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

Insight in cognitive impairment assessed with the Cognitive Assessment Interview in a large sample of patients with schizophrenia

The Cognitive Assessment Interview (CAI) is an interview-based scale measuring cognitive impairment and its impact on functioning in subjects with schizophrenia (SCZ). The present study aimed at assessing, in a large sample of SCZ (n = 601), the agreement between patients and their informants on CAI ratings, to explore patients' insight in their cognitive deficits and its relationships with clinical and functional indices. Agreement between patient- and informant-based ratings was assessed by the Gwet's agreement coefficient. Predictors of insight in cognitive deficits were explored by stepwise multiple regression analyses. Patients reported lower severity of cognitive impairment vs. informants. A substantial to almost perfect agreement was observed between patients' and informants' ratings. Lower insight in cognitive deficits was associated to greater severity of neurocognitive impairment and positive symptoms, lower severity of depressive symptoms, and older age. Worse real-life functioning was associated to lower insight in cognitive deficit, worse neurocognitive performance, and worse functional capacity. Our findings indicate that the CAI is a valid co-primary measure with the interview to patients providing a reliable assessment of their cognitive deficits. In the absence of informants with good knowledge of the subject, the interview to the patient may represent a valid alternative.

Cognitive impairment in schizophrenia: aetiology, pathophysiology, and treatment

Cognitive deficits are a core feature of schizophrenia, account for much of the impaired functioning associated with the disorder and are not responsive to existing treatments. In this review, we first describe the clinical presentation and natural history of these deficits. We then consider aetiological factors, highlighting how a range of similar genetic and environmental factors are associated with both cognitive function and schizophrenia. We then review the pathophysiological mechanisms thought to underlie cognitive symptoms, including the role of dopamine, cholinergic signalling and the balance between GABAergic interneurons and glutamatergic pyramidal cells. Finally, we review the clinical management of cognitive impairments and candidate novel treatments.

Metacognitive training for psychosis (MCT): past, present, and future

This article provides an overview and retrospective on metacognitive training for psychosis (MCT), which first appeared approximately 2 decades ago. We recount how our empirical understanding of psychosis at that time led to the first preliminary version of the program. We describe setbacks and challenges that led to major changes, including revisions to existing modules (e.g., more focus on metacognitive variables, particularly on decision confidence as one of the primary targets of treatment) and the creation of new modules addressing mood, as well as attempts to improve sustainability of effects via homework exercises and a smartphone app ( www.uke.de/mct_app ). We have also enhanced dissemination efforts by creating new culturally sensitive language versions and facilitating low-threshold training through e-learning courses ( www.uke.de/e-mct ). Finally, we discuss several meta-analyses on the efficacy of MCT that have been published over the last decade. While reviews were initially inconsistent, possibly reflecting the insufficient statistical power and lower design quality of the first MCT studies, more recent meta-analyses have confirmed the efficacy of MCT on positive symptoms, insight, and cognitive biases, which has led to the inclusion of MCT in some national treatment guidelines for schizophrenia.

Executive dysfunction in schizophrenia: Predictors of the discrepancy between subjective and objective measures

This study aimed to investigate what characterizes individuals with schizophrenia who experience more or less subjective executive dysfunction in everyday life compared to objective executive performance on neuropsychological tests. Sixty-six participants with broad schizophrenia spectrum disorders completed a comprehensive assessment of executive function. Discrepancies between performance on neuropsychological tests (objective) and an extensive self-report questionnaire (subjective) of central executive functions (inhibition, shifting and working memory) were calculated. Higher level of self-efficacy was the best predictor of experiencing fewer subjective cognitive complaints compared to objective performance, followed by higher levels of disorganized symptoms. Depressive symptoms did not predict discrepancy between subjective and objective executive function. Higher estimated IQ predicted greater subjective working memory difficulties in everyday life despite better objective performance. Results may aid clinicians in the assessment and remediation of cognitive impairment. Low self-efficacy may identify individuals who are not able to utilize their potential executive functions in daily life. Interventions aimed at fostering self-efficacy ought to be included in cognitive remediation for these individuals. Disorganized symptoms could prove useful in identifying individuals who are in need of cognitive remediation for executive dysfunction, despite that they overestimate their skills. These individuals may benefit from efforts to increase insight into cognitive dysfunction.

Correlation between Performance-Based and Interview-Based Cognitive Measurements in Patients with Schizophrenia

OBJECTIVE

The Measurement and Treatment Research to improve Cognition in Schizophrenia Consensus Cognitive Battery (MCCB) is used to measure the cognitive function of patients with schizophrenia. In some situations, interview-based measures such as the Schizophrenia Cognition Rating Scale (SCoRS) may be appropriate. In this study, we analyzed the correlation between performance- and interview-based measurements in patients with schizophrenia.

METHODS

Fifty-six clinically stable patients were recruited. To evaluate cognitive function, we used the MCCB performance-based measure and the SCoRS interview-based measure. Measurements were taken at baseline, and 2 weeks and 3 months later. Spearman correlations were computed between each SCoRS item's interviewer rating and each MCCB score.

RESULTS

The correlation between the MCCB overall T score and the SCoRS global score was the strongest (r=-0.52), while the SCoRS total score and the MCCB Speed of Processing score also correlated (r=-0.48). The SCoRS global score showed statistically significant correlations with all seven MCCB domains and the overall T score.

CONCLUSION

This study reveals correlations between MCCB domains and SCoRS items. Since we find that interview-based measurements are highly correlated with performance-based measurements, we suggest them as a useful cognitive function evaluation tool that can easily be applied in clinical settings.

Divergence of subjective and performance-based cognitive gains following cognitive training in schizophrenia

BACKGROUND

Cognitive training is effective for improving cognitive performance among people with schizophrenia. An individual's perception of their own cognition is dissociable from performance on objective cognitive tests. Since subjective cognitive benefit may impact engagement, motivation, and satisfaction with time-intensive cognitive interventions, this study aimed to determine whether subjective cognitive difficulties improve in conjunction with cognitive gains following 30 h of cognitive training.

METHODS

Patients with schizophrenia or schizoaffective disorder (N = 46) were randomized to treatment as usual (TAU) or TAU augmented with auditory-targeted cognitive training (TCT). All participants completed assessment batteries at baseline and follow-up. As previously reported, the TCT group showed significant improvements in verbal learning and memory and reductions in auditory hallucinations relative to the TAU group.

RESULTS

Subjective cognitive difficulties did not significantly improve following TCT, even among TCT participants who showed improvements in cognitive performance (all ps > 0.05). Subjective cognitive difficulties were significantly associated with severity of depressive symptoms and hallucinations (r = 0.48 and r = 0.28, p < 0.001), but not global or specific domains of cognition (all rs < 0.1) at baseline. There were no significant relationships between change in subjective cognitive difficulties and change in cognitive or clinical variables (all ps > 0.05).

DISCUSSION

Patients with schizophrenia do not detect change in their cognition following cognitive training, even among those who showed robust gains in cognitive performance. Failure to detect improvement may undermine treatment engagement, motivation, and satisfaction. Translating score improvements on the cognitive exercises into tangible metrics, and providing ongoing, clinician-delivered feedback on performance may facilitate patient ability to detect improvements and improve motivation to engage with cognitive training interventions.

Monocausal attribution and its relationship with reasoning biases in schizophrenia

BACKGROUND

Aberrant attributional styles are counted to a set of circumscribed cognitive biases that are implicated in the pathogenesis of (paranoid) psychosis. However, evidence for a specific profile (e.g., an exaggerated self-serving bias, other-blaming bias) has become equivocal over the years. More recently, one-sided (monocausal) attributions have been reported in patients with psychosis.

METHODS

We compared a large sample of patients with diagnosed schizophrenia (n=145) to nonclinical controls (n=30) on a revised version of the Internal, Personal and Situational Attributions Questionnaire (IPSAQ-R). In this task, participants have to assign probability estimates to each of three potential causes (i.e., myself, others, circumstances) for a specific (negative or positive) event.

RESULTS

Participants with schizophrenia displayed an abolished self-serving bias and showed a significant preference for one-sided/monocausal attributions, which was neither correlated with jumping to conclusions nor overconfidence in errors. School education correlated with less monocausal attributions. We did not find any congruence between attributional styles with core delusional ideas.

CONCLUSIONS

Our study corroborates earlier investigations showing that monocausal attributions may play a role in the pathogenesis of psychosis; this bias unlikely represents an epiphenomenon of established biases. Unexpectedly, attributional styles (e.g., external-blaming) did not shape delusional contents. The true prevalence of monocausal attributions in psychosis is perhaps underestimated in the study, as groups were equated on school education, which was correlated with monocausal attributions.

Embracing Psychosis: A Cognitive Insight Intervention Improves Personal Narratives and Meaning-Making in Patients With Schizophrenia

Schizophrenia is a complex psychiatric disorder with unknown and presumably heterogeneous etiology. While the disorder can have various outcomes, research is predominantly "deficit-oriented" emphasizing the hardship that the disorder inflicts on sufferers as well as their families and society. Beyond symptom reduction, imparting patients with hope and meaning in life is increasingly considered an important treatment target, which may raise self-esteem, and reduce self-stigma and suicidal ideation. The present study compared a psychotherapeutic treatment aimed at improving cognitive insight, individualized metacognitive intervention (MCT+), with an active control in order to elucidate if personal meaning-making and hope can be improved in patients with psychosis across time. A total of 92 patients were randomized to either individualized metacognitive therapy (MCT+) or CogPack (neuropsychological training) and followed up for up to 6 months. The "Subjective Sense in Psychosis Questionnaire" (SUSE) was administered which covers different salutogenetic vs pathogenetic views of the disorder, valence of symptom experiences and the consequences of psychosis. Patients in the MCT+ group showed a significant positive shift in attitudes towards the consequences of their illness over time relative to patients in the active control condition. There was some evidence that MCT+ also enhanced meaning-making. The perceived negative consequences of psychosis were highly correlated with depression and low self-esteem, as well as suicidality. The study shows that a cognitive insight training can improve meaning-making in patients and help them come to terms with their diagnosis.

Self-Reported Cognitive Biases Are Equally Present in Patients Diagnosed With Psychotic Versus Nonpsychotic Disorders

We investigated the relation between subjective cognitive biases measured with the Dutch Davos Assessment of Cognitive Biases (DACOBS-NL) and (1) the presence of a psychotic versus nonpsychotic psychiatric disorder, (2) the current dose of antipsychotic medication and current psychotic symptoms, and (3) the Personality Inventory for the DSM-5 (PID-5) Psychoticism personality trait. Results showed that DACOBS-NL subjective cognitive biases (1) were equally present in patients diagnosed with nonpsychotic disorders compared with patients with a psychotic disorder, (2) could not be explained by the current dose of antipsychotic medication, nor by current psychotic symptoms, and (3) significantly correlated with all PID-5 Personality domains. Moreover, in predicting membership of the psychotic versus nonpsychotic psychiatric disorder group, the addition of the PID-5 domains in step 2 rendered the contribution of the DACOBS-NL subjective cognitive biases in step 1 nonsignificant. Further research is needed to clarify the interplay between cognitive biases and aberrant salience in the prediction of psychotic disorders.

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.

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.

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.

Current understandings about cognition and the neurobiological correlates in schizophrenia

Schizophrenia is a severe mental disorder. Cognitive deficits are one of the core features of schizophrenia. Multiple domains of cognition (executive function, attention/vigilance, working memory, verbal fluency, visuospatial skills, processing speed, and social cognition) are affected in patients with schizophrenia. Deficits in cognition led to impairment in the real world functioning. Identifying the cognitive deficits and early intervention is required for better functional outcome. This review focuses on conceptual understanding of cognition with its neurobiological correlates in schizophrenia and its different clinical implications.

[Subjective cognition in schizophrenia]

OBJECTIVES

Given the extent, magnitude and functional significance of the neurocognitive deficits of schizophrenia, growing attention has been paid recently to patients' self-awareness of their own deficits. Thus far, the literature has shown either that patients fail to recognize their cognitive deficits or that the association between subjective and objective cognition is weak in schizophrenia. The reasons for this lack of consistency remain unexplained but may have to do, among others, with the influence of potential confounding clinical variables and the choice of the scale used to measure self-awareness of cognitive deficits. In the current study, we sought to examine the relationships between subjective and objective cognitive performance in schizophrenia, while controlling for the influence of sociodemographic and psychiatric variables.

METHODS

Eighty-two patients with a schizophrenia-spectrum disorder (DSM-IV criteria) were recruited. Patients' subjective cognitive complaints were evaluated with the Subjective Scale to Investigate Cognition in Schizophrenia (SSTICS), the most frequently used scale to measure self-awareness of cognitive deficits in schizophrenia. Neurocognition was evaluated with working memory, planning and visual learning tasks taken from Cambridge Neuropsychological Tests Automated Battery. The Stroop Color-Word test was also administered. Psychiatric symptoms were evaluated with the Positive and Negative Syndrome Scale and the Calgary Depression Scale for Schizophrenia. The relationships between subjective and objective cognition were evaluated with multivariate hierarchic linear regression analyses, taking into consideration potential confounders such as sociodemographic and psychiatric variables. Finally, a factor analysis of the SSTICS was performed.

RESULTS

For the SSTICS total score, the regression analysis produced a model including two predictors, namely visual learning and Stoop interference performance, explaining a moderate portion of the variance. Visual learning performance was the most consistent predictor of most SSTICS subscores (e.g. episodic memory, attention, executive functioning, language and praxis). Modest associations were found between the PANSS cognitive factor and objective cognition (e.g. Stroop interference, visual learning, and working memory). Finally, the factor analysis revealed a 6-factor solution that echoes the classification of the items of the SSTICS based on the neuropsychological literature.

CONCLUSIONS

Using a scale having good internal validity, as shown by the factor analysis, the current study highlighted modest associations between subjective and objective cognitive performance, which suggests that schizophrenia patients are only partially aware of their own cognitive deficits. The results also showed a lack of correspondence between the impaired cognitive domain and the domain of cognitive awareness. It should be noted that clinicians were not better than patients at evaluating their cognitive deficits. Future research will need to determine if the observations reported here are schizophrenia-specific or not.

Cognitive impairment in schizophrenia across age groups: a case-control study

BACKGROUND

The potential dynamics of cognitive impairment in schizophrenia is discussed in the literature of the field. Recent publications suggest modest changes in level of cognitive impairment after first psychotic episode. Present article attempts to explore cognitive differences between patients and controls across age groups and differences between age groups in clinical group.

METHODS

One hundred and twenty-eight hospitalized patients with schizophrenia (64 women and 64 men) and 68 individuals from the control group (32 women and 32 men) aged 18-55 years were examined. The patients were divided into age groups (18-25, 26-35, 36-45, 46-55). Both groups were examined using Wisconsin Card Sorting Test, Rey Auditory Verbal Learning Test, Rey Osterrieth Complex Figure Test, Trail Making Test (A and B), Stroop Test, verbal fluency test and Wechsler digit span.

RESULTS

Patients with schizophrenia obtained significantly lower scores versus the control group in regard to all the measured cognitive functions (Mann-Whitney U; p < 0.05. Most deficits were present in all age groups, however, statistically important impairment in executive functions (WCST) were present only in "older" groups.

CONCLUSIONS

Patients with schizophrenia obtained less favourable results than the control group in all age groups. Deficits regarding executive functions do not seem to be at a significant level among the youngest group, whereas they are more noticeable in the group of 46-55-year-olds. Executive functions are significantly lowered in the group aged 36-45 in comparison to the "younger" groups. The level of cognitive functions shows a mild exacerbation in connection with age, whereas cognitive rigidity proved to be related to the number of years spent without hospital treatment.