Data gathering: biased in psychosis?

Undoubtedly unaware of homonymous hemianopia: The contribution of overconfidence to anosognosia of hemianopia

A new functional deficit caused by a stroke can be understood as a situation of uncertainty that has to prompt deficit discovery and subsequent incorporation into an altered self-perception. Anosognosia for visual field deficits is frequent after stroke. For hemiplegia, patients' performance in a riddle test provided evidence that the inability to generate and adjust beliefs in face of uncertainty contributes to anosognosia for hemiplegia. In this prospective study, the same riddles are used in patients with homonymous hemianopia due to a first-ever stroke in the posterior cerebral artery territory and in an age-matched control cohort. The riddles create a situation of uncertainty that is resolved with five successive clues which progressively delimit the target word. After each clue, patients have to guess the target word and rate their confidence in the answer's correctness. Patients were tested once during the hospital stay. According to the Bisiach score for anosognosia, 12 out of 29 patients were unaware of their visual field deficits. All patients with anosognosia for hemianopia had right hemisphere lesions. Patients with and without anosognosia did not differ significantly in global cognitive impairment, mental flexibility or memory function. Importantly, patients with anosognosia showed higher confidence ratings than patients without anosognosia and controls in the first two clues (situations of uncertainty). This was demonstrated by a significant interaction effect in a mixed ANOVA with the factors group (anosognosia, nosognosia, controls) and riddle clues. An exploratory lesion subtraction analysis showed a high proportion of deficit unawareness in patients with lesions in the right fusiform and (para)hippocampal gyri. Our findings suggest that overconfidence in situations of uncertainty might contribute to the appearance of anosognosia for hemianopia. Because this has been demonstrated before in anosognosia for hemiplegia, we suggest that overconfidence is a supra-modal contributor to deficit unawareness.

Cognitive biases are associated with aberrant salience experience in schizophrenia spectrum disorders

INTRODUCTION

Cognitive models suggest the co-occurrence of cognitive biases and aberrant salience is unique to psychosis, but their interaction is not yet fully understood. Therefore, we aimed to elucidate the relationship between subjective cognitive biases and aberrant salience in individuals with schizophrenia spectrum disorders (SSDs) in this study.

METHODS

A sample of 92 subjects with SSDs underwent an assessment using Davos Assessment Cognitive Biases (DACOBS) and the Aberrant Salience Inventory (ASI) in a cross-sectional design. We evaluated psychopathological differences based on ASI scores and conducted a linear regression analysis to examine the variables associated with aberrant salience.

RESULTS

Subjects with an ASI score ≥14 demonstrated significantly higher scores across all subscales and total score of ASI and DACOBS (p<0.001). ASI subscales were significantly positive correlated with all DACOBS subscales, ranging from 0.250 for Increased Significance and Safety Behavior to 0.679 for Heightened Emotionality and Social cognition problems. The linear regression analysis revealed a positive association between aberrant salience and the DACOBS subscales jumping to conclusions (JTC) (β=0.220), social cognition problems (β=0.442), subjective cognitive problems (β=0.405), and a negative association with the subscale belief inflexibility (β=-0.350).

CONCLUSIONS

Our findings suggest that JTC, social cognition problems and subjective cognitive problems may play a central role in the experience of aberrant salience in individuals with SSDs. This work informs about the need of developing prevention and intervention strategies that specifically target cognitive biases and aberrant salience in the treatment of psychosis.

Examining the influence of self-referential thinking on aberrant salience and jumping to conclusions bias in individuals with schizophrenia-spectrum disorders

BACKGROUND AND OBJECTIVES

Cognitive processes such as aberrant salience and the jumping to conclusions (JTC) bias are implicated in the development of delusions. Self-referential thinking is implicated in this process; however, it is unknown how it may interact with aberrant salience and JTC bias in individuals with schizophrenia-spectrum disorders (SSDs). This study examined associations of self-referential thinking with aberrant salience, JTC bias, and delusion severity, and whether self-referential stimuli led to an increase in aberrant salience and JTC bias in SSDs (n = 20) relative to psychiatrically healthy controls (n = 20).

METHODS

To assess aberrant salience and JTC bias, participants were asked to complete both self-referential and neutral versions of the Salience Attribution Test (SAT) and the Beads Task, as well as self-report measures of aberrant salience and JTC bias.

RESULTS

Self-referential task condition interacted with clinical group to predict JTC beads task scores, such that participants with SSDs exhibited greater levels of JTC bias than psychiatrically healthy controls during the neutral task condition, when controlling for levels of motivation, cognitive insight, and functioning. Self-referential thinking was significantly associated with aberrant salience, JTC bias, and delusion severity.

LIMITATIONS

This experiment examined trait-level relationships between variables, so does not provide information about state-level interrelationships and would benefit from replication using more dynamic methods such as ecological momentary assessment.

CONCLUSIONS

These findings highlight the interrelationships between self-referential thinking, JTC bias, aberrant salience, and delusion severity, in individuals with SSDs, and support the interactive role of self-referential thinking in predicting JTC bias.

A Bayesian model of the jumping-to-conclusions bias and its relationship to psychopathology

The mechanisms by which delusion and anxiety affect the tendency to make hasty decisions (Jumping-to-Conclusions bias) remain unclear. This paper proposes a Bayesian computational model that explores the assignment of evidence weights as a potential explanation of the Jumping-to-Conclusions bias using the Beads Task. We also investigate the Beads Task as a repeated measure by varying the key aspects of the paradigm. The Bayesian model estimations from two online studies showed that higher delusional ideation promoted reduced belief updating but the impact of general and social anxiety on evidence weighting was inconsistent. The altered evidence weighting as a result of a psychopathological trait appeared insufficient in contributing to the Jumping-to-Conclusions bias. Variations in Beads Task aspects significantly affected subjective certainty at the point of decisions but not the number of draws to decisions. Repetitions of the Beads Task are feasible if one assesses the Jumping-to-Conclusions bias using number of draws to decisions.

A systematic review of performance-based assessment studies on cognitive biases in schizophrenia spectrum psychoses and clinical high-risk states: A summary of 40 years of research

Cognitive models of psychosis have stimulated empirical studies on cognitive biases involved in schizophrenia spectrum psychoses and their symptoms. This systematic review aimed to summarize the studies on the role of cognitive biases as assessed in different performance-based tasks in schizophrenia spectrum psychoses and clinical high-risk states. We focused on five cognitive biases linked to psychosis, i.e., aberrant salience, attentional biases, source monitoring biases, jumping to conclusions, and bias against disconfirmatory evidence. We identified N = 324 studies published in N = 308 articles fulfilling inclusion criteria. Most studies have been cross-sectional and confirmed that the schizophrenia spectrum psychoses are related to exaggerated cognitive biases compared to healthy controls. On the contrary, less evidence suggests a higher tendency for cognitive biases in the UHR sample. The only exceptions were source monitoring and jumping to conclusions, which were confirmed to be exaggerated in both clinical groups. Hallucinations and delusions were the most frequent symptoms studied in the context of cognitive biases. Based on the findings, we presented a hypothetical model on the role of interactions between cognitive biases or additive effects of biases in shaping the risk of psychosis. Future research is warranted for further development of cognitive models for psychosis.

Jumping to conclusions bias, psychosis and impulsivity in early stages of Parkinson's disease

OBJECTIVES

The aim was to explore the correlations between Jumping to Conclusions (JtC) tendency and neuropsychiatric features in patients with early Parkinson's disease (PD).

BACKGROUND

According to few reports, PD patients with impulsive-compulsive behaviors (ICBs) are prone to working memory difficulties including JtC bias. The correlation of psychotic features and JtC tendency remains still unclear.

METHODS

Healthy controls and patients within 3 years of PD onset were recruited. Participants were examined for psychotic symptoms using a 10 question PD-specific psychosis severity scale. JtC was measured by a probalistic reasoning scenario (beads task). In PD group, medication use, motor and non-motor symptoms were documented. Impulsivity was evaluated using the Questionnaire for Impulsive-Compulsive Disorders in PD (QUIP).

RESULTS

The prevalence of JtC bias was 9% (6/70) in healthy individuals, compared to 32% (22/68) of PD group [p = 0.001]. No association was detected between the presence of JtC tendency and PD-associated psychosis (p = 0.216). Patients with JtC had shorter duration of PD, more tremor-dominant PD subtype and higher QUIP scores, regardless of the dopaminergic therapy (p = 0.043, p = 0.015, p = 0.007, respectively). A trend towards attention and inhibition control deficit was noticed in JtC patients.

CONCLUSIONS

We found a high prevalence of JtC bias in early, cognitively intact PD population and a potential link between subthreshold ICBs and poor performance on beads task. Additional studies are needed to confirm our results and elaborate on the mechanisms that correlate impulsivity with JtC tendency, which are likely to be different from those mediating psychotic features in early PD.

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

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

Whodunit - A novel video-based task for the measurement of jumping to conclusions in the schizophrenia spectrum

Jumping to conclusions (JTC) is implicated in the formation and maintenance of the positive symptoms of psychosis and over the years has become a prominent treatment target. Yet, measures designed to detect JTC are compromised by a number of limitations. We aimed to address some of these shortcomings with a new video-based "Whodunit task" among participants scoring high and low on the Community Assessment of Psychic Experiences (CAPE). We recruited a large sample (N = 979) from the general population who were divided into subgroups high vs. low on psychotic-like experiences (PLE), matched for depression and background characteristics. In the Whodunit task, participants were asked to rate the likelihood that one out of six suspects was the perpetrator of a crime (deliberately ambiguous with no clear clues until the end). The primary measure was the number of sequences-to-decision (STD). In line with the hypothesis, participants scoring high on the CAPE positive subscale displayed significantly lower STD and a higher rate of JTC. Response confidence in the assessments was elevated in the PLE-High group. The number of overall decisions was also significantly elevated for the PLE-High group. No group differences were found when comparing those scoring high versus low on depression. The STD index correlated significantly with a corresponding index from another JTC task. The study presents a new paradigm for the measurement of data gathering in the schizophrenia spectrum. Speaking to its validity, the Whodunit task was correlated with another JTC measure. Future research should test abbreviated versions of the paradigm, preferably using multiple trials with differing topics/emotional themes.

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

BACKGROUND

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

DESIGN

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

RESULTS

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

CONCLUSIONS

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

A replication study of JTC bias, genetic liability for psychosis and delusional ideation

BACKGROUND

This study attempted to replicate whether a bias in probabilistic reasoning, or 'jumping to conclusions'(JTC) bias is associated with being a sibling of a patient with schizophrenia spectrum disorder; and if so, whether this association is contingent on subthreshold delusional ideation.

METHODS

Data were derived from the EUGEI project, a 25-centre, 15-country effort to study psychosis spectrum disorder. The current analyses included 1261 patients with schizophrenia spectrum disorder, 1282 siblings of patients and 1525 healthy comparison subjects, recruited in Spain (five centres), Turkey (three centres) and Serbia (one centre). The beads task was used to assess JTC bias. Lifetime experience of delusional ideation and hallucinatory experiences was assessed using the Community Assessment of Psychic Experiences. General cognitive abilities were taken into account in the analyses.

RESULTS

JTC bias was positively associated not only with patient status but also with sibling status [adjusted relative risk (aRR) ratio : 4.23 CI 95% 3.46-5.17 for siblings and aRR: 5.07 CI 95% 4.13-6.23 for patients]. The association between JTC bias and sibling status was stronger in those with higher levels of delusional ideation (aRR interaction in siblings: 3.77 CI 95% 1.67-8.51, and in patients: 2.15 CI 95% 0.94-4.92). The association between JTC bias and sibling status was not stronger in those with higher levels of hallucinatory experiences.

CONCLUSIONS

These findings replicate earlier findings that JTC bias is associated with familial liability for psychosis and that this is contingent on the degree of delusional ideation but not hallucinations.

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.

Relationship between jumping to conclusions and clinical outcomes in people at clinical high-risk for psychosis

BACKGROUND

Psychosis is associated with a reasoning bias, which manifests as a tendency to 'jump to conclusions'. We examined this bias in people at clinical high-risk for psychosis (CHR) and investigated its relationship with their clinical outcomes.

METHODS

In total, 303 CHR subjects and 57 healthy controls (HC) were included. Both groups were assessed at baseline, and after 1 and 2 years. A 'beads' task was used to assess reasoning bias. Symptoms and level of functioning were assessed using the Comprehensive Assessment of At-Risk Mental States scale (CAARMS) and the Global Assessment of Functioning (GAF), respectively. During follow up, 58 (16.1%) of the CHR group developed psychosis (CHR-T), and 245 did not (CHR-NT). Logistic regressions, multilevel mixed models, and Cox regression were used to analyse the relationship between reasoning bias and transition to psychosis and level of functioning, at each time point.

RESULTS

There was no association between reasoning bias at baseline and the subsequent onset of psychosis. However, when assessed after the transition to psychosis, CHR-T participants showed a greater tendency to jump to conclusions than CHR-NT and HC participants (55, 17, 17%; χ2 = 8.13, p = 0.012). There was a significant association between jumping to conclusions (JTC) at baseline and a reduced level of functioning at 2-year follow-up in the CHR group after adjusting for transition, gender, ethnicity, age, and IQ.

CONCLUSIONS

In CHR participants, JTC at baseline was associated with adverse functioning at the follow-up. Interventions designed to improve JTC could be beneficial in the CHR population.

People with schizophrenia use less information to interpret ambiguous social situations

BACKGROUND AND OBJECTIVES

The tendency of people with schizophrenia to gather insufficient information before making decisions or jumping to conclusions has been repeatedly reported. However, criticism has also been expressed regarding the ecological validity of this finding. Here we present the results obtained by a group of people with schizophrenia and a control group in a non-probabilistic task that requires obtaining items of information before interpreting an ambiguous social situation.

METHODS

Patients with schizophrenia (n = 48) and controls (n = 44) aged 18-50 years participated in the study. All subjects completed the Beads Task and the modified Social Information Preference Task.

RESULTS

Patients with schizophrenia showed a statistically significant tendency to jump to conclusions, including in the proposed novel social task. Unlike other studies, we were unable to find a relationship between this bias and greater severity of psychotic symptoms.

LIMITATIONS

We did not include patients with high levels of psychotic symptoms or a clinical control group.

CONCLUSIONS

The tendency to jump to conclusions in schizophrenia could be present in everyday interpersonal situations.

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.

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.

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.

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.

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.

Replicated evidence that endophenotypic expression of schizophrenia polygenic risk is greater in healthy siblings of patients compared to controls, suggesting gene-environment interaction. The EUGEI study

BACKGROUND

First-degree relatives of patients with psychotic disorder have higher levels of polygenic risk (PRS) for schizophrenia and higher levels of intermediate phenotypes.

METHODS

We conducted, using two different samples for discovery (n = 336 controls and 649 siblings of patients with psychotic disorder) and replication (n = 1208 controls and 1106 siblings), an analysis of association between PRS on the one hand and psychopathological and cognitive intermediate phenotypes of schizophrenia on the other in a sample at average genetic risk (healthy controls) and a sample at higher than average risk (healthy siblings of patients). Two subthreshold psychosis phenotypes, as well as a standardised measure of cognitive ability, based on a short version of the WAIS-III short form, were used. In addition, a measure of jumping to conclusion bias (replication sample only) was tested for association with PRS.

RESULTS

In both discovery and replication sample, evidence for an association between PRS and subthreshold psychosis phenotypes was observed in the relatives of patients, whereas in the controls no association was observed. Jumping to conclusion bias was similarly only associated with PRS in the sibling group. Cognitive ability was weakly negatively and non-significantly associated with PRS in both the sibling and the control group.

CONCLUSIONS

The degree of endophenotypic expression of schizophrenia polygenic risk depends on having a sibling with psychotic disorder, suggestive of underlying gene-environment interaction. Cognitive biases may better index genetic risk of disorder than traditional measures of neurocognition, which instead may reflect the population distribution of cognitive ability impacting the prognosis of psychotic disorder.

Misattributing speech and jumping to conclusions: A longitudinal study in people at high risk of psychosis

Biases in cognition such as Jumping to Conclusions (JTC) and Verbal Self-Monitoring (VSM) are thought to underlie the formation of psychotic symptoms. This prospective study in people with an At Risk Mental State (ARMS) for psychosis examined how these cognitive biases changed over time, and predicted clinical and functional outcomes. Twenty-three participants were assessed at clinical presentation and a mean of 31 months later. Performance on a JTC and VSM tasks were measured at both time points. Relationships to symptom severity, level of function and the incidence of psychotic disorder were then examined. The levels of symptoms, function and VSM all improved over time, while JTC was stable. Five participants (22%) developed a psychotic disorder during the follow-up period, but the risk of transition was not related to performance on either task at baseline, or to longitudinal changes in task performance. JTC performance correlated with symptom severity at baseline and follow-up. Similarly, performance on the two tasks was not related to the level of functioning at follow-up. Thus, while the ARMS is associated with both VSM and JTC biases, neither predict the onset of psychosis or the overall functional outcome.

Delusional ideation, manic symptomatology and working memory in a cohort at clinical high-risk for psychosis: A longitudinal study

We followed up a cohort (n = 35) of clients with an “At Risk Mental State” (ARMS) for almost 2 years (mean 21.3 months). At baseline, these clients had taken part in research looking at the relationship between reasoning biases, memory, personality styles and delusional ideation. During the follow-up period, clients underwent a package of intervention from a specialist early detection team. Eighty percent (n = 28) of these clients were successfully re-interviewed. There was improvement across the cohort as a whole, however five participants (17.9%) had made the transition to psychosis at follow-up. Those who had become psychotic had lower levels of manic symptomatology at baseline than those who did not enter the first episode. Further, across the cohort, impaired working memory and delusional ideation at baseline combined to predict 45% of the delusional ideation at follow-up. These preliminary findings suggest that working memory impairments may be linked to the persistence of delusional ideation and that manic symptoms in someone with an ARMS may suggest that such an individual is less likely to develop a frank psychotic episode.

Terminology and assessment tools of psychosis: A systematic narrative review

AIM

Phenomena within the psychosis continuum that varies in frequency/duration/intensity have been increasingly identified. Different terms describe these phenomena, however there is no standardization within the terminology. This review evaluated the definitions and assessment tools of seven terms - (i) 'psychotic experiences'; (ii) 'psychotic-like experiences'; (iii) 'psychotic-like symptoms'; (iv) 'attenuated psychotic symptoms'; (v) 'prodromal psychotic symptoms'; (vi) 'psychotic symptomatology'; and (vii) 'psychotic symptoms'.

METHODS

EMBASE, MEDLINE, and CINAHL were searched during February-March 2019. Inclusion criteria included 1989-2019, full text, human, and English. Papers with no explicit definition or assessment tool, duplicates, conference abstracts, systematic reviews, meta-analyses, or no access were excluded.

RESULTS

A total of 2238 papers were identified and of these, 627 were included. Definitions and assessment tools varied, but some trends were found. Psychotic experiences and psychotic-like experiences were transient and mild, found in the general population and those at-risk. Psychotic-like symptoms were subthreshold and among at-risk populations and non-psychotic mental disorders. Attenuated psychotic symptoms were subthreshold but associated with distress, risk, and help-seeking. Prodromal psychotic symptoms referred to the prodrome of psychotic disorders. Psychotic symptomatology included delusions and hallucinations within psychotic disorders. Psychotic symptoms was the broadest term, encompassing a range of populations but most commonly involving hallucinations, delusions, thought disorder, and disorganization.

DISCUSSION

A model for conceptualizing the required terms is proposed and future directions needed to advance this field of research are discussed.

The evolving sense of agency: Context recency and quality modulate the interaction between prospective and retrospective processes

Humans acquire a sense of agency through their interactions with the world and their sensory consequences. Previous studies have highlighted stable agency-related phenomena like intentional binding, which depend on both prospective, context-dependent and retrospective, outcome-dependent processes. In the current study, we investigated the interaction between prospective and retrospective processes underlying the adaptation of an ongoing sense of agency. The results showed that prospective intentional binding developed during a temporal window of up to 20 prior events was independent of the nature of the ongoing event. By contrast, the characteristics of the ongoing event retrospectively influenced prospective intentional binding developed during a temporal window narrower than 6 prior events. These findings characterize the interaction between prospective and retrospective mechanisms as a fundamental process to continuously update the sense of agency through sensorimotor learning. High psychosis-like experience traits weakened this interaction, suggesting that reduced adaption to the context contributes to altered self-experience.

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

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

Jumping to conclusions at first onset of psychosis predicts longer admissions, more compulsory admissions and police involvement over the next 4 years: the GAP study

BACKGROUND

Jumping to conclusions (JTC), which is the proneness to require less information before forming beliefs or making a decision, has been related to formation and maintenance of delusions. Using data from the National Institute of Health Research Biomedical Research Centre Genetics and Psychosis (GAP) case-control study of first-episode psychosis (FEP), we set out to test whether the presence of JTC would predict poor clinical outcome at 4 years.

METHODS

One-hundred and twenty-three FEP patients were assessed with the Positive and Negative Syndrome Scale (PANSS), Global Assessment of Functioning (GAF) and the probabilistic reasoning 'Beads' Task at the time of recruitment. The sample was split into two groups based on the presence of JTC bias. Follow-up data over an average of 4 years were obtained concerning clinical course and outcomes (remission, intervention of police, use of involuntary treatment - the Mental Health Act (MHA) - and inpatient days).

RESULTS

FEP who presented JTC at baseline were more likely during the follow-up period to be detained under the MHA [adjusted OR 15.62, 95% confidence interval (CI) 2.92-83.54, p = 0.001], require intervention by the police (adjusted OR 14.95, 95% CI 2.68-83.34, p = 0.002) and have longer admissions (adjusted IRR = 5.03, 95% CI 1.91-13.24, p = 0.001). These associations were not accounted for by socio-demographic variables, IQ and symptom dimensions.

CONCLUSIONS

JTC in FEP is associated with poorer outcome as indicated and defined by more compulsion police intervention and longer periods of admission. Our findings raise the question of whether the implementation of specific interventions to reduce JTC, such as Metacognition Training, may be a useful addition in early psychosis intervention programmes.

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.

Dopamine manipulations drive changes in information sampling in healthy volunteers

BACKGROUND

Information sampling is the cognitive process of accumulating information before committing to a decision. Patients across numerous disorders show decreased information sampling relative to controls.

AIMS

Here, we used the Beads and the Best Choice Tasks to study the role of dopamine signaling in information sampling.

METHODS

Participants were given placebo, amisulpride, or ropinirole in each session, in a double-blind cross-over design.

RESULTS

We found that ropinirole (agonist) increased the number of beads drawn in the Beads Task specifically when participants faced a loss, and decreased the rank of the chosen option in the Best Choice Task.

CONCLUSIONS

These effects are likely driven by a combination of effects at presynaptic D₂ receptors, which affect dopamine release, and post-synaptic D₂ receptors. Increased D₂ relative to D₁ receptor activation in the striatum leads to increased sampling in the loss condition in the Beads Task. It also leads to choice of a poorer ranked option in the Best Choice Task. Decreased D₂ relative to D₁ receptor activation leads to decreased sampling in the Beads Task in the loss condition.

The relationship between jumping to conclusions and neuropsychological functioning in schizophrenia

Jumping to conclusions (JTC) is defined as a tendency to make decisions based on insufficient information. JTC has been reported in patients with psychosis, but the mechanisms of this cognitive bias remain unknown. The main aim of our study was to investigate the relationship between JTC and neuropsychological functioning in schizophrenia. A total of 85 schizophrenia patients were assessed with neuropsychological tests, including executive functions, verbal memory, working memory, processing speed and attention. JTC was assessed with the Fish Task (probability 80:20 and 60:40) and a self-report scale (The Davos Assessment of Cognitive Biases Scale, DACOBS). Symptom severity was assessed with the Positive and Negative Syndrome Scale (PANSS). The relationship between JTC and neuropsychological functioning was investigated with correlation and regression analyses. The regression analyses model, when controlling for duration of illness, age and symptoms, showed that verbal memory and working memory were specifically related to JTC measured by Fish Task 60:40. JTC measured using Fish Task 60:40 was correlated only with severity of symptoms of disorganization (PANSS). The results from the present study suggest that the relationship between decision making during the reasoning task and neuropsychological functioning is modulated by task demands.

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

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

The Necessity of Ambiguity in Self-Other Processing: A Psychosocial Perspective With Implications for Mental Health

While distinguishing between the actions and physical boundaries of self and other (non-self) is usually straightforward there are contexts in which such differentiation is challenging. For example, self-other ambiguity may occur when actions of others are similar or complementary to those of the self. Even in the absence of such situational challenges, individuals experiencing hallucinations have difficulties with this distinction, often experiencing thoughts or actions of self as belonging to other agents. This paper explores the role of ambiguity in self-other differentiation, drawing from developmental, psychodynamic, and neurocognitive perspectives. A key proposal is that engagement in contexts that make distinctions between self and other challenging yet necessary allow reality-testing skills related to agency to develop. Attunement in typical caregiver-infant interactions is framed as a safe but inherently ambiguous environment that provides optimal condition for the infant to develop a coherent self-other sense. Vulnerability to psychosis may be related to limited access to such an environment in early development. However, the perceptual, cognitive, and social skills that contribution to attribution are likely to be malleable following infancy and improve though opportunities for boundary play in similarly ambiguous settings. Using music-making to illustrate, we postulate that engagement in intricate joint-actions that blurs agentic boundaries can contribute to the continued development of an adaptive sense of self and other essential to healthy social functioning. Increased insight into the self-other ambiguity may enhance our understanding of mechanisms underlying "self-disorders" such as schizophrenia and eventually extend the range of social and arts-based therapeutic possibilities.

Beta-Blocker Propranolol Modulates Decision Urgency During Sequential Information Gathering

Arbitrating between timely choice and extended information gathering is critical for effective decision making. Aberrant information gathering behavior is thought to be a feature of psychiatric disorders such as schizophrenia and obsessive-compulsive disorder, but we know little about the underlying neurocognitive control mechanisms. In a double-blind, placebo-controlled drug study involving 60 healthy human subjects (30 female), we examined the effects of noradrenaline and dopamine antagonism on information gathering during performance of an information sampling task. We show that modulating noradrenaline function with 40 mg of the β-blocker propranolol leads to decreased information gathering behavior. Modulating dopamine function via a single dose of 400 mg of amisulpride revealed some effects that were intermediate between those of propranolol and placebo. Using a Bayesian computational model, we show that sampling behavior is best explained by inclusion of a nonlinear urgency signal that promotes commitment to an early decision. Noradrenaline blockade promotes the expression of this decision-related urgency signal during information gathering. We discuss the findings with respect to psychopathological conditions that are linked to aberrant information gathering.SIGNIFICANCE STATEMENT Knowing when to stop gathering information and commit to a choice option is nontrivial. This is an important element in arbitrating between information gain and energy conservation. In this double-blind, placebo-controlled drug study, we investigated the role of catecholamines noradrenaline and dopamine on sequential information gathering. We found that blockade of noradrenaline led to a decrease in information gathering. Dopamine blockade showed an intermediate, but nonsignificant, effect. Using a Bayesian computational model, we show that this noradrenaline effect is driven by increased decision urgency, a signal that reflects an escalating subjective cost of sampling. The observation that noradrenaline modulates decision urgency suggests new avenues for treating patients that show information gathering deficits.

Neuropsychological functioning and jumping to conclusions in recent onset psychosis patients

BACKGROUND

The reasoning bias of jumping to conclusions (JTC) consists of a tendency to make assumptions having little information.

OBJECTIVE

The aim of this study was to estimate the differences in neuropsychological functioning between recent onset psychotic patients who jump to conclusions and those who do not jump to conclusions.

MATERIALS AND METHODS

One hundred and twenty-two patients with a recent onset of a psychotic disorder were assessed with three JTC tasks and a neuropsychological battery exploring verbal learning, memory, attention, psychomotor speed, visuoperceptual abilities, working memory, problem solving, executive functioning.

RESULTS

A total of 29.7% (n=36) of the individuals jumped to conclusions in Task 1, 14.0% (n=17) in Task 2, and 15.7% (n=19) in Task 3. People who jump to conclusions in three tasks scored significantly worse in many neuropsychological domain deficits, including attention (p<0.001-0.020), psychomotor speed (p<0.001), working memory (p<0.001-0.040), and executive functioning (p<0.001-0.042).

DISCUSSION

The present study demonstrates that JTC is present even in early stages of the illness, and that there is a relationship between JTC and neuropsychological functioning.

Helping patients with paranoid and suspicious thoughts: a cognitive–behavioural approach

Paranoid and suspicious thoughts are a significant clinical topic. They regularly occur in 10–15% of the general population, and persecutory delusions are a frequent symptom of psychosis. In the past, patients were discouraged from talking about paranoid experiences. In contrast, it is now recommended that patients are given time to talk about them, and cognitive–behavioural techniques are being used to reduce distress. In this article we present the theoretical understanding of paranoia that underpins this transformation in the treatment of paranoid thoughts and summarise the therapeutic techniques derived. Emphasis is placed on the clinician approaching the problem from a perspective of understanding and making sense of paranoid experiences rather than simply challenging paranoid thoughts. Ways of overcoming difficulties in engaging people with paranoid thoughts are highlighted.

Intranasal oxytocin does not modulate jumping to conclusions in schizophrenia: Potential interactions with caudate volume and baseline social functioning

BACKGROUND

Patients with schizophrenia (SCZ) tend to sample less information when making a decision, jumping to conclusions (JTC) without sufficient evidence. This "JTC bias" may be a trait marker of the disease and may not improve with antipsychotic treatment. We conducted a double-blind, placebo-controlled trial to test whether intranasal oxytocin could reduce JTC in stable, medicated patients with SCZ and healthy controls (HCs). We also explored whether striatal volume, clinical symptoms, and baseline social functioning (SF) was related to JTC performance.

METHODS

Forty-three male, medicated SCZ patients (Mean Age: 40.81±11.44) and sixteen HCs (Mean Age: 30.38±9.85) participated in a double-blind, placebo-controlled, cross-over study. Participants completed the Beads Task on two separate visits (minimum 20days apart). Participants were randomized to receive either intranasal oxytocin (50IU in solution) or intranasal placebo (saline). Twenty of the SCZ patients and all sixteen HCs also provided T1 MRIs (3-T).

RESULTS

Patients with SCZ took fewer draws to decision (DTD) than HCs (t(57)=2.78, p=0.007). Oxytocin did not significantly change DTD in patients (t(42)=-1.11, p=0.27), nor in HCs (t(15)=-0.62, p=0.55). Exploratory analyses found ventral caudate volumes were negatively correlated with DTD (r(18)=-0.50, p=0.03) in patients. Moreover, oxytocin was more likely to improve JTC in patients with lower baseline SF. However, these exploratory findings did not survive correction for multiple comparisons.

CONCLUSIONS

We replicate increased JTC in SCZ. However, acute intranasal oxytocin did not modify JTC. Future studies with larger samples should explore how brain morphology and SF are related to JTC performance in patients with SCZ.

[Delusions: current psychodynamic and neurocognitive approaches]

BACKGROUND

The symptom "delusions" is a central psychopathological symptom in psychiatric diseases. Since the beginning of psychiatry various disciplines have attempted to explain and understand delusions but even now no generally accepted definition of this phenomenon exists.

AIM

A comprehensive review of current psychopathological and neurobiological theories of delusions is given.

MATERIAL AND METHODS

PubMed and Google scholar searches were performed using the keywords "delusion", "psychodynamic" and "neurobiology", both in English and German. Relevant German textbooks of psychiatry were also included.

DISCUSSION

A differentiated perspective of the phenomenon of delusions appears to be necessary to approach this complex and fascinating symptom. A one-dimensional approach does not do justice to the complexity of delusions. The various explanatory approaches can increasingly be linked to each other and are no longer considered to be mutually exclusive.

Psychotic Experiences and Overhasty Inferences Are Related to Maladaptive Learning

Theoretical accounts suggest that an alteration in the brain’s learning mechanisms might lead to overhasty inferences, resulting in psychotic symptoms. Here, we sought to elucidate the suggested link between maladaptive learning and psychosis. Ninety-eight healthy individuals with varying degrees of delusional ideation and hallucinatory experiences performed a probabilistic reasoning task that allowed us to quantify overhasty inferences. Replicating previous results, we found a relationship between psychotic experiences and overhasty inferences during probabilistic reasoning. Computational modelling revealed that the behavioral data was best explained by a novel computational learning model that formalizes the adaptiveness of learning by a non-linear distortion of prediction error processing, where an increased non-linearity implies a growing resilience against learning from surprising and thus unreliable information (large prediction errors). Most importantly, a decreased adaptiveness of learning predicted delusional ideation and hallucinatory experiences. Our current findings provide a formal description of the computational mechanisms underlying overhasty inferences, thereby empirically substantiating theories that link psychosis to maladaptive learning.

Predictive coding theories represent a unifying account of psychosis, stating that the central psychosis-related alteration affects the interplay between prior predictions and incoming information. Since every incoming information is imprecise and potentially allows for different interpretations, prior expectations achieve the enforcement of interpretations with a higher prior probability. Disturbances in this basic framework might let unlikely interpretations come into effect, resulting in proneness for delusions and hallucinations. Here, we contribute to these theories by devising a novel computational model for behavior in a reasoning task that quantifies the participants' readiness to draw inferences from very surprising information. We thereby demonstrate that precisely this increased learning from surprising and thus potentially spurious information, as opposed to non-specific alterations in the general learning speed, predispose healthy individuals for delusions and hallucinations. The present results hence speak for the hypothesis that hallucinations and delusions arise when noisy information is considered as precise and is thus not suppressed by opposing prior beliefs. In this sense, our findings also tie with recent neurophysiological models of psychosis that posit aberrations in modulatory neurotransmitters such as dopamine (or its interactions with GABAergic interneurons) as a correlate of perturbed computations of information precision in the cortex.

The involvement of the striatum in decision making

Decision making has been extensively studied in the context of economics and from a group perspective, but still little is known on individual decision making. Here we discuss the different cognitive processes involved in decision making and its associated neural substrates. The putative conductors in decision making appear to be the prefrontal cortex and the striatum. Impaired decision-making skills in various clinical populations have been associated with activity in the prefrontal cortex and in the striatum. We highlight the importance of strengthening the degree of integration of both cognitive and neural substrates in order to further our understanding of decision-making skills. In terms of cognitive paradigms, there is a need to improve the ecological value of experimental tasks that assess decision making in various contexts and with rewards; this would help translate laboratory learnings into real-life benefits. In terms of neural substrates, the use of neuroimaging techniques helps characterize the neural networks associated with decision making; more recently, ways to modulate brain activity, such as in the prefrontal cortex and connected regions (eg, striatum), with noninvasive brain stimulation have also shed light on the neural and cognitive substrates of decision making. Together, these cognitive and neural approaches might be useful for patients with impaired decision-making skills. The drive behind this line of work is that decision-making abilities underlie important aspects of wellness, health, security, and financial and social choices in our daily lives.

Synthetic Cannabinoid Use in a Psychiatric Patient Population: A Pilot Study

BACKGROUND

Consumption of natural cannabis (NC) and synthetic cannabinoids (SCs) has been associated with psychotic disorders. We compared the prevalence of use, consumer profiles, and psychosis-inducing potential of NC and SCs in a specific high-risk population.

METHODS

This prospective pilot study included 332 patients (18-64 years, mean 36.83, SD 13.33). Patients' sociodemographics and medical histories as well as illicit substance use and psychiatric symptom histories were collected using a drug consumption survey that assessed the use of new psychoactive substances and the Psychotic Symptoms Interview.

RESULTS

In total, 7.2% of all patients, 10.6% of psychotic patients, and 4.5% of nonpsychotic patients reported SC consumption. Compared with SCs, NC was consumed much more frequently by its users (mean 222.73, SD 498.27). NC and SC use induced persistent psychosis. Psychotic symptoms were first experienced by patients with a history of NC or SC use during intoxication and persisted after cessation (>1 year) of drug use. Positive and negative symptoms tended to be more severe in SC and NC users, respectively.

CONCLUSIONS

NC and SCs may cause different symptom clusters. These relationships should be further evaluated.

Reasoning in psychosis: risky but not necessarily hasty

INTRODUCTION

A liberal acceptance (LA) threshold for hypotheses has been put forward to explain the well-replicated "jumping to conclusions" (JTC) bias in psychosis, particularly in patients with paranoid symptoms. According to this account, schizophrenia patients rest their decisions on lower subjective probability estimates. The initial formulation of the LA account also predicts an absence of the JTC bias under high task ambiguity (i.e., if more than one response option surpasses the subjective acceptance threshold).

METHODS

Schizophrenia patients (n = 62) with current or former delusions and healthy controls (n = 30) were compared on six scenarios of a variant of the beads task paradigm. Decision-making was assessed under low and high task ambiguity. Along with decision judgments (optional), participants were required to provide probability estimates for each option in order to determine decision thresholds (i.e., the probability the individual deems sufficient for a decision).

RESULTS

In line with the LA account, schizophrenia patients showed a lowered decision threshold compared to controls (82% vs. 93%) which predicted both more errors and less draws to decisions. Group differences on thresholds were comparable across conditions. At the same time, patients did not show hasty decision-making, reflecting overall lowered probability estimates in patients.

CONCLUSIONS

Results confirm core predictions derived from the LA account. Our results may (partly) explain why hasty decision-making is sometimes aggravated and sometimes abolished in psychosis. The proneness to make risky decisions may contribute to the pathogenesis of psychosis. A revised LA account is put forward.

Who "jumps to conclusions"? A comprehensive assessment of probabilistic reasoning in psychosis following traumatic brain injury (PFTBI), and comparison with TBI, schizophrenia, and nonclinical controls

INTRODUCTION

The "jumping to conclusions" (JTC) bias has received significant attention in the schizophrenia and delusion literature as an important aspect of cognition characterising psychosis. The JTC bias has not been explored in psychosis following traumatic brain injury (PFTBI).

METHODS

JTC was investigated in 10 patients with PFTBI using the beads task (ratios 85:15 and 60:40). Probabilistic predictions, draws-to-decision, self-rated decision confidence, and JTC bias were recorded. Responses from 10 patients with traumatic brain injury (TBI), 23 patients with schizophrenia, and 23 nonclinical controls were compared. Relationships were explored between draws-to-decision and current intelligence quotient, affective state, executive function, delusions (severity and type), and illness chronicity (duration).

RESULTS

Groups were comparable on JTC measures. Delusion severity and type were not related to draws-to-decision for either trial. In the entire sample, executive function (reduced mental flexibility) was significantly related to more draws-to-decision on the 60:40 ratio trial.

CONCLUSIONS

We found no evidence for an elevated JTC bias in patients with PFTBI or TBI alone. The influence of executive dysfunction should be considered by future studies using the beads tasks in patient populations. These findings need to be replicated in larger PFTBI and TBI samples.

Evaluation of the 'Jumping to conclusions' bias in different subgroups of the at-risk mental state: from cognitive basic symptoms to UHR criteria

BACKGROUND

Patients with psychosis display the so-called 'Jumping to Conclusions' bias (JTC) - a tendency for hasty decision-making in probabilistic reasoning tasks. So far, only a few studies have evaluated the JTC bias in 'at-risk mental state' (ARMS) patients, specifically in ARMS samples fulfilling 'ultra-high risk' (UHR) criteria, thus not allowing for comparisons between different ARMS subgroups.

METHOD

In the framework of the PREVENT (secondary prevention of schizophrenia) study, a JTC task was applied to 188 patients either fulfilling UHR criteria or presenting with cognitive basic symptoms (BS). Similar data were available for 30 healthy control participants matched for age, gender, education and premorbid verbal intelligence. ARMS patients were identified by the Structured Interview for Prodromal Symptoms (SIPS) and the Schizophrenia Proneness Instrument - Adult Version (SPI-A).

RESULTS

The mean number of draws to decision (DTD) significantly differed between ARM -subgroups: UHR patients made significantly less draws to make a decision than ARMS patients with only cognitive BS. Furthermore, UHR patients tended to fulfil behavioural criteria for JTC more often than BS patients. In a secondary analysis, ARMS patients were much hastier in their decision-making than controls. In patients, DTD was moderately associated with positive and negative symptoms as well as disorganization and excitement.

CONCLUSIONS

Our data indicate an enhanced JTC bias in the UHR group compared to ARMS patients with only cognitive BS. This underscores the importance of reasoning deficits within cognitive theories of the developing psychosis. Interactions with the liability to psychotic transitions and therapeutic interventions should be unravelled in longitudinal studies.

The prevalence of visual hallucinations in non-affective psychosis, and the role of perception and attention

BACKGROUND

Little is known about visual hallucinations (VH) in psychosis. We investigated the prevalence and the role of bottom-up and top-down processing in VH. The prevailing view is that VH are probably related to altered top-down processing, rather than to distorted bottom-up processing. Conversely, VH in Parkinson's disease are associated with impaired visual perception and attention, as proposed by the Perception and Attention Deficit (PAD) model. Auditory hallucinations (AH) in psychosis, however, are thought to be related to increased attention.

METHOD

Our retrospective database study included 1119 patients with non-affective psychosis and 586 controls. The Community Assessment of Psychic Experiences established the VH rate. Scores on visual perception tests [Degraded Facial Affect Recognition (DFAR), Benton Facial Recognition Task] and attention tests [Response Set-shifting Task, Continuous Performance Test-HQ (CPT-HQ)] were compared between 75 VH patients, 706 non-VH patients and 485 non-VH controls.

RESULTS

The lifetime VH rate was 37%. The patient groups performed similarly on cognitive tasks; both groups showed worse perception (DFAR) than controls. Non-VH patients showed worse attention (CPT-HQ) than controls, whereas VH patients did not perform differently.

CONCLUSIONS

We did not find significant VH-related impairments in bottom-up processing or direct top-down alterations. However, the results suggest a relatively spared attentional performance in VH patients, whereas face perception and processing speed were equally impaired in both patient groups relative to controls. This would match better with the increased attention hypothesis than with the PAD model. Our finding that VH frequently co-occur with AH may support an increased attention-induced 'hallucination proneness'.

Psychosis as a transdiagnostic and extended phenotype in the general population

A large body of research indicates that weak expressions of positive psychotic symptoms ("psychotic experiences") can be measured in the general population, and likely represent the behavioural manifestation of distributed multifactorial (genetic and non-genetic) risk for psychosis. Psychotic experiences are a transdiagnostic phenomenon: the majority of individuals with these experiences have a diagnosis of non-psychotic disorder, particularly common mental disorder, in which psychotic experiences predict greater illness severity and poorer treatment response. Some of the people with common mental disorder and psychotic experiences will present to mental health services meeting criteria for "clinical high risk". Treatment of the transdiagnostic dimension of psychosis in individuals with common mental disorder who meet "clinical high risk" criteria thus may improve outcome (which cannot be interpreted as prevention of "schizophrenia"). Subthreshold psychotic experiences are transitory in about 80% of individuals, while around 20% go on to develop persistent psychotic experiences and 7% a psychotic disorder, with an annual transition rate of 0.5-1%. Persistence is associated, on the one hand, with environmental exposures, particularly childhood trauma, and, on the other, with network-type dynamic interactions between psychotic experiences themselves (e.g., interactions between hallucinatory experiences and delusional ideation) and between symptom dimensions (e.g., interactions between affective symptoms and psychotic experiences, or interactions between subthreshold negative symptoms and psychotic experiences). The study of psychotic experiences is helping to elucidate the mechanisms by which environmental and genetic influences shape the transdiagnostic expression of psychosis proneness, that is mostly transitory but may first become persistent over time and eventually give rise to transition to a psychotic disorder.

Counterfactual Reasoning in Non-psychotic First-Degree Relatives of People with Schizophrenia

Counterfactual thinking (CFT) is a type of conditional reasoning that enables the generation of mental simulations of alternatives to past factual events. Previous research has found this cognitive feature to be disrupted in schizophrenia (Hooker et al., 2000; Contreras et al., 2016). At the same time, the study of cognitive deficits in unaffected relatives of people with schizophrenia has significantly increased, supporting its potential endophenotypic role in this disorder. Using an exploratory approach, the current study examined CFT for the first time in a sample of non-psychotic first-degree relatives of schizophrenia patients (N = 43), in comparison with schizophrenia patients (N = 54) and healthy controls (N = 44). A series of tests that assessed the "causal order effect" in CFT and the ability to generate counterfactual thoughts and counterfactually derive inferences using the Counterfactual Inference Test was completed. Associations with variables of basic and social cognition, levels of schizotypy and psychotic-like experiences in addition to clinical and socio-demographic characteristics were also explored. Findings showed that first-degree relatives generated a lower number of counterfactual thoughts than controls, and were more adept at counterfactually deriving inferences, specifically in the scenarios related to regret and to judgments of avoidance in an unusual situation. No other significant results were found. These preliminary findings suggest that non-psychotic first-degree relatives of schizophrenia patients show a subtle disruption of global counterfactual thinking compared with what is normally expected in the general population. Due to the potential impact of such deficits, new treatments targeting CFT improvement might be considered in future management strategies.

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

We did a systematic review and meta-analysis to investigate the magnitude and specificity of the "jumping to conclusions" (JTC) bias in psychosis and delusions. We examined the extent to which people with psychosis, and people with delusions specifically, required less information before making decisions. We examined (1) the average amount of information required to make a decision and (2) numbers who demonstrated an extreme JTC bias, as assessed by the "beads task." We compared people with psychosis to people with and without nonpsychotic mental health problems, and people with psychosis with and without delusions. We examined whether reduced data-gathering was associated with increased delusion severity. We identified 55 relevant studies, and acquired previously unpublished data from 16 authors. People with psychosis required significantly less information to make decisions than healthy individuals (k= 33,N= 1935,g= -0.53, 95% CI -0.69, -0.36) and those with nonpsychotic mental health problems (k= 13,N= 667,g= -0.58, 95% CI -0.80, -0.35). The odds of extreme responding in psychosis were between 4 and 6 times higher than the odds of extreme responding by healthy participants and participants with nonpsychotic mental health problems. The JTC bias was linked to a greater probability of delusion occurrence in psychosis (k= 14,N= 770, OR 1.52, 95% CI 1.12, 2.05). There was a trend-level inverse association between data-gathering and delusion severity (k= 18;N= 794;r= -.09, 95% CI -0.21, 0.03). Hence, nonaffective psychosis is characterized by a hasty decision-making style, which is linked to an increased probability of delusions.

Metacognitive training for schizophrenia spectrum patients: a meta-analysis on outcome studies

BACKGROUND

Metacognitive training (MCT) for schizophrenia spectrum is widely implemented. It is timely to systematically review the literature and to conduct a meta-analysis.

METHOD

Eligible studies were selected from several sources (databases and expert suggestions). Criteria included comparative studies with a MCT condition measuring positive symptoms and/or delusions and/or data-gathering bias. Three meta-analyses were conducted on data gathering (three studies; 219 participants), delusions (seven studies; 500 participants) and positive symptoms (nine studies; 436 participants). Hedges' g is reported as the effect size of interest. Statistical power was sufficient to detect small to moderate effects.

RESULTS

All analyses yielded small non-significant effect sizes (0.26 for positive symptoms; 0.22 for delusions; 0.31 for data-gathering bias). Corrections for publication bias further reduced the effect sizes to 0.21 for positive symptoms and to 0.03 for delusions. In blinded studies, the corrected effect sizes were 0.22 for positive symptoms and 0.03 for delusions. In studies using proper intention-to-treat statistics the effect sizes were 0.10 for positive symptoms and -0.02 for delusions. The moderate to high heterogeneity in most analyses suggests that processes other than MCT alone have an impact on the results.

CONCLUSIONS

The studies so far do not support a positive effect for MCT on positive symptoms, delusions and data gathering. The methodology of most studies was poor and sensitivity analyses to control for methodological flaws reduced the effect sizes considerably. More rigorous research would be helpful in order to create enough statistical power to detect small effect sizes and to reduce heterogeneity. Limitations and strengths are discussed.

Factors contributing to social cognition impairment in borderline personality disorder and schizophrenia

Social cognition (SC) deficits have been described both in patients with schizophrenia and borderline personality disorder (BPD). However, while the former tend towards simplistic mental state attributions (undermentalizing), the latter are more likely to make overly complex mental state inferences (overmentalizing). Performance on complex SC tasks has been shown to correlate with neurocognitive ability, emotion perception, a history of trauma, and overconfidence in errors. However, it is unclear how these factors relate to different aspects of SC deficits. Aim of the present study was to examine the pathways of SC impairment by investigating performance profiles and their predictors comparatively in BPD and schizophrenia. Participants were 44 patients with BPD, 36 patients with schizophrenia, and 38 healthy controls. Undermentalizing and overmentalizing were assessed with an ecologically valid SC task. Patients with BPD exhibited increased overmentalizing, whereas patients with schizophrenia showed a more extensive deficit pattern, their main error type being undermentalizing. Overconfidence in errors was the most important predictor for overmentalizing, while undermentalizing depended mainly on verbal memory and emotion perception. Thus, BPD und schizophrenia exhibited different SC impairment patterns, and different types of SC errors were predicted by different factors. These findings have implications for the optimization of treatment approaches.

A comparison of cognitive biases between schizophrenia patients with delusions and healthy individuals with delusion-like experiences

BACKGROUND

The role of psychosis-related cognitive biases (e.g. jumping to conclusions) in a delusion continuum is well-established. Little is known about the role of types of cognitive biases. The aim of this study was to investigate the role of psychosis-related and "Beckian" (i.e. anxiety- and depression-related) cognitive biases assessed with a clinical questionnaire in the delusion continuum and its dimensions.

METHODS

Schizophrenia patients with (n=57) and without (n=35) delusions were compared to healthy subjects who had a low (n=53) and high (n=57) level of delusion-like experiences (DLEs) on the Cognitive Biases Questionnaire for Psychosis (CBQp). Delusion dimensions in the clinical sample were assessed with the semi-structured interview PSYRATS. DLEs were measured with the Peters Delusion Inventory (PDI).

RESULTS

High DLEs participants scored significantly higher than low DLEs, and patients with delusions scored higher than patients without delusions on the total scores of the CBQp. High DLEs participants scored significantly higher than low DLEs on catastrophisation and JTC. Schizophrenia patients with delusions scored significantly higher when compared to patients without delusions on intentionalising, dichotomous thinking, JTC and emotional reasoning. Patients with delusions and high DLEs participants scored similarly on JTC. Stepwise regression analysis revealed that catastrophising predicted total severity of clinical delusions and JTC predicted the cognitive dimension of clinical delusions. Both JTC and catastrophisation predicted the frequency and conviction associated with DLEs.

CONCLUSIONS

Both "Beckian" and psychosis-related cognitive biases may underlie delusions. Different aspects of clinical delusions and delusion-like experiences may be related to different cognitive biases.