 53% of the variance when controlling for age. This study provides preliminary evidence that state difficulties with emotion regulation and self-reported visual perception abnormalities can predict increased psychotic-like experiences in the community. Future adaptations could address technological issues encountered with assessment tasks and ensure measures are psychometrically robust when administered online. Brief online assessments hold potential for research of both cognition and affect along the psychosis continuum although caution must be exercised with the chosen methodology.

Two decades of metacognitive training for psychosis: successes, setbacks, and innovations

INTRODUCTION

Schizophrenia is among the most debilitating mental health conditions. While antipsychotic medication represents the primary pillar of treatment, guidelines now also recommend psychotherapy. Metacognitive Training (MCT) has emerged over the past 20 years as a novel approach that addresses the cognitive biases involved in the pathogenesis of schizophrenia. MCT seeks to enhance patients' awareness of their cognitive distortions and reduce overconfidence. MCT is available in individual and group formats.

AREAS COVERED

This review provides a comprehensive overview of MCT, detailing its theoretical foundations, development, and implementation. The authors present meta-analyses demonstrating its efficacy in improving positive symptoms as well as negative symptoms and self-esteem. Lastly, the review covers the integration of the COGITO app to support MCT. For our narrative review we searched data bases including PubMed, Web of Science, EMBASE, PsycINFO, and MEDLINE.

EXPERT OPINION

MCT represents a significant advance in the treatment of schizophrenia, offering a flexible, low-threshold intervention that can be easily implemented in various clinical settings. The training's focus on metacognitive processes provides patients with tools to understand and manage their symptoms. Future research should seek to develop shortened as well as more personalized versions and investigate the long-term sustainability of the effects.

Psychotic-Like Reasoning Styles in Patients With Borderline Personality Disorder? An Experimental Investigation of the Jumping to Conclusions Bias

INTRODUCTION

Patients with borderline personality disorder (BPD) commonly display psychotic symptoms such as hallucinations or delusional/paranoid ideas. We used the fish task to investigate cognitive biases (jumping to conclusions and overcorrection) implicated in the aetiology of psychotic symptoms in patients with BPD.

METHODS

Participants received consecutive pieces of information to determine which of two lakes a fisherman was catching fish from. Outcome measures were draws to decision and frequency of premature decisions after just one and after not more than two fish (jumping to conclusions), probability estimate at the time of the decision (decision threshold) and adjustment of the probability estimate after receiving disconfirmatory information (overcorrection). With data aggregated from multiple studies, a total of 170 patients with BPD and 72 healthy controls (parallelized by age, gender and education) participated.

RESULTS

The two groups showed similar draws to decision and frequencies of premature decisions. The decision threshold was also comparable across the groups. However, the patients with BPD showed overcorrection.

CONCLUSIONS

The experimental study found no evidence for a jumping to conclusions bias or a lower decision threshold in patients with BPD. The stronger adjustment of probability estimates (overcorrection) in patients with BPD is compatible with the unstable affect, self-image and interpersonal relationships observed in patients with BPD.

Investigating the associations between personality functioning, cognitive biases, and (non-)perceptive clinical high-risk symptoms of psychosis in the community

BACKGROUND

Beyond psychosis prediction, clinical high-risk (CHR-P) symptoms show clinical relevance by their association with functional impairments and psychopathology, including personality pathology. Impaired personality functioning is prioritized in recent dimensional personality disorder models (DSM-5, ICD-11), yet underexplored in CHR-P, as are associations with cognitive biases, which early studies indicate as possibly linking CHR-P-symptoms and personality pathology.

METHODS

A community sample (N = 444, 17-60 years, 61.8% female) was assessed via clinical telephone interview and online questionnaires. Using zero-inflated Poisson models, we explored associations of personality functioning, cognitive biases, current psychopathology, and psychosocial functioning with likelihood and severity of overall CHR-P, as well as perceptive (per-) and non-perceptive (nonper-)CHR-P-symptoms distinctly.

RESULTS

Higher nonper-CHR-P-symptom likelihood was associated with more impaired personality functioning and psychosocial functioning, while more severe cognitive biases were associated with higher CHR-P- and per-CHR-P-symptom likelihood, alongside higher CHR-P- and nonper-CHR-P-symptom severity. Further, more axis-I diagnoses were linked to higher CHR-P-, per-CHR-P-, and nonper-CHR-P-symptom likelihood, and younger age to higher CHR-P- and per-CHR-P-symptom severity, with CHR-P-symptom severity appearing higher in females. In an exploratory analysis, personality functioning elements identity and self-direction, and cognitive biases dichotomous thinking, emotional reasoning, and catastrophizing, respectively, showed multifaceted associations with nonper-CHR-P-symptom likelihood and overall CHR-P-symptom expression.

CONCLUSIONS

Our study supports the association of CHR-P-symptoms with multiple mental health factors. Findings suggest intricate associations between personality functioning impairments and cognitive biases with CHR-P-symptom expression in non-help-seeking populations, possibly contributing to different per-CHR-P- and nonper-CHR-P-symptom expression patterns. Therefore, they should be targeted in future longitudinal studies, aiming at better understanding CHR-P-manifestations to inform preventive intervention.

Bridging perspectives - A review and synthesis of 53 theoretical models of delusions

The degree to which numerous existing models of delusion formation disagree or propose common mechanisms remains unclear. To achieve a comprehensive understanding of delusion aetiology, we summarised 53 theoretical models of delusions extracted from a systematic literature search. We identified central aspects and unique or overarching features of five core perspectives: cognitive (n = 22), associative learning (n = 4), social (n = 6), neurobiological (n = 6), and Bayesian inference (n = 15). These perspectives differ in foci and mechanistic explanations. Whereas some postulate delusions to result from associative and operant learning, others assume a disbalance in the integration of prior beliefs and sensory input or emphasise the relevance of information processing biases. Postulated moderators range from maladaptive generalised beliefs over neurocognitive impairment to dopamine, stress, and affective dysregulation. The models also differ in whether they attempt to explain delusion formation in general or the delusional content (i.e., persecutory). Finally, some models postulate functional aspects of delusions, such as insight relief. Despite their differences, the perspectives converge on the idea that delusions form as an explanation for an experienced ambiguity. Building on this common ground, we propose an integrative framework incorporating essential mechanistic explanations from each perspective and discuss its implications for research and clinical practice.

On the relationship between subjective decision criteria and paranoid ideations

Following the conjecture made by (Bliznashki and Hristova in Appetite 167:105645, 2021), we test the hypothesis that liberal subjective decision criteria exhibited during a task involving discrimination between random and systematically correlated patterns should be associated with elevated levels of paranoid ideations. Study 1 establishes the proposed association in the presence of several control measures while also demonstrating that the relationship in question is significantly moderated by subjects' working memory spans and tendencies to be overconfident in their judgments. Study 2 provides further evidence that these effects are indeed specific to tasks involving discrimination between random and systematic patterns and that the observed results are not due to some form of (anti) acquiescence bias or other general trends. Certain specifics of the correlation matrices involving cognitive measures significantly related to the paranoia continuum suggest that our results are consistent with the Entropic Brain Hypothesis. Finally, a simulation study employing a Neural Network demonstrates that increased entropy and liberal decision criteria might be connected to each other with said connection being amenable to an interpretation within the Bayesian paradigm.

Individual differences in belief updating and phasic arousal are related to psychosis proneness

Many decisions entail the updating of beliefs about the state of the environment by accumulating noisy sensory evidence. This form of probabilistic reasoning may go awry in psychosis. Computational theory shows that optimal belief updating in environments subject to hidden changes in their state requires a dynamic modulation of the evidence accumulation process. Recent empirical findings implicate transient responses of pupil-linked central arousal systems to individual evidence samples in this modulation. Here, we analyzed behavior and pupil responses during evidence accumulation in a changing environment in a community sample of human participants. We also assessed their subclinical psychotic experiences (psychosis proneness). Participants most prone to psychosis showed overall less flexible belief updating profiles, with diminished behavioral impact of evidence samples occurring late during decision formation. These same individuals also exhibited overall smaller pupil responses and less reliable pupil encoding of computational variables governing the dynamic belief updating. Our findings provide insights into the cognitive and physiological bases of psychosis proneness and open paths to unraveling the pathophysiology of psychotic disorders.

The contributions of risk-taking and impulsivity to jumping to conclusions in the psychosis spectrum

The jumping to conclusions (JTC) bias has been linked to the formation and maintenance of delusions across the psychosis spectrum. However, it remains unclear whether this bias reflects a primary cognitive deviation or is secondary to other cognitive processes. To this end, we investigated the relationship between JTC, risk-taking, impulsivity, and sensation seeking in individuals with psychotic-like experiences (PLEs) and controls. A large online community sample (N = 1151) completed the Fish Task as a measure for the JTC bias, as well as the Balloon Analogue Risk Task (BART) and the Brief Risk-Taking Propensity Scale (R-1) as measures of the propensity to take risks. Measures assessing impulsivity (Impulsive Behavior Scale-8, I-8), sensation seeking (Brief Sensation Seeking Scale, BSSS-4), and verbal intelligence (12-item Wordsum test) were also administered. We dichotomized the sample into extreme groups based on the positive subscale of the Community Assessment of Psychotic Experiences (CAPE). The present study confirms the existence of a JTC bias in psychosis-prone individuals. Of note, PLE-high individuals self-reported higher risk-taking propensity in the R-1 while at the same time displaying higher objective risk aversion in the BART relative to controls, speaking for a dissociation of subjective versus objective risk-taking behavior. PLE-high individuals showed deviances in other psychological traits (impulsivity, sensation seeking), but these were not associated with hasty decision-making as measured by JTC or risk-taking propensity. The results speak against impulsivity, sensation seeking, or verbal intelligence as driving mechanisms of JTC and risky decision-making.

Hallucination-Proneness is Associated With a Decrease in Robust Averaging of Perceptual Evidence

BACKGROUND AND HYPOTHESIS

Hallucinations are characterized by disturbances in perceptual decision-making about environmental stimuli. When integrating across multiple stimuli to form a perceptual decision, typical observers engage in "robust averaging" by down-weighting extreme perceptual evidence, akin to a statistician excluding outlying data. Furthermore, observers adapt to contexts with more unreliable evidence by increasing this down-weighting strategy. Here, we test the hypothesis that hallucination-prone individuals (n = 38 high vs n = 91 low) would show a decrease in this robust averaging and diminished sensitivity to changes in evidence variance.

STUDY DESIGN

We used a multielement perceptual averaging task to elicit dichotomous judgments about the "average color" (red/blue) of an array of stimuli in trials with varied strength (mean) and reliability (variance) of decision-relevant perceptual evidence. We fitted computational models to task behavior, with a focus on a log-posterior-ratio (LPR) model which integrates evidence as a function of the log odds of each perceptual option and produces a robust averaging effect.

STUDY RESULTS

Hallucination-prone individuals demonstrated less robust averaging, seeming to weigh inlying and outlying extreme or untrustworthy evidence more equally. Furthermore, the model that integrated evidence as a function of the LPR of the two perceptual options and produced robust averaging showed poorer fit for the group prone to hallucinations. Finally, the weighting strategy in hallucination-prone individuals remained insensitive to evidence variance.

CONCLUSIONS

Our findings provide empirical support for theoretical proposals regarding evidence integration aberrations in psychosis and alterations in the perceptual systems that track statistical regularities in environmental stimuli.

What Kurt Schneider Really Said and What the DSM Has Made of it in Its Different Editions: A Plea to Redefine Hallucinations in Schizophrenia

Kurt Schneider has played a leading role in shaping our current view of schizophrenia, placing certain manifestations of delusions and hallucinations at the center of the disorder, especially ideas of persecution and voice-hearing. The first part of this review summarizes Schneider's original ideas and then traces how the different editions of the DSM merged aspects of Kraepelin's, Bleuler's, and Schneider's historical concepts. Special attention is given to the transition from the DSM-IV to the DSM-5, which eliminated much of Schneider's original concept. In the second part of the article, we contrast the current definition of hallucination in the DSM-5 with that of Schneider. We present empirically derived arguments that favor a redefinition of hallucinations, much in accordance with Schneider's original ideas. We plea for a two-dimensional model of hallucinations that represents the degree of insight and perceptuality, ranging from thoughts with full "mineness" via perception-laden thoughts and intrusions (including "as if" experiences") to hallucinations. While we concur with the DSM-5 that cognitions that are indistinguishable from perceptions should be labeled as hallucinations, we suggest expanding the definition to internally generated sensory phenomena, including those with only partial resemblance to external perceptions, that the individual considers real and that may lie at the heart of a subsequent delusional superstructure.

Metacognitive training in the acute psychiatric care setting: feasibility, acceptability, and safety

Patients on acute psychiatric wards desire more psychosocial treatment than they receive, according to recent studies, but evidence-based interventions tailored to this setting are currently lacking. Metacognitive Training for psychosis (MCT) is a flexible, easy-to-administer group therapy that has been adapted to meet this demand (MCT-Acute). Thirty-seven patients with severe mental illness took part in MCT-Acute twice a week during their stay on a locked acute ward and were interviewed before, during, and after the intervention period regarding subjective utility, subjective adverse events, and symptom severity; attendance rates and reasons for absence were recorded. In addition, staff rated adverse events, symptom severity, and functioning (German Clinical Trial Register ID: DRKS00020551). Overall, most patients evaluated MCT-Acute positively and reported symptom stabilization. Staff also reported improvement in functioning. No clinician-rated adverse events related to participation in MCT-Acute were reported. Conducting MCT-Acute is feasible and safe and may contribute to meeting patients', practitioners', and researchers' demands for more evidence-based psychotherapeutic interventions for the acute psychiatric care setting.

Clinical Trial Registration

ID: DRKS00020551, https://drks.de/search/de/trial/DRKS00020551.

Hasty decision making and belief inflexibility in the more delusion prone? A modified disambiguating-scenarios paradigm assessing cognitive biases implicated in delusions

INTRODUCTION

Contemporary models of psychosis imply that cognitive biases such as the jumping to conclusions (JTC), the bias against disconfirmatory evidence (BADE), and the liberal acceptance (LA) bias play a role in the pathogenesis of delusions. Most of the studies investigating the role of cognitive biases, however, have been conducted with socially neutral or abstract stimuli and have assessed patients with established psychoses. For the present study, we aimed to concurrently investigate multiple biases (i.e., the JTC, BADE, and LA biases) in a community sample with a new paradigm using more socially engaging stimuli.

METHODS

A large sample of participants (N = 874) recruited via Amazon Mechanical Turk was subdivided into two groups based on the frequency of their psychotic-like experiences (PLEs) according to the positive subscale score of the Community Assessment of Psychic Experiences (CAPE) and matched based on major demographics variables, resulting in two equally sized groups called High-PLE (at least 2 SD above the mean) and Low-PLE (maximum 0.5 above the mean; n = 46 for each group). Using a modified version of the written-scenarios BADE task, which emphasized social interactions between agents embedded in the scenario, participants rated the plausibility of response options in the face of new information.

RESULTS

In line with previous findings, the High-PLE group demonstrated the JTC, BADE, and LA biases. That is, the members of this group made more decisions after the initial piece of information, were less likely to revise their beliefs in light of new information, and provided higher plausibility ratings for implausible response options compared to the Low-PLE group.

CONCLUSIONS

Results corroborate prior findings suggesting that the JTC, BADE, and LA biases may be contributing factors in delusional ideation and that metacognitive biases extend to social situations.

Reasoning biases and delusional ideation in the general population: A longitudinal study

BACKGROUND

Reasoning biases have been suggested as risk factors for delusional ideation in both patients and non-clinical individuals. Still, it is unclear how these biases are longitudinally related to delusions in the general population. We hence aimed to investigate longitudinal associations between reasoning biases and delusional ideation in the general population.

METHODS

We conducted an online cohort study with 1184 adults from the German and Swiss general population. Participants completed measures on reasoning biases (jumping-to-conclusion bias [JTC], liberal acceptance bias [LA], bias against disconfirmatory evidence [BADE], possibility of being mistaken [PM]) and delusional ideation at baseline, and delusional ideation 7 to 8 months later.

RESULTS

A greater JTC bias was associated with a greater increase in delusional ideation over the following months. This association was better described by a positive quadratic relationship. Neither BADE, LA nor PM were associated with subsequent changes in delusional ideation.

CONCLUSIONS

This study suggests that jumping-to-conclusions predicts delusional ideation in the general population but that this association may follow a quadratic trajectory. While no other associations turned significant, future studies with shorter temporal distances may shed further light on the role of reasoning biases as risk factors for delusional ideation in non-clinical samples.

Associations between acceptance of the implausible bias, theory of mind and delusions in first-episode psychosis patients; A longitudinal study

Multiple different cognitive biases, among them the liberal acceptance (LA) bias, have been suggested to contribute to reality distortion in psychotic disorders. Earlier studies have been cross-sectional and considered a limited set of cognitive correlates of psychosis, thus the relationship between LA bias and psychosis remains poorly known. We studied a similar bias (acceptance of the implausible (AOI)) in 62 first-episode psychosis (FEP) patients and 62 control subjects, who watched movie scenes with varying degrees of realism and were asked to evaluate the probability of these events occurring in real life. We assessed theory of mind (ToM) performance using the Hinting task and delusion severity using Brief Psychiatric Rating Scale item 11. We correlated the magnitude of AOI with the severity of delusions and performance in the ToM task. Furthermore, we used 1-year follow-up data from 40 FEP patients and 40 control subjects to disentangle state vs trait-like characteristics of AOI. At baseline FEP patients expressed more AOI than control subjects, and the magnitude of AOI correlated positively with the severity of delusions and negatively with ToM performance. At the one-year follow-up, when most patients were in remission, patients still displayed increased AOI, which no longer correlated with delusions. These findings support the notion that the AOI bias could represent a trait rather than a state feature and support further studies to test the hypothesis that it could be one of the causal factors of psychotic disorders, possibly associated with ToM.

Development of the French version of the Davos Assessment of Cognitive Biases Scale in a non-clinical sample of young adults

BACKGROUND

In accordance with continuum and cognitive behaviour models of psychosis, cognitive biases precede the onset and the maintenance of positive symptoms. The Davos Assessment of Cognitive Biases Scale (DACOBS), a self-report measure, was developed to explore the prevalence of specific cognitive biases. This study aims to validate the French version of this instrument.

METHODS

We first translated the English version of the DACOBS into French. Then, using a sample of 213 French speaking young adults (mean age = 20.54, SD = 1.65; 83% females), we examined the factor structure, internal consistency, concurrent, and convergent validities of the current version.

RESULTS

We found an 18-item, four-factor version of the French DACOBS comprising external attribution bias (five items), social cognition problems (five items), subjective cognition problems (five items), and safety behaviours (five items), provided best fit-to-data. Internal consistency for the resulting subscales ranged from acceptable to excellent (Cronbach's α range = .62-.86). All subscales were significantly, positively associated with a measure of psychotic-like experiences and positively associated with established measures of theoretically relevant constructs, demonstrating concurrent and convergent validity of the French DACOBS.

CONCLUSIONS

The French DACOBS is a reliable and valid and reliable instrument assessing cognitive biases, in a French-speaking youth population. Ultimately, the French DACOBS may be used to identify at-risk youth which may benefit from cognitive interventions targeting cognitive biases, safety behaviours and social cognition which could potentially prevent transition to psychosis in youth.

A pilot 1-year follow-up randomised controlled trial comparing metacognitive training to psychoeducation in schizophrenia: effects on insight

Poor insight in schizophrenia spectrum disorders (SSD) is linked with negative outcomes. This single-centre, assessor-blind, parallel-group 1-year follow-up randomised controlled trial (RCT) tested whether metacognitive training (MCT) (compared to psychoeducation) may improve insight and outcomes in outpatients with SSD assessed: at baseline (T0); after treatment (T1) and at 1-year follow-up (T2). Insight (primary outcome) was measured with (i) the Schedule for Assessment of Insight-Expanded version- (SAI-E), including illness recognition (IR), symptom relabelling (SR), treatment compliance (TC) and total insight scores (TIS); and (ii) the Beck Cognitive Insight Scale (BCIS). Between-group comparisons were nonsignificant, while within the MCT group (but not within controls) there was a significant medium effect size for improved TIS at T2 (d = 0.67, P = 0.02). Secondary outcomes included cognitive measures: Jumping to Conclusions (JTC), Theory of Mind (ToM), plus symptom severity and functioning. Compared to psychoeducation, MCT improved the PANSS excitement (d = 1.21, P = 0.01) and depressed (d = 0.76, P = 0.05) factors at T2; and a JTC task both at T1 (P = 0.016) and at T2 (P = 0.031). Participants in this RCT receiving MCT showed improved insight at 1-year follow-up, which was associated with better mood and reduced JTC cognitive bias. In this pilot study, no significant benefits on insight of MCT over psychoeducation were detected, which may have been due to insufficient power.

State-like changes in the salience network correlate with delusion severity in first-episode psychosis patients

BACKGROUND AND HYPOTHESIS

Delusions are characteristic of psychotic disorders; however, the brain correlates of delusions remain poorly known. Imaging studies on delusions typically compare images across individuals. Related confounding of inter-individual differences beyond delusions may be avoided by comparing delusional and non-delusional states within individuals.

STUDY DESIGN

We studied correlations of delusions using intra-subject correlation (intra-SC) and inter-subject correlation of functional magnetic resonance imaging (fMRI) signal time series, obtained during a movie stimulus at baseline and follow-up. We included 27 control subjects and 24 first-episode psychosis patients, who were free of delusions at follow-up, to calculate intra-SC between fMRI signals obtained during the two time points. In addition, we studied changes in functional connectivity at baseline and during the one-year follow-up using regions where delusion severity correlated with intra-SC as seeds.

RESULTS

The intra-SC correlated negatively with the baseline delusion severity in the bilateral anterior insula. In addition, we observed a subthreshold cluster in the anterior cingulate. These three regions constitute the cortical salience network (SN). Functional connectivity between the bilateral insula and the precuneus was weaker in the patients at baseline than in patients at follow-up or in control subjects at any time point.

CONCLUSIONS

The results suggest that intra-SC is a powerful tool to study brain correlates of symptoms and highlight the role of the SN and internetwork dysconnectivity between the SN and the default mode network in delusions.

Metacognitive Training to Improve Insight and Work Outcome in Schizophrenia

ABSTRACT

Individuals with psychotic disorders have deficits in metacognition. Thirty-four adults with schizophrenia were randomized to 2 months of metacognitive training (MCT) or a healthy living skills control group. All participants were enrolled in a work therapy program, followed by a supported employment program. Assessments were conducted at baseline, at the end of the 2-month active intervention, and at 4- and 12-month follow-ups. At the end of active intervention, the MCT group demonstrated greater improvement and better work behavior relative to controls. At follow-up, the MCT group demonstrated significantly greater insight and fewer positive symptoms and a greater percentage were employed in the community. We speculate that being better able to think about one's thoughts, recognize biases in thinking, and correct those thoughts may aid in responding to workplace challenges and hence improve work outcomes.

Functional brain networks underlying probabilistic reasoning and delusions in schizophrenia

Delusions in schizophrenia are false beliefs that are assigned certainty and not afforded the scrutiny that normally gives rise to doubt, even under conditions of weak evidence. The goal of the current functional magnetic resonance imaging (fMRI) study is to identify the brain network(s) involved in gathering information under conditions of weak evidence, in people with schizophrenia experiencing delusions. fMRI activity during probabilistic reasoning in people with schizophrenia experiencing delusions (n = 29) compared to people with schizophrenia not experiencing delusions (n = 41) and healthy controls (n = 41) was observed when participants made judgments based on evidence that weakly or strongly matched (or mismatched) with the focal hypothesis. A brain network involved in visual attention was strongly elicited for conditions of weak evidence for healthy controls and patients not experiencing delusions, but this increase was absent for patients experiencing delusions. This suggests that the state associated with delusions manifests in fMRI as reduced activity in an early visual attentional process whereby weak evidence is incorrectly stamped as conclusive, manifestating as a feeling of fluency and misplaced certainty, short-circuiting the search for evidence, and providing a candidate neural process for 'seeding' delusions.

Premature commitment to uncertain decisions during human NMDA receptor hypofunction

Making accurate decisions based on unreliable sensory evidence requires cognitive inference. Dysfunction of n-methyl-d-aspartate (NMDA) receptors impairs the integration of noisy input in theoretical models of neural circuits, but whether and how this synaptic alteration impairs human inference and confidence during uncertain decisions remains unknown. Here we use placebo-controlled infusions of ketamine to characterize the causal effect of human NMDA receptor hypofunction on cognitive inference and its neural correlates. At the behavioral level, ketamine triggers inference errors and elevated decision uncertainty. At the neural level, ketamine is associated with imbalanced coding of evidence and premature response preparation in electroencephalographic (EEG) activity. Through computational modeling of inference and confidence, we propose that this specific pattern of behavioral and neural impairments reflects an early commitment to inaccurate decisions, which aims at resolving the abnormal uncertainty generated by NMDA receptor hypofunction.

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.

Confident memory errors and disrupted reality testing in early psychosis

Schizophrenia is a psychiatric disorder characterized by a disruption in reality testing most often manifest in the form of delusions and hallucinations. Because determining the reality-basis of prior experiences is dependent on episodic and associative memory, deficits in mnemonic processes could be involved in the genesis of impaired reality testing. In the present study, we used an associative memory paradigm incorporating confidence ratings to examine whether patients with a recent onset of schizophrenia (n = 48) show a greater propensity for confident, yet incorrect responses during retrieval testing than healthy controls (n = 26) and whether such confident incorrect responses, specifically, are more strongly associated with positive symptoms than with negative symptoms. Using an analysis of variance design, we found that first-episode schizophrenia patients made a significantly greater number of confident errors than controls (i.e. they expressed high confidence in having seen pairs of items that were not paired at encoding and high confidence in having not seen pairs of items that were paired at encoding). We also found that the number of confident errors was specifically and differentially associated with positive symptom severity, to a significantly greater degree than with negative symptom severity and psychosocial functioning, and this association was not found between positive symptoms and uncertain responses, nor positive symptoms and overall task performance. These findings suggest that the propensity for incorrect memory judgements with high confidence, specifically, may be uniquely associated with disrupted reality testing and that this type of cognitive impairment is distinct from general deficits in memory and cognition in this respect.

Do you like cliff-hangers? Objective versus subjective need for closure in the schizophrenia spectrum

Need for closure (NFC) is a cognitive bias that has been implicated in the pathogenesis of delusions. A general population sample (N = 1465) was dichotomized into high versus low schizotypal participants and matched based on core social demographic characteristics (each n = 98). For the first time, we aimed at capturing NFC subjectively (with the NFC Scale) and objectively with a new experimental paradigm, the Ambiguous Movie Scene Task. In this task, participants viewed video scenes with either open or closed endings (i.e., high or low ambiguity) and rated their (emotional) reactions to the clips. Open endings were expected to lead to more frustration (i.e., due to increased need for closure) and to induce greater eagerness to learn about the possible resolution among those high on positive schizotypy. High schizotypal individuals displayed higher scores on the NFC Scale than low schizotypal individuals. Contrary to our expectations, high schizotypal participants did not recognize video scenes with open endings as ambiguous and were less eager to learn about a possible resolution than low schizotypal individuals. In the Ambiguous Movie Scene Task, high schizotypal individuals showed evidence of a jumping to conclusions bias rather than frustration over unresolved storylines. We found an overall stronger emotional response in schizotypal participants and overconfidence in their judgments. The NFC Scale and selected scores of the new task correlated moderately. The study corroborates earlier evidence for a dissociation between objective and subjective biases in the psychosis spectrum.

Hallucinations and Delusions as Low-Quality Attributions: Influencing Factors and Proposal for Their Analysis

Hallucinations and delusions, in keeping with the distress accompanying them, are major features in the diagnosis of psychosis in international classifications. In spite of their human and clinical importance, the concepts are unclear. The distinction between hallucinations and delusions in terms of perception-thought is not precise enough, causing problems in analyzing the patient's words. Nor are the differentiations or variations within each precise enough. Continuing the long clinical tradition discussing the distinction between hallucinations and delusions while assuming their similarities, this study poses a concept integrating the two phenomena as attributions people make about themselves and their settings. Then the elements of any attribution can be used as guides for structuring significant literature on both, and reduce analytical ambiguity. Such attributions make more sense within the structure of two-way relationships with factors in a person's own framework and setting. This structure is described with its variables and relationships as a guide to assessment, follow-up, and intervention. Two checklists are provided for orientation.

Delusion progression process from the perspective of patients with psychoses: A descriptive study based on the primary delusion concept of Karl Jaspers

BACKGROUND

Delusion occupies an important position in the diagnosis and treatment of patients with psychoses. Although Karl Jaspers' concept of the primary delusion (PD) is a key hypothesis in descriptive phenomenology concerning the primordial experience of delusion, to our knowledge it has not been verified in empirical studies of patients with psychosis, and the relationship between PDs and fully developed delusions remains unclear.

METHODS

The subjects were 108 psychiatric patients diagnosed with DSM-IV schizophrenia or schizoaffective disorder who had persisting delusions. This investigation used a newly devised semi-structured interview, the Delusion and its Origin Assessment Interview (DOAI), and the Positive and Negative Syndrome Scale. PDs enquired about in the DOAI were delusional perception, delusional memory, delusional mood, and delusional intuition. Associations of PDs with delusion themes and delusion features extracted from DOAI items by factor analysis were examined using correlational and MANCOVA regression analyses. Reliability studies of the DOAI were also conducted.

RESULTS

The reliability and correlation analyses suggested robust psychometric properties of the DOAI. The percentages of subjects reporting PD phenomena as delusion origins and currently present were 93% and 84%, respectively. MANCOVA revealed several significant associations, including between delusional perception and delusional mood and persecutory themes, between delusional intuition and grandiose delusions, and between delusional perception and intuition and systematization of delusions.

DISCUSSION

This study demonstrates that PDs can be considered as principal origins of delusions by subjects with psychosis, and have meaningful connections with the characteristics of their fully developed delusions. The associations between PDs and delusion characteristics can be interpreted in terms of progression processes of delusions, which are seen as intensification and generalization of cognitive and affective pathologies in PDs. The findings are also consistent with the neurobiological hypothesis that aberrant salience attribution to stimuli, as in PDs, is the primary phenomenon caused by abnormal dopamine system regulation. Further studies are needed to clarify delusion progression processes relating to PDs and to substantiate their clinical meanings.

Delusions beyond beliefs: a critical overview of diagnostic, aetiological, and therapeutic schizophrenia research from a clinical-phenomenological perspective

Delusions are commonly conceived as false beliefs that are held with certainty and which cannot be corrected. This conception of delusion has been influential throughout the history of psychiatry and continues to inform how delusions are approached in clinical practice and in contemporary schizophrenia research. It is reflected in the full psychosis continuum model, guides psychological and neurocognitive accounts of the formation and maintenance of delusions, and it substantially determines how delusions are approached in cognitive-behavioural treatment. In this Review, we draw on a clinical-phenomenological framework to offer an alternative account of delusion that incorporates the experiential dimension of delusion, emphasising how specific alterations to self-consciousness and reality experience underlie delusions that are considered characteristic of schizophrenia. Against that backdrop, we critically reconsider the current research areas, highlighting empirical and conceptual issues in contemporary delusion research, which appear to largely derive from an insufficient consideration of the experiential dimension of delusions. Finally, we suggest how the alternative phenomenological approach towards delusion could offer new ways to advance current research and clinical practice.

Schizotypy is associated with difficulty maintaining multiple hypotheses

Among neurocognitive accounts of delusions, there is a growing consensus that it is the certainty with which delusions are held, rather than their content that defines some beliefs as delusional. On a continuum model of psychosis, this inappropriate certainty ought to be present (albeit in an attenuated form) in healthy adults who score highly in schizotypy. It was hypothesised that this might be most evident in circumstances where the environment provides incomplete or probabilistic information, which thereby forces the participant to hold two imperfectly supported, concurrent hypotheses in mind. A cued visual search task was used to measure people's capacity to use partially predictive information (i.e., a cue that predicted the target may occur in one of the two locations) to facilitate speeded responding. As hypothesised, people's performance on the trials that required holding two hypotheses in mind concurrently was significantly and specifically associated with the positive components of schizotypy. This finding is consistent with a hyperfocusing of attention in schizophrenia, and may help explain why delusion-prone individuals have a tendency to "jump to conclusions" or be resistant to disconfirming information when faced with multiple, partially supported hypotheses.

Confidence in visual motion discrimination is preserved in individuals with schizophrenia

BACKGROUND

Metacognition is the set of reflexive processes that allows humans to evaluate the accuracy of their mental operations. Metacognitive deficits have been described in people with schizophrenia using mostly narrative assessment, and they have been linked to several key symptoms.

METHODS

We assessed metacognitive performance objectively by asking people with schizophrenia or schizoaffective disorder (n = 20) and matched healthy participants (n = 21) to perform a visual discrimination task and report their confidence in their performance. Metacognitive performance was defined as the adequacy between visual discrimination performance and confidence.

RESULTS

Bayesian analyses revealed equivalent metacognitive performance in the 2 groups, despite a weaker association between confidence and trajectory tracking during task execution among people with schizophrenia. We reproduced these results using an evidence accumulation model, which showed similar decisional processes in the 2 groups.

LIMITATIONS

These results from a relatively small study sample cannot be generalized to other perceptual and nonperceptual tasks. To meet this purpose, ecological tasks are needed. As well, the role of antipsychotic medication and design deserves greater attention in the future.

CONCLUSION

We found similar decisional and metacognitive capabilities between people with schizophrenia and healthy controls in a visual discrimination task.

The Strasbourg Visual Scale: A Novel Method to Assess Visual Hallucinations

The experience of oneself in the world is based on sensory afferences, enabling us to reach a first-perspective perception of our environment and to differentiate oneself from the world. Visual hallucinations may arise from a difficulty in differentiating one's own mental imagery from externally-induced perceptions. To specify the relationship between hallucinations and the disorders of the self, we need to understand the mechanisms of hallucinations. However, visual hallucinations are often under reported in individuals with psychosis, who sometimes appear to experience difficulties describing them. We developed the "Strasbourg Visual Scale (SVS)," a novel computerized tool that allows us to explore and capture the subjective experience of visual hallucinations by circumventing the difficulties associated with verbal descriptions. This scale reconstructs the hallucinated image of the participants by presenting distinct physical properties of visual information, step-by-step to help them communicate their internal experience. The strategy that underlies the SVS is to present a sequence of images to the participants whose choice at each step provides a feedback toward re-creating the internal image held by them. The SVS displays simple images on a computer screen that provide choices for the participants. Each step focuses on one physical property of an image, and the successive choices made by the participants help them to progressively build an image close to his/her hallucination, similar to the tools commonly used to generate facial composites. The SVS was constructed based on our knowledge of the visual pathways leading to an integrated perception of our environment. We discuss the rationale for the successive steps of the scale, and to which extent it could complement existing scales.

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.

The role of expectancies and emotional load in false auditory perceptions among patients with schizophrenia spectrum disorders

Cognitive models suggest that top-down and emotional processes increase false perceptions in schizophrenia spectrum disorders (SSD). However, little is still known about the interaction of these processes in false auditory perceptions. The present study aimed at investigating the specific as well as joint impacts of expectancies and emotional load on false auditory perceptions in SSD. Thirty-three patients with SSD and 33 matched healthy controls were assessed with a false perception task. Participants were asked to detect a target stimulus (a word) in a white noise background (the word was present in 60% of the cases and absent in 40%). Conditions varied in terms of the level of expectancy (1. no cue prior to the stimulus, 2. semantic priming, 3. semantic priming accompanied by a video of a man's mouth spelling out the word). The words used were neutral or emotionally negative. Symptom severity was assessed with the Positive and Negative Syndrome Scale. Higher expectancy significantly increased the likelihood of false auditory perceptions only among the patients with SSD (the group x expectancy condition interaction was significant), which was unrelated to general cognitive performance. Emotional load had no impact on false auditory perceptions in either group. Patients made more false auditory perceptions with high confidence than controls did. False auditory perceptions were significantly correlated with the severity of positive symptoms and disorganization, but not with other dimensions. Perception in SSD seems to be susceptible to top-down processes, increasing the likelihood of high-confidence false auditory perceptions.

Psychosis and Psychotic-Like Symptoms Affect Cognitive Abilities but Not Motivation in a Foraging Task

Background and Objective

Goal-directed behavior is a central feature of human functioning. It requires goal appraisal and implicit cost-benefit analyses, i.e., how much effort to invest in the pursuit of a certain goal, against its value and a confidence judgment regarding the chance of attainment. Persons with severe mental illness such as psychosis often struggle with reaching goals. Cognitive deficits, positive symptoms restricting balanced judgment, and negative symptoms such as anhedonia and avolition may compromise goal attainment. The objective of this study was to investigate to what degree symptom severity is related to cognitive abilities, metacognition, and effort-based decision-making in a visual search task.

Methods

Two studies were conducted: study 1: N = 52 (healthy controls), and study 2: N = 46 (23 patients with psychosis/23 matched healthy controls). Symptoms were measured by the CAPE-42 (study 1) and the PANSS (study 2). By using a visual search task, we concomitantly measured (a) accuracy in short-term memory, (b) perceived accuracy by participants making a capture area or confidence interval, and (c) effort by measuring how long one searched for the target. Perseverance was assessed in trials in which the target was omitted and search had to be abandoned.

Results

Higher levels of positive symptoms, and having a diagnosis of psychosis, were associated with larger errors in memory. Participants adjusted both their capture area and their search investment to the error of their memory. Perseverance was associated with negative symptoms in study 1 but not in study 2.

Conclusion

By simultaneously assessing error and confidence in one's memory, as well as effort in search, we found that memory was affected by positive, not negative, symptoms in healthy controls, and was reduced in patients with psychosis. However, impaired memory did not concur with overconfidence or less effort in search, i.e., goal directed behavior was unrelated to symptoms or diagnosis. Metacognition and motivation were neither affected by cognitive abilities nor by negative symptoms. Clinically, this could indicate that struggles with goal directed behavior in psychosis may not solely be dependent on primary illness factors.

Moderators of treatment efficacy in individualized metacognitive training for psychosis (MCT+)

BACKGROUND AND OBJECTIVES

Individualized Metacognitive Training (MCT+) is a manualized intervention designed to improve delusional severity by reducing delusion-associated cognitive biases such as jumping-to-conclusions. Increased interest in personalized medicine stipulates the identification of patients who are more likely to benefit from specialized interventions. The present study aimed to explore baseline moderators of MCT+ efficacy on delusions and overall positive symptoms in psychosis.

METHODS

We analyzed data from a randomized rater-blind controlled trial, in which 92 patients with psychotic disorders and current or past delusions were randomly assigned to either MCT+ or CogPack®, a cognitive remediation software. Baseline moderator variables consisted of jumping-to-conclusions, cognitive insight, quality of life, self-esteem, selective attention, and patients' attitudes towards their symptoms. Linear mixed-effects models were applied to investigate specific moderators of MCT+ efficacy.

RESULTS

In MCT+ relative to CogPack, presence of a jumping-to-conclusions bias, a lowered decision threshold, and low self-esteem were associated with larger improvements in delusional severity and/or overall positive symptoms over time. Subjective reasoning style and insight, as well as subjective attitudes towards psychosis, did not moderate the treatment efficacy of MCT+ relative to CogPack.

LIMITATIONS

Participation of both treatment groups in group MCT as a part of standard care, possibly leading to additional effects on delusional severity.

CONCLUSIONS

Patients with low self-esteem and those who are prone to jumping-to-conclusions seem to particularly benefit from MCT+. Our results can help inform clinical practice as they provide specific criteria for selecting patients for whom MCT+ is most appropriate.

Jumping to conclusions in the less-delusion-prone? Preliminary evidence from a more reliable beads task

BACKGROUND AND OBJECTIVES

Several meta-analyses have shown that people with psychosis tend to gather less information (i.e., they make fewer draws to decision, or DTD) on the beads task than healthy controls. A single meta-analysis has also found a small negative association between delusion-proneness and DTD in healthy samples, but with considerable heterogeneity.

METHODS

We used the new and more reliable "distractor sequences" beads task to clarify the nature of the relationship between delusion-proneness and DTD in a healthy sample. Healthy participants (N = 203) completed the distractor sequences beads task and the Peters Delusions Inventory (PDI), which measures delusion-proneness.

RESULTS

PDI and DTD were positively correlated, and those who jumped to conclusions (DTD ≤ 2) had lower PDI than those who did not. Comparing PDI quartiles on DTD provided some evidence the positive association did not extend to the highest PDI quartile. We found that DTD and delusion-proneness were positively related in our non-clinical sample, which was unexpected.

LIMITATIONS

Results need replication with a clinical sample.

CONCLUSIONS

Considering the well-established association between the JTC bias and clinical delusions, the current finding may reflect a relationship that differs between non-clinical and clinically significant delusional groups, or one which reverses sign at some level of delusion-proneness.

Effort and liberal acceptance bias in patients with schizophrenia

Introduction: A liberal acceptance bias is implicated in the formation and maintenance of delusions in schizophrenia. The present study tested the hypothesis that patients with schizophrenia are more quickly satisfied with their task performance than controls despite poor objective performance. Methods: Fifty patients with schizophrenia and 50 healthy controls performed the newly developed copy figure task in which participants copy a complex geometrical figure up to eight times until they are satisfied with the result. Objective performance was scored blind to group status. Subjective performance was rated on a 10-point scale. Carefulness of the drawing using anchor points served as a proxy for effort. Results: Patients made as many attempts as controls to copy the figure despite their worse subjective and objective performance. The number of attempts was negatively correlated with (persecutory) delusions and the PANSS total score. Neither effort nor possible frustration due to a plateau in performance was a reason for task termination. Conclusions: This exploratory study is in line with predictions based on the liberal acceptance model. For future studies, we recommend further cross-validating this paradigm and testing whether patients' retrospective assessment of their performance is exaggerated relative to controls. We also suggest that researchers pursue this line of research with personally meaningful material where a decreased threshold of acceptance may more easily translate into the subsequent fixation of ideas.

Prolonged rather than hasty decision-making in schizophrenia using the box task. Must we rethink the jumping to conclusions account of paranoia?

Jumping to conclusions (JTC) is the best established cognitive bias in schizophrenia and is increasingly targeted in interventions aimed to improve positive symptoms. To address shortcomings of the standard measure to capture JTC, the beads task, we developed a new variant-the box task-which was subsequently validated in people with elevated psychotic-like experiences. For the first time, the box task was administered in a sample of individuals with manifest schizophrenia. We hypothesized that patients with schizophrenia would display an elevated JTC bias relative to controls.

METHOD

We recruited a large sample of 101 patients with schizophrenia and matched them to an online sample recruited from the general population. In the box task, participants must decide which of two kinds of colored balls are presented more often. Participants are told that the task may end prematurely, and that task performance will be counted as an error if no decision had been made before that point. The primary measure was the number of draws to decision (DTD), where fewer DTD corresponds to greater JTC.

RESULTS

In contrast to expectations, participants with schizophrenia showed significantly higher DTD (i.e., reduced JTC). Consistent with our previous findings, patients also displayed a lowered decision threshold compared to controls. Response confidence for the final decision was lower in patients and correlated with self-esteem and positive symptoms. While there was evidence that previous knowledge of the box task lowered DTD, exclusion of participants with experience on the box task did not substantially change results.

DISCUSSION

The study fits a growing body of experiments casting doubt on the generalizability of the JTC effect in schizophrenia across different tasks. While the study tentatively supports a liberal acceptance account of psychosis, caution is warranted and we recommend that research should explore and control for potentially important mediators (e.g., task difficulty, stress, test-taking attitudes).

Cognitive biases in individuals with psychotic-like experiences: A systematic review and a meta-analysis

A prior meta-analyze using behavioral tasks demonstrated that individuals with subclinical delusional ideations jump to conclusion (JTC). The major aim of our systematic review and meta-analyses was to highlight the relationship between cognitive biases and psychotic-like experiences (PLEs) when both are assessed by self-reports measures. In accordance with PRISMA guidelines, four electronic databases were searched. A total of 669 studies were identified, 39 articles met inclusion criteria for the systematic review and 27 for the random effects meta-analysis on healthy and UHR samples investigating cognitive biases (JTC, aberrant salience (ASB), attention to threat (ATB), externalizing bias (ETB), belief inflexibility (BIB), personalizing bias, aggression bias and need for closure). Effect size estimates were calculated using Pearson's correlation coefficients (r). In samples including both healthy and Ultra High Risk (UHR) individuals, positive psychotic-like experiences (PPLEs) were positively associated with ATB (rs = 0.38), ETB (rs = 0.35), BIB (rs = 0.19), JTC (rs = 0.10), and personalizing (rs = 0.24). In community samples, PPLEs were positively associated with ASB (rs = 0.62), ATB (rs = 0.34), ETB (rs = 0.36), BIB (rs = 0.18), JTC (rs = 0.11). In addition, negative PLEs were positively associated with ATB (rs = 0.28), ETB (rs = 0.37), BIB (rs = 0.19) and ASB (rs = 0.18). In UHR samples, positive associations were established between PPLEs and ATB (rs = 0.47), ETB (rs = 0.34), personalizing (rs = 0.36) and the aggression bias (rs = 0.35). Our results support cognitive models of psychosis considering the role of cognitive biases in the onset and the maintenance of psychotic symptoms. Cognitive interventions targeting cognitive biases could potentially prevent transition to psychosis in youth reporting PLEs and in UHR.

Jumping to conclusions in the less-delusion-prone? Further evidence from a more reliable beads task

BACKGROUND

A single meta-analysis has found that healthy people with higher delusion-proneness tend to gather less information (i.e., make fewer draws to decision, or DTD) on the beads task, although the findings of contributing studies were mixed, and the pooled effect size was small. However, using a new and more reliable "distractor sequences" beads task, we recently found a positive relationship between delusion-proneness and DTD in a healthy sample. In the current study, we re-tested this relationship in a new sample, and tested the possibility that the relationship is driven by participant's ability to understand and use odds or likelihood information ("odds literacy").

METHODS

Healthy participants (N = 167) completed the distractor sequences beads task, the Peters Delusions Inventory (PDI) which measures delusion-proneness, a measure of odds literacy, and the Depression, Anxiety, and Stress scale.

RESULTS

PDI and DTD were positively correlated, and comparing PDI quartiles on DTD confirmed a statistically significant trend of increasing DTD with PDI quartile. Odds literacy was positively rather than negatively associated with both DTD and PDI. Anxiety was positively correlated with PDI and DTD.

CONCLUSIONS

We replicated our earlier finding that DTD and delusion-proneness were positively related in a non-clinical sample, but found that increased odds-literacy did not drive lower PDI and DTD, and hence did not explain their covariance. It is possible however that anxiety and co-occurring risk aversion drive increased delusion-proneness and information-gathering, potentially accounting for the positive relationship between PDI and DTD.

The Role of Personal Identity on Positive and Negative Symptoms in Psychosis: A Study Using the Repertory Grid Technique

BACKGROUND

People with psychosis experience disruptions in personal identity that affect positive and negative symptoms, but the complexity of these phenomena needs to be addressed in an in-depth manner. Using the Personal Construct Theory, we examined whether distinct dimensions of personal identity, as measured with the Repertory Grid Technique along with other cognitive factors, might influence psychotic symptomatology.

METHOD

Eighty-five outpatients with schizophrenia-spectrum disorders completed a repertory grid, an observed-rated interview of psychotic symptoms, and measures of cognitive insight, depressive symptoms, neurocognition, and theory of mind.

RESULTS

Structural equation models revealed that interpersonal dichotomous thinking directly affected positive symptoms. Self-discrepancies influenced positive symptoms by mediation of depressive symptoms. Interpersonal cognitive differentiation and interpersonal cognitive richness mediated the impact of self-reflectivity and neurocognitive deficits in negative symptomatology.

CONCLUSIONS

This study is the first of its kind to examine the structure of personal identity in relation to positive and negative symptoms of psychosis. Results suggest interventions targeted to improving interpersonal dichotomous thinking, self-discrepancies, interpersonal cognitive differentiation, and interpersonal cognitive richness may be useful in improving psychotic symptoms.

Advice weighting as a novel measure for belief flexibility in people with psychotic-like experiences

Jumping to conclusions and bias against disconfirmatory evidence are two cognitive biases common in people with psychotic-like experiences and psychosis. However, many participants show comprehension problems doing traditional tasks; new paradigms with additional applied scenarios are thus needed. A large MTurk community sample (N = 1422) was recruited and subdivided into participants with high levels of psychotic-like experiences (at least 2 SD above the mean, n = 79) and participants with low levels of psychotic-like experiences (maximum 0.5 SD above the mean, n = 1110), based on the positive subscale of the Community Assessment of Psychic Experiences (CAPE). In the context of a judge-advisor system, participants made an initial estimate and then received advice that was either confirmatory or disconfirmatory. Participants then gave a new, possibly revised estimate and were allowed to seek additional advice. Participants with high levels of psychotic-like experiences gave their final assessment after receiving significantly less advice and were significantly more confident in their decision than participants with low psychotic-like experiences, in line with previous studies on jumping to conclusions and overconfidence. Contrary to the hypothesis and earlier studies, however, no deficit in belief revision was found. In fact, participants with high psychotic-like experiences weighted advice significantly higher in the condition with disconfirmatory advice, but only for the first advice they received. The increased weighting of a single piece of disconfirmatory advice can be explained by the hypersalience of evidence-hypothesis matches theory, according to which more weight is attached to the most recently available information.

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.

Abnormalities of confidence in psychiatry: an overview and future perspectives

Our behavior is constantly accompanied by a sense of confidence and its' precision is critical for adequate adaptation and survival. Importantly, abnormal confidence judgments that do not reflect reality may play a crucial role in pathological decision-making typically seen in psychiatric disorders. In this review, we propose abnormalities of confidence as a new model of interpreting psychiatric symptoms. We hypothesize a dysfunction of confidence at the root of psychiatric symptoms either expressed subclinically in the general population or clinically in the patient population. Our review reveals a robust association between confidence abnormalities and psychiatric symptomatology. Confidence abnormalities are present in subclinical/prodromal phases of psychiatric disorders, show a positive relationship with symptom severity, and appear to normalize after recovery. In the reviewed literature, the strongest evidence was found for a decline in confidence in (sub)clinical OCD, and for a decrease in confidence discrimination in (sub)clinical schizophrenia. We found suggestive evidence for increased/decreased confidence in addiction and depression/anxiety, respectively. Confidence abnormalities may help to understand underlying psychopathological substrates across disorders, and should thus be considered transdiagnostically. This review provides clear evidence for confidence abnormalities in different psychiatric disorders, identifies current knowledge gaps and supplies suggestions for future avenues. As such, it may guide future translational research into the underlying processes governing these abnormalities, as well as future interventions to restore them.

Does uncertainty breed conviction? On the possible role of compensatory conviction in jumping to conclusions and overconfidence in psychosis

Background: Jumping to conclusions (JTC) and overconfidence in errors are well established in individuals with a liability to psychosis. Experimental research suggests that subjecting individuals to dilemmas and doubt prompts a subsequent hardening of attitudes and may foster delusion-like convictions. For the present study, we examined whether this compensatory conviction process is exaggerated in individuals with a liability to psychosis and might in part explain JTC and overconfidence. Methods: A large sample of participants from the general population were screened for psychotic experiences with the Community Assessment of Psychic Experiences scale (CAPE) and then randomly allocated to either a condition in which they should experience doubt or a control condition. Participants (final sample, n = 650) were then tested on JTC and overconfidence. Results: Participants who scored high on the positive subscale of the CAPE made fewer draws to decision, showed greater confidence, and made more errors relative to low scorers. Yet, none of the parameters was modulated by experimental condition. Conclusions: Our results at present do not support the idea that JTC is elevated by a prior experience of a dilemma or doubt. Yet, this possibility should not be entirely dismissed as the presumed process may take time to evolve and perhaps needs to be more pervasive.

Liberal Acceptance Bias, Momentary Aberrant Salience, and Psychosis: An Experimental Experience Sampling Study

Cognitive models of psychosis posit that reasoning biases are an important mechanism contributing to the formation of psychotic symptoms, in part through transforming anomalous experiences of aberrant salience into frank psychotic symptoms. This study aimed to investigate the interplay of liberal acceptance (LA) bias, which is a specific type of reasoning bias, and momentary aberrant salience in the development of paranoid and psychotic experiences in daily life in first-episode psychosis patients (FEP), at-risk mental state participants (ARMS), and controls. We used a novel experimental Experience Sampling Methodology (eESM) task for measuring LA bias (ie, decisions based on low probability estimates) and ESM measures of momentary aberrant salience and paranoid and psychotic experiences in 51 FEP, 46 ARMS, and 53 controls. We found evidence that LA bias was more likely to occur in FEP than in controls. Further, LA bias was associated with psychotic and paranoid experiences (all P < .007) and modified the association between momentary aberrant salience and psychotic experiences (χ2(df) = 7.4(2), P = .025) in ARMS, such that momentary salience was associated with more intense psychotic experiences in the presence of LA bias in ARMS, but not in FEP and controls. Our findings suggest that LA bias may be central for anomalous experiences such as momentary aberrant salience to increase intensity of psychotic experiences in at-risk individuals. Further, LA bias appears to be more likely to be present, but not directly linked to current intensity of psychotic experiences, in treated FEP. Novel eESM tasks open new avenues for targeting psychological processes under real-world conditions.

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.

Investigation of sex differences in delusion-associated cognitive biases

In the past few decades, sex differences have been identified in a number of clinical, cognitive and functional outcomes in patients with schizophrenia spectrum disorders. However, to date, sex differences in higher-order cognitive biases have not been systematically studied. The present study aimed to examine sex differences in jumping-to-conclusions and evidence integration impairment based on data collected in two previous studies in patients with schizophrenia spectrum disorders and healthy controls. For this purpose, data from n = 58 patients and n = 60 healthy controls on the Fish Task (as a measure of jumping to conclusions) and bias against disconfirmatory evidence (BADE; as a measure of evidence integration) task were analyzed. Results indicated a lack of sex differences in jumping-to-conclusions and evidence integration impairment both in patients with schizophrenia spectrum disorders and healthy controls. Although the present study was adequately powered to detect sex differences of a low medium effect size, larger studies are warranted to exclude differences of a smaller magnitude between men and women regarding delusion-associated cognitive biases.

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.