Psychosis, Delusions and the "Jumping to Conclusions" Reasoning Bias: A Systematic Review and Meta-analysis

The relationship between early symptom severity, improvement and remission in first episode psychosis with jumping to conclusions

It is suggested that Jumping To Conclusions (JTC) reasoning bias might contribute to the distortion of external reality. However, the association between psychotic manifestations and JTC is obscure, especially if general intelligence is considered as a mediator. The aim of this study is to investigate the relation between severity, early clinical improvement and remission of symptoms in First Episode Psychosis (FEP) with JTC as an explanatory factor. One hundred seventy-one FEP individuals were evaluated with the Positive and Negative Syndrome Scale (PANSS) at baseline and one month after treatment initiation. Clinical improvement was ascribed as symptom change one-month post-baseline measurements. Symptomatic remission was assessed with the Andreasen severity criteria and JTC with the Beads Task, operationalized through Draws To Decision (DTD) (the lower the number of DTD, the higher the JTC bias). Regarding symptoms severity, total psychotic, total positive psychotic, and hallucinations-item PANSS scores showed a negative association with JTC after controlling for IQ. Regarding early clinical improvement, the association with JTC was non-significant. No significant association was detected between one month remission status of FEP and JTC. Our findings indicate that severity of positive symptoms is not associated with hastiness in decision-making, but rather with a heightened conservatism in terms of increased data gathering. Further research is required to replicate the results and clarify the cognitive processes involved.

Association Between Failures in Perceptual Updating and the Severity of Psychosis in Schizophrenia

IMPORTANCE

Recent accounts suggest that delusions and hallucinations may result from alterations in how prior knowledge is integrated with new information, but experimental evidence supporting this idea has been complex and inconsistent. Evidence from a simpler perceptual task would make clear whether psychotic symptoms are associated with overreliance on prior information and impaired updating.

OBJECTIVE

To investigate whether individuals with schizophrenia or schizoaffective disorder (PSZ) and healthy control individuals (HCs) differ in the ability to update their beliefs based on evidence in a relatively simple perceptual paradigm.

DESIGN, SETTING, AND PARTICIPANTS

This case-control study included individuals who met DSM-IV criteria for PSZ and matched HC participants in 2 independent samples. The PSZ group was recruited from the Maryland Psychiatric Research Center, Yale University, and community clinics, and the HC group was recruited from the community. To test perceptual updating, a random dot kinematogram paradigm was implemented in which dots moving coherently in a single direction were mixed with randomly moving dots. On 50% of trials, the direction of coherent motion changed by 90° midway through the trial. Participants were asked to report the direction perceived at the end of the trial. The Peters Delusions Inventory and Brief Psychiatric Rating Scale (BPRS) were used to quantify the severity of positive symptoms. Data were collected from September 2018 to March 2020 and were analyzed from approximately March 2020 to March 2021.

MAIN OUTCOMES AND MEASURES

Critical measures included the proportion of responses centered around the initial direction vs the subsequent changed direction and the overall precision of motion perception and reaction times.

RESULTS

A total of 48 participants were included in the PSZ group (31 [65%] male; mean [SD] age, 36.56 [9.76] years) and 36 in the HC group (22 [61%] male; mean [SD] age, 35.67 [10.74] years) in the original sample. An independent replication sample included 42 participants in the PSZ group (29 [69%] male; mean [SD] age, 33.98 [11.03] years) and 34 in the HC group (20 [59%] male; mean [SD] age, 34.29 [10.44] years). In line with previous research, patients with PSZ were less precise and had slower reaction times overall. The key finding was that patients with PSZ were significantly more likely (original sample: mean, 27.88 [95% CI, 24.19-31.57]; replication sample: mean, 26.70 [95% CI, 23.53-29.87]) than HC participants (original sample: mean, 18.86 [95% CI, 16.56-21.16]; replication sample: mean, 15.67 [95% CI, 12.61-18.73]) to report the initial motion direction rather than the final one. Moreover, the tendency to report the direction of initial motion correlated with the degree of conviction on the Peters Delusions Inventory (original sample: r = 0.32 [P = .05]; replication sample: r = 0.30 [P = .05]) and the Brief Psychiatric Rating Scale Reality Distortion score (original sample: r = 0.55 [P = .001]; replication sample: r = 0.35 [P = .03]) and severity of hallucinations (original sample: r = 0.39 [P = .02]; replication sample: r = 0.30 [P = .05]).

CONCLUSIONS AND RELEVANCE

The findings of this case-control study suggest that the severity of psychotic symptoms is associated with a tendency to overweight initial information over incoming sensory evidence. These results are consistent with predictive coding accounts of the origins of positive symptoms and suggest that deficits in very elementary perceptual updating may be a critical mechanism in psychosis.

People with jumping to conclusions bias tend to make context-independent decisions rather than context-dependent decisions

Beads task (BT) uses a probabilistic reasoning paradigm and reveals jumping to conclusions (JTC) bias, the tendency to make premature judgments based on insufficient information (i.e., making fewer draws to decision-DTD). In this study, healthy participants (N = 207) were tested on the 80:20 and 60:40 color ratio versions of BT. We investigated associations of JTC bias with a set of cognitive bias problems and Cognitive Bias Task (CBT), a non-veridical (agent-centered) decision-making task that determines context-dependent and context-independent decision-making bias.Results showed that the converted CBT scores were negatively, and cognitive bias scores were positively correlated with JTC bias (DTD ≤ 2) on both versions of the BT. The CBT demonstrated to have satisfactory convergent and predictive validity for JTC bias. The findings suggest that people with JTC bias fail to solve cognitive bias problems and are more likely to make context-independent response selections than context-dependent response selections.

Models of Dynamic Belief Updating in Psychosis-A Review Across Different Computational Approaches

To understand the dysfunctional mechanisms underlying maladaptive reasoning of psychosis, computational models of decision making have widely been applied over the past decade. Thereby, a particular focus has been on the degree to which beliefs are updated based on new evidence, expressed by the learning rate in computational models. Higher order beliefs about the stability of the environment can determine the attribution of meaningfulness to events that deviate from existing beliefs by interpreting these either as noise or as true systematic changes (volatility). Both, the inappropriate downplaying of important changes as noise (belief update too low) as well as the overly flexible adaptation to random events (belief update too high) were theoretically and empirically linked to symptoms of psychosis. Whereas models with fixed learning rates fail to adjust learning in reaction to dynamic changes, increasingly complex learning models have been adopted in samples with clinical and subclinical psychosis lately. These ranged from advanced reinforcement learning models, over fully Bayesian belief updating models to approximations of fully Bayesian models with hierarchical learning or change point detection algorithms. It remains difficult to draw comparisons across findings of learning alterations in psychosis modeled by different approaches e.g., the Hierarchical Gaussian Filter and change point detection. Therefore, this review aims to summarize and compare computational definitions and findings of dynamic belief updating without perceptual ambiguity in (sub)clinical psychosis across these different mathematical approaches. There was strong heterogeneity in tasks and samples. Overall, individuals with schizophrenia and delusion-proneness showed lower behavioral performance linked to failed differentiation between uninformative noise and environmental change. This was indicated by increased belief updating and an overestimation of volatility, which was associated with cognitive deficits. Correlational evidence for computational mechanisms and positive symptoms is still sparse and might diverge from the group finding of instable beliefs. Based on the reviewed studies, we highlight some aspects to be considered to advance the field with regard to task design, modeling approach, and inclusion of participants across the psychosis spectrum. Taken together, our review shows that computational psychiatry offers powerful tools to advance our mechanistic insights into the cognitive anatomy of psychotic experiences.

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.

Persons with first episode psychosis have distinct profiles of social cognition and metacognition

Subjects with first-episode psychosis experience substantial deficits in social cognition and metacognition. Although previous studies have investigated the role of profiles of individuals in social cognition and metacognition in chronic schizophrenia, profiling subjects with first-episode psychosis in both domains remains to be investigated. We used latent profile analysis to derive profiles of the abilities in 174 persons with first-episode psychosis using the Beck's Cognitive Insight Scale, the Faces Test, the Hinting Task, the Internal, Personal and Situational Attributions Questionnaire, and the Beads Task. Participants received a clinical assessment and a neuropsychological assessment. The best-fitting model was selected according to the Bayesian information criterion (BIC). We assessed the importance of the variables via a classification tree (CART). We derived three clusters with distinct profiles. The first profile (33.3%) comprised individuals with low social cognition. The second profile (60.9%) comprised individuals that had more proneness to present jumping to conclusions. The third profile (5.7%) presented a heterogeneous profile of metacognitive deficits. Persons with lower social cognition presented worse clinical and neuropsychological features than cluster 2 and cluster 3. Cluster 3 presented significantly worst functioning. Our results suggest that individuals with FEP present distinct profiles that concur with specific clinical, neuropsychological, and functional challenges. Each subgroup may benefit from different interventions.

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.

A cognitive model of delusion propensity through dysregulated correlation detection

BACKGROUND

We present a novel account of delusion propensity that integrates the roles of working memory (WM), decision criteria, and information gathering biases. This framework emphasises the role of aberrant correlation detection, which leads to the spurious perception of relationships between one's experiences. The frequency of such outcomes is moderated by the scaling of one's decision criteria which, for reasons discussed, must also account for WM capacity. The proposed dysregulated correlation detection account posits that propensity for delusional ideation is influenced by disturbances in this mechanism.

METHODS

Hypotheses were tested using a novel task that required participants (N = 92) to identify correlation between binary manipulations of simple shapes, presented as sequential pairs. Decision criteria and correlation detection were assessed under a Signal Detection Theory framework, while WM capacity was assessed through the Automated Operation Span Task and delusion propensity was measured using the Peters Delusion Inventory. Structural equation modeling was conducted to evaluate the proposed model.

RESULTS

Consistent with the central hypothesis, an interaction between decision criteria and WM was found to contribute significantly to delusion propensity through its effect on correlation detection accuracy. Greater delusion propensity was observed among participants with more liberal decision criteria, which was also in accordance with hypotheses. At the same time, the total effect of WM on delusion propensity was not found to be significant.

CONCLUSIONS

These findings provide preliminary support for the proposed dysregulated correlation detection account of propensity for delusional ideation.

You read my mind: fMRI markers of threatening appraisals in people with persistent psychotic experiences

Anomalous perceptual experiences are relatively common in the general population. Evidence indicates that the key to distinguishing individuals with persistent psychotic experiences (PEs) with a need for care from those without is how they appraise their anomalous experiences. Here, we aimed to characterise the neural circuits underlying threatening and non-threatening appraisals in people with and without a need for care for PEs, respectively. A total of 48 participants, consisting of patients with psychosis spectrum disorder (clinical group, n = 16), non-need-for-care participants with PEs (non-clinical group, n = 16), and no-PE healthy control participants (n = 16), underwent functional magnetic resonance imaging while completing the Telepath task, designed to induce an anomalous perceptual experience. Appraisals of the anomalous perceptual experiences were examined, as well as functional brain responses during this window, for significant group differences. We also examined whether activation co-varied with the subjective threat appraisals reported in-task by participants. The clinical group reported elevated subjective threat appraisals compared to both the non-clinical and no-PE control groups, with no differences between the two non-clinical groups. This pattern of results was accompanied by reduced activation in the superior and inferior frontal gyri in the clinical group as compared to the non-clinical and control groups. Precuneus activation scaled with threat appraisals reported in-task. Resilience in the context of persistent anomalous experiences may be explained by intact functioning of fronto-parietal regions, and may correspond to the ability to contextualise and flexibly evaluate psychotic experiences.

Dynamic Representation of the Subjective Value of Information

To improve future decisions, people should seek information based on the value of information (VOI), which depends on the current evidence and the reward structure of the upcoming decision. When additional evidence is supplied, people should update the VOI to adjust subsequent information seeking, but the neurocognitive mechanisms of this updating process remain unknown. We used a modified beads task to examine how the VOI is represented and updated in the human brain of both sexes. We theoretically derived, and empirically verified, a normative prediction that the VOI depends on decision evidence and is biased by reward asymmetry. Using fMRI, we found that the subjective VOI is represented in the right dorsolateral prefrontal cortex (DLPFC). Critically, this VOI representation was updated when additional evidence was supplied, showing that the DLPFC dynamically tracks the up-to-date VOI over time. These results provide new insights into how humans adaptively seek information in the service of decision-making.SIGNIFICANCE STATEMENT For adaptive decision-making, people should seek information based on what they currently know and the extent to which additional information could improve the decision outcome, formalized as the VOI. Doing so requires dynamic updating of VOI according to outcome values and newly arriving evidence. We formalize these principles using a normative model and show that information seeking in people adheres to them. Using fMRI, we show that the underlying subjective VOI is represented in the dorsolateral prefrontal cortex and, critically, that it is updated in real time according to newly arriving evidence. Our results reveal the computational and neural dynamics through which evidence and values are combined to inform constantly evolving information-seeking decisions.

Unstable Belief Formation and Slowed Decision-making: Evidence That the Jumping-to-Conclusions Bias in Schizophrenia Is Not Linked to Impulsive Decision-making

BACKGROUND

Jumping-to-conclusions (JTC) is a prominent reasoning bias in schizophrenia (SCZ). While it has been linked to not only psychopathological abnormalities (delusions and impulsive decision-making) but also unstable belief formation, its origin remains unclear. We here directly test to which extend JTC is associated with delusional ideation, impulsive decision-making, and unstable belief formation.

METHODS

In total, 45 SCZ patients were compared with matched samples of 45 patients with major depressive disorder (MDD) and 45 healthy controls (HC) as delusions and JTC also occur in other mental disorders and the general population. Participants performed a probabilistic beads task. To test the association of JTC with measures of delusions (Positive and Negative Syndrome Scale [PANSS]positive, PANSSpositive-factor, and Peter Delusions Inventory [PDI]), Bayesian linear regressions were computed. For the link between JTC and impulsive decision-making and unstable beliefs, we conducted between-group comparisons of "draws to decision" (DTD), "decision times" (DT), and "disconfirmatory evidence scores" (DES).

RESULTS

Bayesian regression obtained no robust relationship between PDI and DTD (all |R2adj| ≤ .057, all P ≥ .022, all Bayes Factors [BF01] ≤ 0.046; α adj = .00833). Compared with MDD and HC, patients with SCZ needed more time to decide (significantly higher DT in ambiguous trials: all P ≤ .005, r2 ≥ .216; numerically higher DT in other trials). Further, SCZ had unstable beliefs about the correct source jar whenever unexpected changes in bead sequences (disconfirmatory evidence) occurred (compared with MDD: all P ≤ .004 and all r2 ≥ .232; compared with HC: numerically higher DES). No significant correlation was observed between DT and DTD (all P ≥ .050).

CONCLUSIONS

Our findings point toward a relationship of JTC with unstable belief formation and do not support the assumption that JTC is associated with impulsive decision-making.

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.

Uncovering the realities of delusional experience in schizophrenia: a qualitative phenomenological study in Belgium

BACKGROUND

Delusions in schizophrenia are commonly approached as empirical false beliefs about everyday reality. Phenomenological accounts, by contrast, have suggested that delusions are more adequately understood as pertaining to a different kind of reality experience. How this alteration of reality experience should be characterised, which dimensions of experiential life are involved, and whether delusional reality might differ from standard reality in various ways is unclear and little is known about how patients with delusions value and relate to these experiential alterations. This study aimed to investigate the nature of delusional reality experience, and its subjective apprehension, in individuals with lived experience of delusions and a schizophrenia-spectrum diagnosis.

METHODS

In this qualitative phenomenological study, we recruited individuals with lived experience of delusions and a schizophrenia-spectrum diagnosis from two psychiatric-hospital services in Belgium using homogenous sampling. Criteria for participation were having undergone at least one psychotic episode with occurring delusional symptoms, present at least 1 year before participation, on the basis of clinical notes assessed by the attending psychiatrist; a schizophrenia-spectrum diagnosis, ascertained through clinical interview by the attending psychiatrist upon admission; being aged between 18 years and 65 years; and having the capacity to give informed consent. Exclusion criteria included worries concerning capacity to consent and risk of distress caused by participation. We did phenomenologically driven semi-structured interviews with the participants to explore the nature of delusional reality experience and their subjective valuation of these experiences. We used interpretative phenomenological analysis, a qualitative method tailored to the in-depth exploration of participants' first-person perspective, to analyse their accounts.

FINDINGS

Between March 2, 2020, and Sept 30, 2020, 18 adults (13 men and five women, aged 19-62 years) participated in the interview study. The findings suggest that delusions are often embedded in wide-ranging alterations of basic reality experience, involving quasi-ineffable atmospheric and ontological qualities that undermine participants' sense of the world as unambiguously real, fully present, and shared with others. We also found that delusional reality experience can differ from standard reality in various ways (ie, in a hypo-real and hyper-real form), across multiple dimensions (eg, meaningfulness, necessity and contingency, and detachment and engagement), and that participants are often implicitly or explicitly aware of the distinction between delusional and standard reality. Delusional experience can have an enduring value and meaning that is not fully captured by a strictly medical perspective.

INTERPRETATION

Increased awareness and recognition of the distinctive nature of delusional reality experience, in both clinical and research settings, can improve diagnostic accuracy, explanatory models, and therapeutic support for individuals with delusions whose lived realities are not always evident from an everyday perspective.

FUNDING

FWO Flanders.

TRANSLATION

For the Dutch translation of the abstract see Supplementary Materials section.

Functional outcomes and subjective recovery of jumping to conclusions in schizophrenia

This study investigated the effects of the bias known as jumping to conclusions (JTC) on objective functional outcomes as well as subjective assessments of quality of life (QoL) and personal recovery among a sample of patients diagnosed with schizophrenia. Specifically, this study assessed the variables of JTC, psychiatric symptoms, neurocognitive functioning, objective interpersonal and daily activities, vocational domains, subjective QoL, and personal recovery among 94 participants. Results showed that those in the JTC group had significantly lower neurocognitive and functional outcomes (moderate effect sizes); however, subjective measures such as QoL and personal recovery did not differ significantly according to JTC (small effect sizes). After adjusting for attributes, there were no statistically significant differences, but the JTC group demonstrated lower overall functional outcomes and higher individual recovery, each with a moderate effect size. This 'trade-off' is not evidence-guaranteed, and further research is recommended to examine the relationship between social functioning and personal recovery in people with JTC bias.

Effects of SlowMo, a Blended Digital Therapy Targeting Reasoning, on Paranoia Among People With Psychosis: A Randomized Clinical Trial

IMPORTANCE

Persistent paranoia is common among patients with psychosis. Cognitive-behavioral therapy for psychosis can be effective. However, challenges in engagement and effectiveness remain.

OBJECTIVE

To investigate the effects on paranoia and mechanisms of action of SlowMo, a digitally supported reasoning intervention, plus usual care compared with usual care only.

DESIGN, SETTING, AND PARTICIPANTS

This parallel-arm, assessor-blinded, randomized clinical trial recruited participants at UK community health services from May 1, 2017, to May 14, 2019. Eligible participants consisted of a referral sample with schizophrenia-spectrum psychosis and distressing, persistent (≥3 months) paranoia.

INTERVENTIONS

Individuals were randomized 1:1 to SlowMo, consisting of 8 digitally supported face-to-face sessions and a mobile app, plus usual care (n = 181) and usual care only (n = 181).

MAIN OUTCOMES AND MEASURES

The primary outcome was paranoia, measured by the Green et al Paranoid Thoughts Scale (GPTS) total score at 24 weeks. Secondary outcomes included GPTS total score at 12 weeks and GPTS Part A (reference) and Part B (persecutory) scores, the Psychotic Symptom Rating Scales (PSYRATS Delusion subscale), reasoning (belief flexibility, possibility of being mistaken [Maudsley Assessment of Delusions, rated 0%-100%]), and jumping to conclusions (Beads Task).

RESULTS

A total of 361 participants were included in intention-to-treat analysis, of whom 252 (69.8%) were male and 249 (69.0%) were White; the mean (SD) age was 42.6 (11.6) years. At 24 weeks, 332 participants (92.0%) provided primary outcome data. Of 181 participants in the SlowMo group, 145 (80.1%) completed therapy. SlowMo plus usual care was not associated with greater reductions than usual care in GPTS total score at 24 weeks (Cohen d, 0.20; 95% CI, -0.02 to 0.40; P = .06). There were significant effects on secondary paranoia outcomes at 12 weeks, including GPTS total score (Cohen d, 0.30; 95% CI, 0.09-0.51; P = .005), Part A score (Cohen d, 0.22; 95% CI, 0.06-0.39; P = .009), and Part B score (Cohen d, 0.32; 95% CI, 0.08-0.56; P = .009), and at 24 weeks, including Part B score (Cohen d, 0.25; 95% CI, 0.01-0.49; P = .04) but not Part A score (Cohen d, 0.12; 95% CI, -0.05 to 0.28; P = .18). Improvements were observed in an observer-rated measure of persecutory delusions (PSYRATS delusion) at 12 weeks (Cohen d, 0.47; 95% CI, 0.17-0.78; P = .002) and 24 weeks (Cohen d, 0.50; 95% CI, 0.20-0.80; P = .001) and belief flexibility at 12 weeks (Cohen d, 0.29; 95% CI, 0.09-0.49; P = .004) and 24 weeks (Cohen d, 0.28; 95% CI, 0.08-0.49; P = .005). There were no significant effects on jumping to conclusions. Improved belief flexibility and worry mediated paranoia change (range mediated, 36%-56%).

CONCLUSIONS AND RELEVANCE

SlowMo did not demonstrate significant improvements in the primary measure of paranoia at 24 weeks; however, a beneficial effect of SlowMo on paranoia was indicated by the results on the primary measure at an earlier point and on observer-rated paranoia and self-reported persecution at 12 and 24 weeks. Further work to optimize SlowMo's effects is warranted.

TRIAL REGISTRATION

isrctn.org Identifier: ISRCTN 32448671.

The jumping to conclusions reasoning bias as a cognitive factor contributing to psychosis progression and persistence: findings from NEMESIS-2

BACKGROUND

Contemporary models of psychosis implicate the importance of affective dysregulation and cognitive factors (e.g. biases and schemas) in the development and maintenance of psychotic symptoms, but studies testing proposed mechanisms remain limited. This study, uniquely using a prospective design, investigated whether the jumping to conclusions (JTC) reasoning bias contributes to psychosis progression and persistence.

METHODS

Data were derived from the second Netherlands Mental Health Survey and Incidence Study (NEMESIS-2). The Composite International Diagnostic Interview and an add-on instrument were used to assess affective dysregulation (i.e. depression, anxiety and mania) and psychotic experiences (PEs), respectively. The beads task was used to assess JTC bias. Time series analyses were conducted using data from T1 and T2 (N = 8666), excluding individuals who reported high psychosis levels at T0.

RESULTS

Although the prospective design resulted in low statistical power, the findings suggest that, compared to those without symptoms, individuals with lifetime affective dysregulation were more likely to progress from low/moderate psychosis levels (state of 'aberrant salience', one or two PEs) at T1 to high psychosis levels ('frank psychosis', three or more PEs or psychosis-related help-seeking behaviour) at T2 if the JTC bias was present [adj. relative risk ratio (RRR): 3.8, 95% confidence interval (CI) 0.8-18.6, p = 0.101]. Similarly, the JTC bias contributed to the persistence of high psychosis levels (adj. RRR: 12.7, 95% CI 0.7-239.6, p = 0.091).

CONCLUSIONS

We found some evidence that the JTC bias may contribute to psychosis progression and persistence in individuals with affective dysregulation. However, well-powered prospective studies are needed to replicate these findings.

Selective effects of serotonin on choices to gather more information

BACKGROUND

Gathering and evaluating information leads to better decisions, but often at cost. The balance between information seeking and exploitation features in neurodevelopmental, mood, psychotic and substance-related disorders. Serotonin's role has been highlighted by experimental reduction of its precursor, tryptophan.

AIMS

We tested the boundaries and applicability of this role by asking whether changes to information sampling would be observed following acute doses of serotonergic and catecholaminergic clinical treatments. We used a variant of the Information Sampling Task (IST) to measure how much information a person requires before they make a decision. This task allows participants to sample information until satisfied to make a choice.

METHODS

In separate double-blind placebo-controlled experiments, we tested 27 healthy participants on/off 20 mg of the serotonin reuptake inhibitor (SRI) citalopram, and 22 participants on/off 40 mg of the noradrenergic reuptake inhibitor atomoxetine. The IST variant minimised effects of temporal impulsivity and loss aversion. Analyses used a variety of participant prior expectations of sampling spaces in the IST, including a new prior that accounts for learning of likely states across trials. We analysed behaviour by a new method that also accounts for baseline individual differences of risk preference.

RESULTS

Baseline preferences demonstrated risk aversion. Citalopram decreased the expected utility of choices and probability of being correct based on informational content of samples collected, suggesting participants collected less useful information before making a choice. Atomoxetine did not influence information seeking.

CONCLUSION

Acute changes of serotonin activity by way of a single SRI dose alter information-seeking behaviour.

Assessing Impulsivity in Humans and Rodents: Taking the Translational Road

Impulsivity is a multidimensional construct encompassing domains of behavioral inhibition as well as of decision making. It is often adaptive and associated with fast responses, being in that sense physiological. However, abnormal manifestations of impulsive behavior can be observed in contexts of drug abuse and attention-deficit/hyperactivity disorder (ADHD), among others. A number of tools have therefore been devised to assess the different facets of impulsivity in both normal and pathological contexts. In this narrative review, we systematize behavioral and self-reported measures of impulsivity and critically discuss their constructs and limitations, establishing a parallel between assessments in humans and rodents. The first rely on paradigms that are typically designed to assess a specific dimension of impulsivity, within either impulsive action (inability to suppress a prepotent action) or impulsive choice, which implies a decision that weighs the costs and benefits of the options. On the other hand, self-reported measures are performed through questionnaires, allowing assessment of impulsivity dimensions that would be difficult to mimic in an experimental setting (e.g., positive/negative urgency and lack of premeditation) and which are therefore difficult (if not impossible) to measure in rodents.

Jumping to conclusions and suicidal behavior in depression and psychosis

Suicidal behavior (SB) involves an impairment in decision-making (DM). Jumping to conclusions bias (JTC), described as the tendency to make hasty decisions based on insufficient information, could be considered as analogous of impaired DM. However, the link between JTC and SB in psychosis and other diagnoses (e.g., depression) has never been studied. This study aims to explore the presence of JTC and SB in a sample comprising 121 patients with psychosis and 101 with depression. Sociodemographic and clinical data were collected, including history of SB and symptom-severity scores. JTC was assessed by the beads task, and patients who reached decisions with the second bead or before were considered to exhibit JTC. Age, gender, diagnosis, educational level, symptom severity, substance use, and SB were compared according to JTC presence. Variables found to be significantly different in this comparison were included in a multivariate analysis. JTC was more prevalent in patients with depression than with psychosis: 55.6% in an 85:15 ratio and 64.6% in a 60:40 ratio. When multivariate logistic regression was applied to study the influence of diagnosis (psychosis versus depression), age, and SB, only SB remained statistically significant (OR 2.05; 95% CI 0.99-4.22; p = 0.05). The population studied was assembled by grouping different samples from previous research, and we have not included control variables such as other clinical variables, neurocognitive measurements, or personality traits. JTC may be more closely linked to SB, as a transdiagnostic variable, rather than to a specific diagnosis.

The Interplay Between Postsynaptic Striatal D2/3 Receptor Availability, Adversity Exposure and Odd Beliefs: A [11C]-Raclopride PET Study

BACKGROUND

Between unaffected mental health and diagnosable psychiatric disorders, there is a vast continuum of functioning. The hypothesized link between striatal dopamine signaling and psychosis has guided a prolific body of research. However, it has been understudied in the context of multiple interacting factors, subclinical phenotypes, and pre-postsynaptic dynamics.

METHOD

This work investigated psychotic-like experiences and D2/3 dopamine postsynaptic receptor availability in the dorsal striatum, quantified by in vivo [11C]-raclopride positron emission tomography, in a sample of 24 healthy male individuals. Additional mediation and moderation effects with childhood trauma and key dopamine-regulating genes were examined.

RESULTS

An inverse relationship between nondisplaceable binding potential and subclinical symptoms was identified. D2/3 receptor availability in the left putamen fully mediated the association between traumatic childhood experiences and odd beliefs, that is, inclinations to see meaning in randomness and unfounded interpretations. Moreover, the effect of early adversity was moderated by a DRD2 functional variant (rs1076560). The results link environmental and neurobiological influences in the striatum to the origination of psychosis spectrum symptomology, consistent with the social defeat and diathesis-stress models.

CONCLUSIONS

Adversity exposure may affect the dopamine system as in association with biases in probabilistic reasoning, attributional style, and salience processing. The inverse relationship between D2/3 availability and symptomology may be explained by endogenous dopamine occupying the receptor, postsynaptic compensatory mechanisms, and/or altered receptor sensitivity. This may also reflect a cognitively stabilizing mechanism in non-help-seeking individuals. Future research should comprehensively characterize molecular parameters of dopamine neurotransmission along the psychosis spectrum and according to subtype profiling.

Taking others into account: combining directly experienced and indirect information in schizophrenia

An abnormality in inference, resulting in distorted internal models of the world, has been argued to be a common mechanism underlying the heterogeneous psychopathology in schizophrenia. However, findings have been mixed as to wherein the abnormality lies and have typically failed to find convincing relations to symptoms. The limited and inconsistent findings may have been due to methodological limitations of the experimental design, such as conflating other factors (e.g. comprehension) with the inferential process of interest, and a failure to adequately assess and model the key aspects of the inferential process. Here, we investigated probabilistic inference based on multiple sources of information using a new digital version of the beads task, framed in a social context. Thirty-five patients with schizophrenia or schizoaffective disorder with a wide range of symptoms and 40 matched healthy control subjects performed the task, where they guessed the colour of the next marble drawn from a jar based on a sample from the jar as well as the choices and the expressed confidence of four people, each with their own independent sample (which was hidden from participant view). We relied on theoretically motivated computational models to assess which model best captured the inferential process and investigated whether it could serve as a mechanistic model for both psychotic and negative symptoms. We found that 'circular inference' best described the inference process, where patients over-weighed and overcounted direct experience and under-weighed information from others. Crucially, overcounting of direct experience was uniquely associated with most psychotic and negative symptoms. In addition, patients with worse social cognitive function had more difficulties using others' confidence to inform their choices. This difficulty was related to worse real-world functioning. The findings could not be easily ascribed to differences in working memory, executive function, intelligence or antipsychotic medication. These results suggest hallucinations, delusions and negative symptoms could stem from a common underlying abnormality in inference, where directly experienced information is assigned an unreasonable weight and taken into account multiple times. By this, even unreliable first-hand experiences may gain disproportionate significance. The effect could lead to false perceptions (hallucinations), false beliefs (delusions) and deviant social behaviour (e.g. loss of interest in others, bizarre and inappropriate behaviour). This may be particularly problematic for patients with social cognitive deficits, as they may fail to make use of corrective information from others, ultimately leading to worse social functioning.

Overly Strong Priors for Socially Meaningful Visual Signals Are Linked to Psychosis Proneness in Healthy Individuals

According to the predictive coding theory of psychosis, hallucinations and delusions are explained by an overweighing of high-level prior expectations relative to sensory information that leads to false perceptions of meaningful signals. However, it is currently unclear whether the hypothesized overweighing of priors (1) represents a pervasive alteration that extends to the visual modality and (2) takes already effect at early automatic processing stages. Here, we addressed these questions by studying visual perception of socially meaningful stimuli in healthy individuals with varying degrees of psychosis proneness (n = 39). In a first task, we quantified participants' prior for detecting faces in visual noise using a Bayesian decision model. In a second task, we measured participants' prior for detecting direct gaze stimuli that were rendered invisible by continuous flash suppression. We found that the prior for detecting faces in noise correlated with hallucination proneness (r = 0.50, p = 0.001, Bayes factor 1/20.1) as well as delusion proneness (r = 0.46, p = 0.003, BF 1/9.4). The prior for detecting invisible direct gaze was significantly associated with hallucination proneness (r = 0.43, p = 0.009, BF 1/3.8) but not conclusively with delusion proneness (r = 0.30, p = 0.079, BF 1.7). Our results provide evidence for the idea that overly strong high-level priors for automatically detecting socially meaningful stimuli might constitute a processing alteration in psychosis.

Effects of traumatic life events, cognitive biases and variation in dopaminergic genes on psychosis proneness

AIMS

Recent studies have provided evidence that interactions between variation in dopaminergic genes and stressful experiences might impact risk of psychosis. However, it remains unknown whether these interactions impact the development of subclinical symptoms, including psychotic-like experiences (PLEs). In this study, we aimed to test the effects of interactions between variation in dopaminergic genes and traumatic life events (TLEs) on a severity of PLEs.

METHODS

We assessed TLEs, cognitive biases, PLEs as well as the catechol-O-methyltransferase (COMT) rs4680 and the dopamine D2 receptor (DRD2) rs6277 gene polymorphisms in 445 university students at three urban areas.

RESULTS

There was a significant effect of the interaction between the COMT rs4680 and a history of any type of TLEs on a severity of PLEs. Among the COMT rs4680 Met allele carriers, a severity of PLEs was higher in individuals with a history of any type of TLEs. Further stratification of the sample revealed that this effect appears only in the group of participants with a high level of cognitive biases. The DRD2 rs6277 C allele was independently associated with a higher level of PLEs.

CONCLUSIONS

Our results indicate that decreased dopamine catabolism related to the COMT gene polymorphism might increase psychosis proneness in individuals with a history of TLEs and high levels of cognitive biases. Variation in the DRD2 gene might exert independent effects on psychosis proneness. These findings imply that there are various levels of complexity in the models of interactions between genetic and environmental factors explaining the mechanisms underlying psychosis proneness.

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.

Jumping to conclusions, general intelligence, and psychosis liability: findings from the multi-centre EU-GEI case-control study

BACKGROUND

The 'jumping to conclusions' (JTC) bias is associated with both psychosis and general cognition but their relationship is unclear. In this study, we set out to clarify the relationship between the JTC bias, IQ, psychosis and polygenic liability to schizophrenia and IQ.

METHODS

A total of 817 first episode psychosis patients and 1294 population-based controls completed assessments of general intelligence (IQ), and JTC, and provided blood or saliva samples from which we extracted DNA and computed polygenic risk scores for IQ and schizophrenia.

RESULTS

The estimated proportion of the total effect of case/control differences on JTC mediated by IQ was 79%. Schizophrenia polygenic risk score was non-significantly associated with a higher number of beads drawn (B = 0.47, 95% CI -0.21 to 1.16, p = 0.17); whereas IQ PRS (B = 0.51, 95% CI 0.25-0.76, p < 0.001) significantly predicted the number of beads drawn, and was thus associated with reduced JTC bias. The JTC was more strongly associated with the higher level of psychotic-like experiences (PLEs) in controls, including after controlling for IQ (B = -1.7, 95% CI -2.8 to -0.5, p = 0.006), but did not relate to delusions in patients.

CONCLUSIONS

Our findings suggest that the JTC reasoning bias in psychosis might not be a specific cognitive deficit but rather a manifestation or consequence, of general cognitive impairment. Whereas, in the general population, the JTC bias is related to PLEs, independent of IQ. The work has the potential to inform interventions targeting cognitive biases in early psychosis.

The centrality of secure attachment within an interacting network of symptoms, cognition, and attachment dimensions in persons with schizophrenia-spectrum disorders: A preliminary study

BACKGROUND

Research in the field of psychosis broadly suggests that symptoms, neurocognitive deficits, social cognition, cognitive biases, and attachment experiences influence each other. However, little is known if any of these constructions play a more central role than others as they interact.

METHOD

To clarify this issue, we conducted a "network" analysis to explore the interplay among a set of variables related to attachment, cognition domains, and psychotic symptoms in a small sample of outpatients with stabilised schizophrenia-spectrum disorders (n = 25). Eighteen participants (72%) were first-episode patients. We assessed psychotic symptoms, attachment dimensions, neurocognitive performance, "theory of mind", emotion recognition, and "jumping to conclusions" bias using standardised instruments.

RESULTS

The study provides preliminary evidence about a network structure in which the secure attachment (SA) is the most central "node" within the interacting network considering all centrality measures, followed by general psychopathology. SA was closely connected to self-sufficiency (avoidant attachment) and child traumatism, as well as with neurocognition. Emotion recognition impairment was the most robust connection to positive symptoms and mediated the influence of SA on psychotic symptoms.

CONCLUSIONS

Beyond the importance of symptoms, our results, although preliminary, suggest the need to assess attachment experiences and cognition domains to improve specific interventions that can promote recovery in outpatients with psychosis.

Childhood trauma and cognitive biases associated with psychosis: A systematic review and meta-analysis

Childhood trauma is associated with an increased risk of psychosis, but the mechanisms that mediate this relationship are unknown. Exposure to trauma has been hypothesised to lead to cognitive biases that might have causal effects on psychotic symptoms. The literature on whether childhood trauma is associated with psychosis-related cognitive biases has not been comprehensively reviewed. A systematic review and meta-analysis or narrative synthesis of studies examining the association between childhood trauma and the following biases: external locus of control (LOC), external attribution, probabilistic reasoning, source monitoring, top-down processing, and bias against disconfirmatory evidence. Studies were assessed for quality, and sources of heterogeneity were explored. We included 25 studies from 3,465 studies identified. Individuals exposed to childhood trauma reported a more external LOC (14 studies: SMD Median = 0.40, Interquartile range 0.07 to 0.52), consistent with a narrative synthesis of 11 other studies of LOC. There was substantial heterogeneity in the meta-analysis (I2 = 93%) not explained by study characteristics examined. Narrative syntheses for other biases showed weaker, or no evidence of association with trauma. The quality of included studies was generally low. Our review provides some evidence of an association between childhood trauma and a more external LOC, but not with the other biases examined. The low quality and paucity of studies for most of the cognitive biases examined highlights the need for more rigorous studies to determine which biases occur after trauma, and whether they mediate an effect of childhood trauma on psychosis.

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.

Persecutory ideation and anomalous perceptual experiences in the context of the COVID-19 outbreak in France: what's left one month later?

PURPOSE

Beyond the effects of the coronavirus pandemic on the public's health, the length of lockdown and its possible psychological impacts on populations is heavily debated. However, the consequences of lockdown on psychotic symptoms have been poorly investigated.

METHODS

An online survey was run from April 13 to May 11, 2020; a total of 728 French subjects from the general population were included in the study. We assessed the perceived impact of the COVID-19 outbreak, length of isolation, diagnosis/symptoms/hospitalisation related to the COVID-19 (oneself and family). Paranoid ideations and hallucination-like experiences were assessed via the Paranoia Scale and the Cardiff Anomalous Perceptions Scale, respectively. Self-reported measures of negative affect, loneliness, sleep difficulties, jumping to conclusion bias, repetitive thoughts, among others, were also included.

RESULTS

Final regression model for paranoia indicated that socio-demographic variables (age, sex and education), loneliness, cognitive bias, anxiety, experiential avoidance, repetitive thoughts and hallucinations were associated with paranoia (R² = 0.43). For hallucinations, clinical variables as well as the quality of sleep, behavioural activation, repetitive thoughts, anxiety and paranoia were associated with hallucinations in our sample (R² = 0.27). Neither length of isolation nor the perceived impact of the COVID-19 pandemic were associated with psychotic experiences in the final models.

CONCLUSIONS

No evidence was found for the impact of isolation on psychotic symptoms in the general population in France one month after the lockdown. It nevertheless confirms the preeminent role of several factors previously described in the maintenance and development of psychotic symptoms in the context of a pandemic and lockdown measures.

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.

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.

Sleep problems and worrying precede psychotic symptoms during an online intervention for psychosis

OBJECTIVE

Experience sampling assessments (multiple assessments per day for approximately one week) indicate that positive symptoms fluctuate over time in psychosis. Precursors, such as sleep problems or worrying, predict these fluctuations. To date, it remains unclear whether the same precursors predict symptom variability also during treatment in an online intervention for psychosis, using assessments lying temporally further apart.

METHODS

Participants completed brief intermediate online self-report assessments on their computers (up to every 7 days during a 2-month waiting period and up to twice every 6 days during a 2-month intervention period) within a randomized controlled trial. We monitored the course of paranoia, auditory verbal hallucinations, and their theory-driven precursors worrying, negative affect, self-esteem, self-reported cognitive biases, and quality of sleep in n = 124 participants (M = 10.32 assessments per participant; SD = 6.07). We tested group differences regarding the course of the composite of precursors, group differences regarding the effect of the composite on subsequent momentary psychotic symptoms, and the effect of each individual precursor on subsequent psychotic symptoms, using (lagged) linear mixed models.

RESULTS

The course composite precursors over time and their lagged effect on subsequent momentary psychotic symptoms did not differ between groups. During the intervention, increased worrying and decreased quality of sleep preceded heightened momentary psychotic symptoms.

CONCLUSION

The regression-based design does not allow drawing causal conclusions. However, worrying and sleep problems likely represent underlying mechanisms of psychotic symptom variability during online psychosis treatment, indicating that experience sampling findings from everyday life generalize to interventions with assessments lying several days apart.

PRACTITIONER POINTS

Worrying and sleep problems represent important mechanisms of symptom fluctuations during an online intervention for people with psychosis. Our findings further support the notion that worrying and sleep problems are important treatment targets in psychological interventions for people with psychosis. Momentary levels of worrying and quality of sleep can signal subsequent fluctuations of psychotic symptom severity so practitioners should monitor these variables during treatment. Worrying seems to predict subsequent paranoia specifically during treatment whereas quality of sleep predicts both paranoia and auditory verbal hallucinations.

Cognitive Insight in First-Episode Psychosis: Changes during Metacognitive Training

Background: Metacognitive training (MCT) has demonstrated its efficacy in psychosis. However, the effect of each MCT session has not been studied. The aim of the study was to assess changes in cognitive insight after MCT: (a) between baseline, post-treatment, and follow-up; (b) after each session of the MCT controlled for intellectual quotient (IQ) and educational level. Method: A total of 65 patients with first-episode psychosis were included in the MCT group from nine centers of Spain. Patients were assessed at baseline, post-treatment, and 6 months follow-up, as well as after each session of MCT with the Beck Cognitive Insight Scale (BCIS). The BCIS contains two subscales: self-reflectiveness and self-certainty, and the Composite Index. Statistical analysis was performed using linear mixed models with repeated measures at different time points. Results: Self-certainty decreased significantly (p = 0.03) over time and the effect of IQ was negative and significant (p = 0.02). From session 4 to session 8, all sessions improved cognitive insight by significantly reducing self-certainty and the Composite Index. Conclusions: MCT intervention appears to have beneficial effects on cognitive insight by reducing self-certainty, especially after four sessions. Moreover, a minimum IQ is required to ensure benefits from MCT group intervention.

Problems in measuring the JTC-bias in patients with psychotic disorders with the fish task: a secondary analysis of a baseline assessment of a randomized controlled trial

BACKGROUND

The jumping to conclusions bias (JTC) is considered to be an important causal factor in theoretical models for the formation and maintenance of delusions. However, recent meta-analytic findings show a rather equivocal pattern of results regarding associations between JTC and delusions. Thus, the present study aims to investigate in a large sample whether the JTC-bias is more pronounced in patients with psychotic disorders in comparison to controls and whether the JTC bias is associated with a more severe delusional conviction, persecutory delusions, and positive symptoms in general.

METHODS

Patients with psychotic disorders (n = 300) enrolled in a therapy trial and healthy controls (n = 51) conducted a variant of the beads task (fish task) as a measure for the JTC-bias at the start of the trial. Further, clinical interviews were used to assess patients' delusional severity and delusional conviction.

RESULTS

There were no statistically significant differences between patients with psychotic disorders (with 53% displaying the JTC-bias) and controls (41%). Furthermore, there were no statistically significant correlations between JTC measures and persecutory delusions, delusional conviction, and positive symptoms.

CONCLUSIONS

We found no differences in JTC between patients with psychotic disorders and healthy controls, which is in part in line with meta-analytic findings using a wide range of JTC task variants. Interestingly, patients with psychotic disorders displayed JTC rates commonly found in the literature, while healthy control subjects showed an unexpectedly high level of JTC. The task variant we used in the present study (fish task) is discussed as a potential reason for our results, as it may induce a more deliberative reasoning style in controls as compared to the traditional beads task. Furthermore, possible implications for the measurement of the JTC-bias, in general, are discussed.

TRIAL REGISTRATION

ISRCTN29242879 ( isrctn.com ), date of registration: April 12th 2006, retrospectively registered.

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.

Glutamatergic Contribution to Probabilistic Reasoning and Jumping to Conclusions in Schizophrenia: A Double-Blind, Randomized Experimental Trial

BACKGROUND

Impaired probabilistic reasoning and the jumping-to-conclusions reasoning bias are hallmark features of schizophrenia (SCZ), yet the neuropharmacological basis of these deficits remains unclear. Here we tested the hypothesis that glutamatergic neurotransmission specifically contributes to jumping to conclusions and impaired probabilistic reasoning in SCZ.

METHODS

A total of 192 healthy participants received either NMDA receptor agonists/antagonists (D-cycloserine/dextromethorphan), dopamine type 2 receptor agonists/antagonists (bromocriptine/haloperidol), or placebo in a randomized, double-blind, between-subjects design. In addition, we tested 32 healthy control participants matched to 32 psychotic inpatients with SCZ-a state associated with compromised probabilistic reasoning due to reduced glutamatergic neurotransmission. All experiments employed two versions of a probabilistic reasoning (beads) task, which required participants to either sample individual amounts of sensory information to infer correct decisions or provide explicit probability estimates for presented sensory information. Our task instantiations assessed both information sampling and explicit probability estimates in different probabilistic contexts (easy vs. difficult conditions) and changing sensory information through random transitions among easy, difficult, and ambiguous trial types.

RESULTS

Following administration of D-cycloserine, haloperidol, and bromocriptine, healthy participants displayed data-gathering behavior that was normal compared with placebo and was adequate in the context of all employed task conditions and trial level difficulties. However, healthy participants receiving dextromethorphan displayed a jumping-to-conclusions bias, abnormally increased probability estimates, and overweighting of sensory information. These effects were mirrored in patients with SCZ performing the same versions of the beads task.

CONCLUSIONS

Our findings provide novel neuropharmacological evidence linking reduced glutamatergic neurotransmission to impaired information sampling and to disrupted probabilistic reasoning, namely to overweighting of sensory evidence, in patients with SCZ.

Time will tell: Decision making in premanifest and manifest Huntington's disease

OBJECTIVE

To investigate cognitive flexibility in premanifest and manifest Huntington's disease (HD).

BACKGROUND

HD is an autosomal dominant neurodegenerative disease characterized by motor, cognitive, and behavioral abnormalities with typical motor symptoms. In this study, we wanted to assess decision making in premanifest (pre-HD) and manifest HD patients.

METHODS

A total of 77 non-demented subjects including 29 pre-HD, 22 manifest HD patients, and 26 healthy controls (HC) were included. We stratified the pre-HD group based on their estimated years to disease onset into a far (FAR, n = 13) and a near (NEAR, n = 16) group. Furthermore, participants performed the Montreal cognitive assessment battery (MoCA), the trail making task part A and B (TMT A, TMT B), the Symbol digit modalities test (SDMT), and the beads task.

RESULTS

In the beads task, HD patients gathered less information than all other groups (all p-values < .001). Furthermore, the NEAR group gathered less information than the FAR group (p < .001) and HC (p = .001). There was no difference between the HC and the FAR group (p = 1.0). In the TMT and the SDMT, HD patients were slower than all other groups (all p-values < .01) but there were no other significant differences.

CONCLUSIONS

Decision making with a higher degree of uncertainty may be an early neuropsychological sign to indicate the disease process prior to reaching criteria for motor diagnosis of HD.

A comprehensive meta-analysis of the self-serving bias in schizophrenia spectrum disorders compared to non-clinical subjects

We conducted a comprehensive meta-analysis to investigate the self-serving bias SSB in schizophrenia spectrum disorders (SSD) to examine its specificity for persecutory delusions, paranoia, and to explore sources of heterogeneity in previous findings. We included 56 studies with n = 2501 patients with SSD and n = 2601 non-clinical controls in the main random-effects model using Hedges' g. Data quality and risk of bias were assessed. Results showed that SSB was a function of the method of measurement, and the cultural background of the participants, thereby identifying important sources of heterogeneity in measuring SSB in patients with SSD. The SSD group was somewhat more prone to SSB (g = 0.17), especially, when in a state of active persecutory delusion (g = 0.32/0.57), when they scored high in paranoid ideation (r = 0.25), or tended to jump to conclusions (r = 0.43). High self-esteem in the SSD group was associated with high SSB (r = 0.34); depression with low SSB (r=-0.39).

Emotion-Regulation in Psychosis: Patients with Psychotic Disorders Apply Reappraisal Successfully

Background

Emotion-regulation is assumed to be impaired in psychosis: patients with psychotic disorders (PD) self-report to use reappraisal less frequently than healthy controls (HC), but it is uncertain whether they are also less successful in applying reappraisal. Moreover, it has not been investigated whether the habitual use of reappraisal is associated with the ability to use reappraisal successfully.

Methods

To address these questions, PD (n = 60), a clinical control group of patients with anxiety disorders (AD; n = 40) and HC (n = 40) completed questionnaires on habitual emotion-regulation and alexithymia, performed tests on neurocognitive functioning and jumping-to-conclusion bias, and were subjected to an emotion-regulation paradigm, in which they were asked to down-regulate induced anxiety and sadness.

Results

No differences were found between PD and HC regarding the habitual use of reappraisal, but PD reported to use reappraisal more frequently than AD. All groups were able to down-regulate anxiety and sadness via reappraisal following instructions. The habitual use of reappraisal and the reduction of anxiety and sadness after instruction were uncorrelated.

Conclusion

These findings question the common assumption that PD use reappraisal less often or less successfully. At least under laboratory condition, PD do not appear to be impaired in reducing negative affect via reappraisal successfully.

Thinking Preferences and Conspiracy Belief: Intuitive Thinking and the Jumping to Conclusions-Bias as a Basis for the Belief in Conspiracy Theories

BACKGROUND

The belief in conspiracy theories and paranoid ideation are often treated as almost synonymous. However, there is to date no research concerning shared underlying cognitive underpinnings of belief in conspiracy theories and paranoid ideation. One potential underlying factor could be the well-known jumping to conclusion (JTC) bias, the tendency of persons with delusions to perform hasty decisions that are sometimes based on little evidence. Furthermore, a preference for a more intuitive general thinking style, as opposed to an analytical thinking style, could be an additional underlying cognitive factor of both conspiracy theories and paranoia. Thus, the aim of the present study is to investigate in a large sample of non-clinical individuals whether the JTC-bias is more pronounced in individuals who display a stronger belief in conspiracy theories and whether both are related to a more intuitive thinking preference.

METHODS

We assessed the data of 519 non-clinical individuals regarding their respective approval of 20 specific conspiracy theories in an online study. Further, we assessed the JTC-bias by using a computerized variant of the beads task (fish task). Thinking preferences were measured with the Rational-Experiential Interview.

RESULTS

Subjects who displayed the JTC-bias presented a more pronounced belief in conspiracy theories. In addition, gathering little information in the fish task before performing a decision (less draws to decision) was related to a stronger endorsement of conspiracy theories and a more intuitive thinking style (and a less analytic thinking style). Finally, a preference for intuitive thinking predicted a stronger belief in conspiracy theories in a multiple regression analysis.

CONCLUSIONS

Our results demonstrate the implication of a preference for an intuitive thinking style accompanied by a propensity to faster decision-making (JTC-bias) as possible cognitive underpinnings of beliefs in conspiracy theories. Furthermore, our study is the first to confirm the notion of the JTC-bias as a reflection of the use of an intuitive thinking style.

The Role of Inner Speech in Executive Functioning Tasks: Schizophrenia With Auditory Verbal Hallucinations and Autistic Spectrum Conditions as Case Studies

Several theories propose that one of the core functions of inner speech (IS) is to support subjects in the completion of cognitively effortful tasks, especially those involving executive functions (EF). In this paper we focus on two populations who notoriously encounter difficulties in performing EF tasks, namely, people diagnosed with schizophrenia who experience auditory verbal hallucinations (Sz-AVH) and people with autism spectrum conditions (ASC). We focus on these two populations because they represent two different ways in which IS can fail to help in EF tasks, which can be illustrative for other mental conditions. First, we review the main components of EF (see section "Executive Functions"). Then we explain the functions that IS is taken to perform in the domain of EF (see section "Inner Speech and Executive Functions") and review the evidence concerning problems about EF in the two populations of our study: Sz-AVH (see section "Executive Functions and Inner Speech in Sz-AVH") and ASC (see section "Executive Function and Inner Speech in ASC"). After this we further detail our account about what a properly functioning IS can do for both populations and how different IS profiles may impact EF performance: in the case of Sz-AVH, the uncontrolled and intrusive character of IS negatively affects EF performance, whereas in ASC, EF is not sufficiently supported by IS, given the tendency in this population to present a diminished use of IS (see section "IS in ASC and Sz-AVH: How It Relates to EF"). We finally briefly discuss Attention Deficit/Hyperactivity Disorder (ADHD) and Developmental Language Disorders (DLD) (see section "Further Considerations").

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.

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 (r_s = 0.38), ETB (r_s = 0.35), BIB (r_s = 0.19), JTC (r_s = 0.10), and personalizing (r_s = 0.24). In community samples, PPLEs were positively associated with ASB (r_s = 0.62), ATB (r_s = 0.34), ETB (r_s = 0.36), BIB (r_s = 0.18), JTC (r_s = 0.11). In addition, negative PLEs were positively associated with ATB (r_s = 0.28), ETB (r_s = 0.37), BIB (r_s = 0.19) and ASB (r_s = 0.18). In UHR samples, positive associations were established between PPLEs and ATB (rs = 0.47), ETB (rs = 0.34), personalizing (r_s = 0.36) and the aggression bias (r_s = 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.

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).

Measuring Reasoning in Paranoia: Development of the Fast and Slow Thinking Questionnaire

Paranoid thoughts are common across the psychosis continuum. It is well established that reasoning biases (conceived as an overreliance on fast thinking and lack of willingness and/or ability to engage in slow thinking) contribute to paranoia. Targeted therapies have shown promise in improving reasoning in order to reduce paranoia. Psychometrically robust and easy-to-use measures of these thinking styles will assist research and clinical practice. Existing assessments include experimental tasks that are complex to administer or self-report measures that have limitations in comprehensively assessing cognitive biases in paranoia. We have developed the first questionnaire to assess fast and slow thinking biases related to paranoid thoughts, and here report on its evaluation. In study 1, we generated, evaluated, and extracted items reflecting reasoning, and assessed their reliability and validity in a non-clinical sample (n = 209). In study 2, we replicated the factor analysis and psychometric evaluation in a clinical sample (n = 265). The resultant Fast and Slow Thinking (FaST) questionnaire consists of two 5-item scales reflecting fast and slow thinking and is therefore brief and suitable for use in both research and clinical practice. The fast thinking scale is reliable and valid. Reliability and criterion validity of the slow scale shows promise. It had limited construct validity with objective reasoning assessments in the clinical group, possibly due to impaired meta-cognitive awareness of slow thinking. We recommend the FaST questionnaire as a new tool for improving understanding of reasoning biases in paranoia and supporting targeted psychological therapies.

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.