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.

Complementary group Metacognitive Training (MCT) reduces delusional ideation in schizophrenia.

BACKGROUND: Symptom reduction under antipsychotic agents is incomplete for most schizophrenia patients. In order to enhance outcome, cognitive approaches are increasingly adopted as add-on interventions. The present study aimed to determine the efficacy of group Metacognitive Training (MCT), which targets cognitive biases putatively involved in the pathogenesis of delusions. METHODS: A two-center, randomized, assessor-blind, controlled trial between MCT group training and cognitive training was carried out (ISRCTN95205723). A total of 150 in- and outpatients with DSM diagnoses of schizophrenia spectrum disorders were enrolled. All patients were concurrently prescribed antipsychotic medication. Assessments were made at baseline, four weeks and six months later. The primary outcome was a delusion score derived from the Positive and Negative Syndrome Scale (PANSS). The Psychotic Symptom Rating Scales (PSYRATS) as well as cognitive measures served as secondary outcomes. RESULTS: Completion at follow-up was 86%. According to intention-to-treat (ITT) analyses, patients in the MCT group showed significantly greater symptom reduction on the PANSS delusion subscore (follow-up), PANSS positive score (post-treatment) and PSYRATS delusion score (post-treatment and follow-up). Improvement on the PANSS positive scale at post-treatment and follow-up was positively correlated with the number of attended MCT sessions. No changes were seen for other psychopathological syndromes. DISCUSSION: MCT, a low-intensity training aimed at enhancing patients' awareness of cognitive biases subserving paranoia, led to improvement in delusion symptoms relative to the control condition and over and above the effects of antipsychotic medication. This improvement was sustained at follow-up.

Predictors of performance improvements within a cognitive remediation program for schizophrenia.

Cognitive impairment is regarded a core feature of schizophrenia and is associated with low psychosocial functioning. There is rich evidence that cognitive remediation can improve cognitive functions in patients with schizophrenia. However, little is known about what predicts individual remediation success. Some studies suggest that baseline cognitive impairment might be a limiting factor for training response. Aim of the current study was to further examine the role of cognitive and symptom variables as predictors of remediation success. We studied a total sample of 32 patients with schizophrenia and schizoaffective disorder who were engaged in a computer-based cognitive training program (CogPack). A pre-training test battery provided cognitive measures of selective attention, executive functioning, processing speed, verbal memory, and verbal intelligence along with measures for positive and negative symptoms. Training response was defined as improvement on training tasks. Correlation analyses revealed no significant relationship between any of the baseline cognitive or symptom measures and improvement rates. However, better baseline cognition was associated with a higher percentage of tasks with initial ceiling effects. We conclude that not carefully tailoring task difficulty to patients' cognitive abilities constitutes a much more severe threat to cognitive remediation success than cognitive impairment itself.

"Don't give me that look" - overconfidence in false mental state perception in schizophrenia.

Dysfunctions in social cognition are implicated in the pathogenesis of schizophrenia and have been extensively replicated over the years. For memory research, the administration of cognitive tasks with metacognitive aspects like confidence ratings has deepened our insight into how impairments contribute to symptoms of the disorder. A total of 76 patients with schizophrenia or schizoaffective disorder and a sample of 30 healthy participants were tested with the Reading the Mind in the Eyes test (Eyes-test). The Eyes-test was complemented with a rating scale requesting response confidence and was administered along with paradigms tapping neuropsychological parameters and cognitive insight. Schizophrenia patients showed impaired abilities on mental state perception. In addition, they committed more high-confidence errors and at the same time made fewer high-confidence correct responses. Impairments were most pronounced in patients with formal thought disorder. The patients displayed a decreased metacognitive awareness for their deficits. The results suggest that adding confidence ratings to the investigation of social cognition promises to advance our understanding of social cognition in schizophrenia. Patients not only show severe impairments in social cognition, but are overconfident in their judgments and lack cognitive insight into their deficits. The results highlight the need for metacognitive therapeutic approaches for the treatment of this population.