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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

A randomized controlled feasibility trial of metacognitive training with adolescents receiving treatment for anorexia nervosa

OBJECTIVE

This pilot study investigated the feasibility and preliminary efficacy of the metacognitive training for eating disorders (MCT-ED) program in adolescents with anorexia nervosa (AN). We report attrition and subjective evaluation as well as changes to cognitive flexibility, perfectionism and eating disorder pathology relative to waitlist controls.

METHOD

Female (n = 35, aged 13-17 years) outpatients with a diagnosis of AN (n = 20) or atypical AN (n = 15) completed baseline measures of cognitive flexibility, perfectionism, and eating disorder pathology (May 2020-May 2022). Participants were randomly allocated to either treatment-as-usual (TAU) plus MCT-ED or TAU waitlist condition. All participants completed post-intervention and 3-month follow-up questionnaires.

RESULTS

The MCT-ED condition had a treatment attrition rate <15%. Participants provided positive evaluation of the program. There were large between groups differences favoring MCT-ED at post-intervention and 3-month follow-up for concern over mistakes perfectionism (respective ds = -1.25, 95% CI [-2.06, -.45]; -.83, 95% CI [-1.60, .06]) with a significant group difference post-intervention but not 3-month follow-up.

DISCUSSION

Findings provide tentative support for the feasibility of MCT-ED as an adjunct intervention for young people with AN, however replication is needed with a larger sample size to further explore its efficacy.

PUBLIC SIGNIFICANCE

Metacognitive training for eating disorders (MCT-ED) is a feasible adjunct intervention for adolescents with anorexia nervosa. The intervention, which targets thinking styles and is delivered online by a therapist, received positive feedback, had high treatment retention, and led to reductions in perfectionism by the end of treatment compared to wait-list controls. Although these gains were not sustained long-term, the program is suitable adjunct intervention for young people with eating disorders.

Hasty decision-making in individuals at higher risk of developing an eating disorder

BACKGROUND AND OBJECTIVES

The Jumping to Conclusions (JTC) bias is the tendency to make hasty decisions based on limited evidence and may contribute to the formation of over-valued beliefs about the importance of weight, shape and eating. Previous research investigating the JTC bias in clinical eating disorder samples, as assessed by the beads task, is inconclusive. The current study investigated the JTC bias in a non-clinical sample of undergraduate students identified as being lower or higher risk of developing an eating disorder. The study used a more reliable 'distractor' beads task that also incentivised hastier decisions by elevating the pressure of the task.

METHODS

Female undergraduate students (N = 156, 48%, classified as higher risk) completed a pressure and non-pressure distractor beads task, along with measures of weight concern and body-image flexibility.

RESULTS

Higher risk participants displayed a hastier decision-making style than lower risk participants. Task pressure elicited a hastier decision-making style across the whole sample, however, was unable to distinguish between higher and lower eating disorder risk status.

LIMITATIONS

Interpretation of findings are limited to non-clinical samples and may not generalise to clinical eating disorder populations.

CONCLUSIONS

Findings suggest the need for replication in a clinical eating disorder sample using the distractor beads task. Future research should investigate whether eating disorder salient stimuli elicits a stronger bias.

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.

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.

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

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

How Do Delusion-Prone Individuals Respond to Disconfirmatory Evidence?

Abstract. Research employing the beads task suggests that people with delusional tendencies over-adjust to disconfirmatory evidence compared to low-delusion-prone individuals. This interpretation is in tension with studies using the bias against disconfirmatory evidence (BADE) task, which provide evidence that people with delusional tendencies are less receptive to disconfirmatory evidence. It has been suggested that over-adjustment on the beads task may be driven by miscomprehension of the task. The current preliminary study aimed to minimize miscomprehension on the beads task and determine how high-delusion-prone people respond to disconfirmatory evidence on both tasks. Fifty-one undergraduate participants completed the BADE task and an adapted version of the beads task. We expected that corrective feedback on the beads task would reduce miscomprehension, and that high-delusion-prone participants would be less receptive to disconfirmatory evidence on both tasks. Our results suggest this version of the beads task improved rates of comprehension relative to previous research. However, we found no evidence that the high-delusion-prone group demonstrated elevated over-adjustment or belief inflexibility in either task. The theoretical implications of these findings are discussed.

Towards a reliable repeated-measures beads task for assessing the jumping to conclusions bias

The jumping to conclusions bias (JTC), in which some people gather less information than others before making a decision, has been linked to delusions in psychosis. JTC is usually identified via the beads task, in which a sequence of beads (the "target" sequence) is used to measure the amount of evidence participants require before making a decision. Yet, despite its common use, the reliability of the task has never been properly investigated. We investigated its reliability, and tested an alternate version which used distractor sequences to obfuscate the target sequence. Healthy participants (N = 212) were randomised into two groups. One group completed ten trials using the target sequence, while the other completed ten trials of the target sequence and three distractor sequences. Our data indicated the standard task may not be reliable over repeated measures, but that by including distractor sequences, the task becomes more believable, repeatable, and reliable. Additionally, excluding first-trial data (a "silent" practice trial) also improves repeatability. These improvements to the task are relevant to single trial studies, and will be especially useful to repeated-measures longitudinal, experimental, and treatment studies. Such repeated-measures studies are important for investigating the causal link between JTC and delusions.

Shorter telomere length in people with schizophrenia: A preliminary study from Australia

Schizophrenia is a complex mental illness affecting the normal functioning of the brain, interfering with the ability to think, feel and act. It can be conceptualised as a syndrome of accelerated ageing, with early onset of cardiovascular disease and high rates of premature mortality. Telomere attrition increases with oxidative stress and is considered a biomarker of ageing. Previous studies have assessed abnormalities in telomere length in schizophrenia, but the results are inconsistent. The present study used a case-control design to assess whether people with schizophrenia have shortened telomeres, indicative of accelerated ageing. Subjects were all male, aged 25-35years, living in the same urban region of Adelaide, South Australia. Telomere length was measured using a quantitative real-time polymerase chain reaction (PCR) method. We found significantly shorter telomeres in people with schizophrenia relative to healthy controls. This is the first study to show telomere attrition among people with schizophrenia in Australia. Shorter telomere length may indicate the common pathways that schizophrenia shares with other neuropsychiatric and neurodevelopmental disorders associated with increased cellular senescence. Further well-controlled larger studies in people with schizophrenia are required to fully understand (i) the role of variables that have the potential to modulate telomere length such as use of antipsychotic drugs, medical conditions, parental age, smoking, alcohol abuse and use of illicit drugs; (ii) effective treatments to slow telomere erosion and (iii) mechanisms responsible for accelerating and reducing telomere damage.

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

BACKGROUND AND OBJECTIVES

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

RESULTS

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

LIMITATIONS

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

CONCLUSION

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

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

OBJECTIVES

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

METHODS

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

HYPOTHESIS

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

LIMITATIONS

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

CONCLUSIONS

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

Dopamine, cognitive biases and assessment of certainty: A neurocognitive model of delusions

This paper examines the evidence that delusions can be explained within the framework of a neurocognitive model of how the brain assesses certainty. Here, 'certainty' refers to both low-level interpretations of one's environment and high-level (conscious) appraisals of one's beliefs and experiences. A model is proposed explaining how the brain systems responsible for assigning certainty might dysfunction, contributing to the cause and maintenance of delusional beliefs. It is suggested that delusions arise through a combination of perturbed striatal dopamine and aberrant salience as well as cognitive biases such as the tendency to jump to conclusions (JTC) and hypersalience of evidence-hypothesis matches. The role of emotion, stress, trauma and sociocultural factors in forming and modifying delusions is also considered. Understanding the mechanisms involved in forming and maintaining delusions has important clinical implications, as interventions that improve cognitive flexibility (e.g. cognitive remediation therapy and mindfulness training) could potentially attenuate neurocognitive processes.

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

We completed a meta-analysis to investigate the relationship between delusions in psychosis and 4 cognitive biases: "jumping to conclusions" (JTC), the "bias against disconfirmatory evidence" (BADE), the "bias against confirmatory evidence" (BACE), and "liberal acceptance" (LA). Building on recent meta-analyses we compared more narrowly defined groups. We identified 35 JTC, 8 BADE, 7 BACE, and 6 LA studies for inclusion. Groups with schizophrenia who were currently experiencing delusions demonstrated greater JTC, BADE, BACE, and LA than groups with schizophrenia who were not currently experiencing delusions, who in turn demonstrated no more JTC than healthy control groups. Hence JTC, BADE, BACE, and LA co-vary with delusions in cross-sectional samples of people with schizophrenia. Groups who were experiencing delusions due to other psychiatric illnesses also demonstrated greater JTC than healthy controls, and equivalent JTC to groups with schizophrenia currently experiencing delusions. Hence JTC is associated with delusions across a range of diagnoses. Groups with other, non-delusional psychiatric illnesses demonstrated less JTC, BADE, BACE, and LA than groups with schizophrenia currently experiencing delusions, less JTC than groups experiencing delusions due to other diagnoses, and no more JTC, BADE, BACE, or LA than healthy control groups. Hence JTC, BADE, BACE, and LA were not associated with psychiatric illnesses in general. Our results indicate all 4 biases are associated with delusions specifically rather than merely with a diagnosis of schizophrenia or with being psychiatrically ill, consistent with the possibility that they contribute to delusional severity.

Subjective versus objective cognition: Evidence for poor metacognitive monitoring in schizophrenia

BACKGROUND

Patients with schizophrenia display a number of cognitive biases, particularly a tendency to jump to conclusions, which are implicated in the pathogenesis of the disorder. The present study contrasted the degree of objective reasoning biases with subjective cognitive insight. We expected that patients with schizophrenia would display greater objective than subjective impairment suggestive of poor metacognitive awareness.

METHODS

Patients with schizophrenia (n=140) and healthy controls (n=60) underwent a test battery encompassing a cognitive bias paradigm (beads task) as well as neurocognitive tests (story recall, trail-making tests). In addition, they were administered the Beck Cognitive Insight Scale (BCIS), a subjective measure of (meta)cognitive awareness.

RESULTS

Corroborating prior research on decision making, draws to decisions were significantly delayed in controls relative to patients, whereas the core jumping to conclusion parameter (i.e., decision after one or two pieces of information) bordered significance. Patients with schizophrenia showed a lowered decision threshold and impaired neurocognition relative to nonclinical controls. Despite poor cognitive performance and prior psychotic episodes, patients with schizophrenia showed similar scores on the self-confidence subscale of the BCIS and reported even higher levels of self-reflectiveness relative to healthy controls.

DISCUSSION

The study demonstrates that patients with schizophrenia show severe cognitive biases and neurocognitive deficits but display only partial awareness herein. Raising cognitive insight in a non-insulting fashion and elevating patients' corrigibility as well as willingness to consider others' feedback and advice may help to narrow this gap and improve psychiatric symptomatology.

An investigation into the jumping-to-conclusions bias in social anxiety

'Jumping-to-Conclusions' (JTC) is a data-gathering bias characterised by hasty decision-making, and is typically seen in individuals with high levels of delusions or paranoia. JTC has also been found in people with high trait and state anxiety. The present study aimed to explore the relationship between JTC and trait social anxiety and state anxiety, given paranoia is common in both social anxiety and psychotic disorders. One-hundred-and-eighty-six undergraduate students were allocated to a manipulation or control condition, and classified as high or low socially anxious. All participants completed the 'beads task' to assess JTC, and the State-Trait Anxiety Inventory (state subscale) to assess state anxiety. Participants in the manipulation condition were given an anxiety-inducing situation. Although the manipulation was effective in inducing state anxiety, there was no significant correlation between JTC and trait or state social anxiety. High socially anxious individuals showed more conservative decision-making than controls over time, which was posited to be caused by inhibited working memory resulting from increased state anxiety.

Overconfidence across the psychosis continuum: a calibration approach

INTRODUCTION

An 'overconfidence in errors' bias has been consistently observed in people with schizophrenia relative to healthy controls, however, the bias is seldom found to be associated with delusional ideation. Using a more precise confidence-accuracy calibration measure of overconfidence, the present study aimed to explore whether the overconfidence bias is greater in people with higher delusional ideation.

METHODS

A sample of 25 participants with schizophrenia and 50 non-clinical controls (25 high- and 25 low-delusion-prone) completed 30 difficult trivia questions (accuracy <75%); 15 'half-scale' items required participants to indicate their level of confidence for accuracy, and the remaining 'confidence-range' items asked participants to provide lower/upper bounds in which they were 80% confident the true answer lay within.

RESULTS

There was a trend towards higher overconfidence for half-scale items in the schizophrenia and high-delusion-prone groups, which reached statistical significance for confidence-range items. However, accuracy was particularly low in the two delusional groups and a significant negative correlation between clinical delusional scores and overconfidence was observed for half-scale items within the schizophrenia group. Evidence in support of an association between overconfidence and delusional ideation was therefore mixed.

CONCLUSIONS

Inflated confidence-accuracy miscalibration for the two delusional groups may be better explained by their greater unawareness of their underperformance, rather than representing genuinely inflated overconfidence in errors.

Metacognitive therapy (MCT+) in patients with psychosis not receiving antipsychotic medication: A case study

Background: Psychotherapies for psychosis typically aim to develop an awareness of the implausible content of a delusion or target the underlying cognitive biases (i.e., problematic thinking styles, such as hasty decisions and illusory control) that foster and maintain delusional beliefs. A recently designed individual-based treatment entitled metacognitive therapy (MCT+) combines these two approaches. Emerging evidence suggests individualized MCT+, when used concurrently with antipsychotic medication, may be an effective psychological treatment for reducing delusional symptoms. However, it remains to be tested whether MCT+ can be effective in patients with active delusions who are not currently receiving psychotropic drugs.

Method: We present two cases (one patient with schizophrenia and the other with delusional disorder) experiencing active delusions who underwent 4-weeks of intensive MCT+, without concurrent antipsychotic medication (minimum 6-months unmedicated). Baseline and 6-week follow-up data are presented on a variety of measures assessing delusion symptom severity (i.e., PANSS, PSYRATS, SAPS), clinical insight, and cognitive bias propensity.

Results: After 4-weeks of MCT+, both patients showed substantial reduction in delusional symptoms, reported improved clinical insight, and were less prone to making illusory correlations.

Conclusions: The presented case studies provide preliminary evidence for the feasibility of MCT+ in treating patients not taking, or resistant to, antipsychotic medication.

Psychosocial Approaches in the Treatment of Psychosis: Cognitive Behavior Therapy for Psychosis (CBTp) and Metacognitive Training (MCT)

Although antipsychotic medication has been the most widely used and efficacious treatment in ameliorating the symptoms of psychosis, there has been a growing realization that pharmacological treatment has limitations. A significant minority of individuals continue to show "treatment-resistant" symptoms and significant relapse risk, while others show symptom reduction without the corresponding improvement in social and role functioning. Psychotherapy, in combination with medication, can help with symptom reduction, as well as improve functioning and quality of life. In this paper, we focus on two modalities of psychotherapy which have been shown to improve symptomatology and functioning in individuals with psychosis: Cognitive Behavior Therapy for psychosis (CBTp) and Metacognitive Training (MCT). Both treatment approaches focus on increasing the individuals' understanding of the psychological mechanisms associated with delusions and hallucinations, and helping them develop strategies to improve reality testing and belief evaluation. We aim to provide an overview of both treatments, examining not only the theoretical mechanisms and efficacy of each approach, but also the common therapeutic components they share.

Metacognitive training for patients with schizophrenia: preliminary evidence for a targeted, single-module programme

OBJECTIVE

Metacognitive training is an eight-module, group-based treatment programme for people with schizophrenia that targets the cognitive biases (i.e. problematic thinking styles) thought to contribute to the genesis and maintenance of delusions. The present article is an investigation into the efficacy of a shorter, more targeted, single-module metacognitive training programme, administered individually, which focuses specifically on improving cognitive biases that are thought to be driven by a 'hypersalience of evidence-hypothesis matches' mechanism (e.g. jumping to conclusions, belief inflexibility, reasoning heuristics, illusions of control). It was hypothesised that a more targeted metacognitive training module could still improve performance on these bias tasks and reduce delusional ideation, while improving insight and quality of life.

METHOD

A sample of 28 patients diagnosed with schizophrenia and mild delusions either participated in the hour-long, single-session, targeted metacognitive training programme (n = 14), or continued treatment as usual (n = 14). All patients were assessed using clinical measures gauging overall positive symptomology, delusional ideation, quality of life and insight, and completed two cognitive bias tasks designed to elucidate the representativeness and illusion of control biases.

RESULTS

After a 2-week, post-treatment interval, targeted metacognitive training patients exhibited significant decreases in delusional severity and conviction, significantly improved clinical insight, and significant improvements on the cognitive bias tasks, relative to the treatment-as-usual controls. Performance improvements on the cognitive bias tasks significantly correlated with the observed reductions in overall positive symptomology. Patients also evaluated the training positively.

CONCLUSIONS

Although interpretations of these results are limited due to the lack of an optimally designed, randomised controlled trial and a small sample size, the results are promising and warrant further investigation into targeted versions of the metacognitive training programme.

Metacognitive training (MCT) for schizophrenia improves cognitive insight: a randomized controlled trial in a Chinese sample with schizophrenia spectrum disorders

Metacognitive training (MCT) is a group-based treatment program for people with schizophrenia that targets the cognitive biases thought to contribute to the pathogenesis and maintenance of delusions. Although effective in reducing the severity of delusions, the influence of MCT on cognitive insight, and its feasibility in Chinese culture, has yet to be investigated. The present randomized-controlled trial attempted to address these inconsistencies. A Chinese sample of 80 participants with schizophrenia spectrum disorders was randomized to the eight-module MCT program or continued treatment as usual (TAU). All participants were assessed using the Beck Cognitive Insight Scale, which assesses two components of cognitive insight (self-reflectiveness and self-certainty). Participants in the MCT condition subjectively rated their satisfaction with the training. Retention rates were high after four-weeks of MCT (n = 38) or TAU (n = 39). Clients randomized into the MCT condition rated the program favourably and showed significant improvements in cognitive insight (i.e., increased self-reflectiveness), relative to TAU controls, who exhibited decreases in cognitive insight at follow-up. These findings suggest that the MCT program is not only subjectively efficacious in Chinese samples, but also improves metacognitive awareness of the processes underlying delusional symptoms.

Cognitive deficit awareness in schizophrenia: absent, intact, or somewhere in-between?

INTRODUCTION

Cognitive impairment is a pervasive feature of schizophrenia, and is a major determinant of the functional disability that is characteristic of the disorder. However, research investigating whether patients with schizophrenia show a deficit awareness remains unclear. The present study aimed to replicate and extend previous research comparing subjective and objective measures of cognition.

METHODS

. Thirty patients with a diagnosis of schizophrenia or schizoaffective disorder were administered the subjectively assessed Schizophrenia Cognitive Rating Scale (SCoRS) and the objective Brief Assessment of Cognition in Schizophrenia (BACS), which each assess overall global functioning and four specific neurocognitive domains (i.e., Verbal Memory, Working Memory, Processing Speed, and Reasoning and Problem Solving). Because deficit awareness may influence the likelihood of patients engaging in treatments designed to improve cognitive functioning, patients' attitudes towards such therapies were also contrasted with these subjective and objective measures of cognitive functioning.

RESULTS

Patients' subjective appraisals did not significantly correlate with the objective neuropsychological assessments for global functioning or any specific neurocognitive domains. However, patients accurately deduced that their memory domains were more impaired than the other domains, and there was a trend for patients to exaggerate their Reasoning and Problem Solving deficits. This suggests that patients show some level of deficit awareness, when overestimating "deficits" for domains that are not impaired. Finally subjective, but not objective, measures of cognitive functioning correlated significantly with willingness to participate in cognitive-enhancing therapies.

CONCLUSIONS

These results suggest that although patients' perceptions of their cognitive function are no substitute for objective neuropsychological test data, patients do possess a level of deficit awareness which may, in turn, influence willingness to participate in interventions such as cognitive rehabilitation.

Impaired integration of disambiguating evidence in delusional schizophrenia patients

BACKGROUND

It has been previously demonstrated that a cognitive bias against disconfirmatory evidence (BADE) is associated with delusions. However, small samples of delusional patients, reliance on difference scores and choice of comparison groups may have hampered the reliability of these results. In the present study we aimed to improve on this methodology with a recent version of the BADE task, and compare larger groups of schizophrenia patients with/without delusions to obsessive-compulsive disorder (OCD) patients, a population with persistent and possibly bizarre beliefs without psychosis.

METHOD

A component analysis was used to identify cognitive operations underlying the BADE task, and how they differ across four groups of participants: (1) high-delusional schizophrenia, (2) low-delusional schizophrenia, (3) OCD patients and (4) non-psychiatric controls.

RESULTS

As in past studies, two components emerged and were labelled 'evidence integration' (the degree to which disambiguating information has been integrated) and 'conservatism' (reduced willingness to provide high plausibility ratings when justified), and only evidence integration differed between severely delusional patients and the other groups, reflecting delusional subjects giving higher ratings for disconfirmed interpretations and lower ratings for confirmed interpretations.

CONCLUSIONS

These data support the finding that a reduced willingness to adjust beliefs when confronted with disconfirming evidence may be a cognitive underpinning of delusions specifically, rather than obsessive beliefs or other aspects of psychosis such as hallucinations, and illustrates a cognitive process that may underlie maintenance of delusions in the face of counter-evidence. This supports the possibility of the BADE operation being a useful target in cognitive-based therapies for delusions.

Over-adjustment or miscomprehension? A re-examination of the jumping to conclusions bias

OBJECTIVE

Previous research has consistently shown that individuals with delusions typically exhibit a jumping to conclusions (JTC) bias when administered the probabilistic reasoning 'beads task' (i.e. decisions made with limited evidence or 'premature decisions' and decisions over-adjusted in light of disconfirming evidence or 'over-adjustment'). More recent work, however, also suggests that these effects may also be influenced by miscomprehension of the task. The current paper is an investigation into the contributing effects of miscomprehension on the JTC bias.

METHOD

A total of 75 participants (25 diagnosed with schizophrenia with a history of delusions; 25 non-clinical delusion-prone; 25 non-delusion-prone controls) completed two identical versions of the beads task, distinct only by the inclusion of an extra instructional set designed to increase comprehension.

RESULTS

Qualitative data confirmed that miscomprehension is a valid construct, and the results showed that the addition of an instructional set to the second version of the task led to greater comprehension and a statistically significant drop in 'over-adjustment'. Nevertheless, both tasks showed that 'premature decisions' were significantly more prevalent in the schizophrenia group and were unaffected by the intervention.

CONCLUSIONS

It was concluded that the 'premature decisions' component of the JTC bias remains a feature of decision-making in schizophrenia, but that previously reported 'over-adjustment' effects are likely to be influenced by miscomprehension of the beads task instructional set. These findings are discussed in light of the recently proposed 'hypersalience of evidence-hypothesis matches' account of the JTC bias.