Examining the presence and nature of delusions in Alzheimer's disease and frontotemporal dementia syndromes.

OBJECTIVES: Abnormal beliefs and delusions have been reported in some people with dementia, however, the prevalence of delusions, and their neurocognitive basis has been underexplored. This study aimed to examine the presence, severity, content and neural correlates of delusions in a large, well-characterised cohort of dementia patients using a transdiagnostic, cross-sectional approach. METHODS: Four-hundred and eighty-seven people with dementia were recruited: 102 Alzheimer's disease, 136 behavioural-variant frontotemporal dementia, 154 primary progressive aphasia, 29 motor neurone disease, 46 corticobasal syndrome, 20 progressive supranuclear palsy. All patients underwent neuropsychological assessment and brain magnetic resonance imaging, and the Neuropsychiatric Inventory was conducted with an informant, by an experienced clinician. RESULTS: In our cohort, 48/487 patients (10.8%) had delusions. A diagnosis of behavioural-variant frontotemporal dementia (18.4%) and Alzheimer's disease (11.8%) were associated with increased risk of delusions. A positive gene mutation was observed in 11/27 people with delusions. Individuals with frequent delusions performed worse on the Addenbrooke's Cognitive Examination (p = 0.035), particularly on the orientation/attention (p = 0.022) and memory (p = 0.013) subtests. Voxel-based morphometry analyses found that increased delusional psychopathology was associated with reduced integrity of the right middle frontal gyrus, right planum temporale and left anterior temporal pole. CONCLUSION: Our results demonstrate that delusions are relatively common in dementia and uncover a unique cognitive and neural profile associated with the manifestation of delusions. Clinically, delusions may lead to delayed or misdiagnosis. Our results shed light on how to identify individuals at risk of neuropsychiatric features of dementia, a crucial first step to enable targeted symptom management.

Appearance-based trust processing in schizophrenia.

OBJECTIVES: Schizophrenia is characterized by impaired social interactions and altered trust. In the general population, trust is often based on facial appearance, with limited validity but enormous social consequences. The aim was to examine trust processing in schizophrenia and specifically to examine how people with schizophrenia use facial appearance as well as actual partner fairness to guide trusting decisions. DESIGN: An experimental economic game study. METHODS: Here, we tested how patients with schizophrenia and control participants (each N = 24) use facial trustworthiness appearance and partner fairness behaviour to guide decisions in a multi-round Trust Game. In the Trust Game, participants lent money to 'partners' whose facial appearance was either untrustworthy or trustworthy, and who either played fairly or unfairly. Clinical symptoms were measured as well as explicit trustworthiness impressions. RESULTS: Overall, the patients with schizophrenia showed unimpaired explicit facial trustworthiness impressions and unimpaired facial appearance biases in the Trust Game. Crucially, patients and controls significantly differed so that the patients with schizophrenia did not learn to discriminate in the Trust Game based on actual partner fairness, unlike control participants. CONCLUSION: A failure to discriminate trust has important implications for everyday functioning in schizophrenia, as forming accurate trustworthiness beliefs is an essential social skill. Critically, without relying on more valid trust cues, people with schizophrenia may be especially susceptible to the misleading effect of appearance when making trusting decisions. PRACTITIONER POINTS: Findings People with schizophrenia made very similar facial trustworthiness impressions to healthy controls and also used facial appearance to guide trust decisions similarly to controls. However, the patient group were less able to explicitly distinguish between fair and unfair partners based on their behaviour compared with the control group. Moreover, people with schizophrenia failed to use actual partner fairness to guide their financial decisions in the Trust Game, unlike controls, and this impairment was specific to a social task. People with schizophrenia may be particularly reliant on facial appearance when trusting others, as they may struggle to incorporate more valid trustworthiness information in their decision-making, such as actual partner fairness.

Perceiving and attributing intentionality in schizophrenia.

Introduction: People with schizophrenia perform poorly on theory-of-mind (ToM) tasks. They also generate less mental-state language to describe test stimuli depicting intentionality. Some of these individuals also show excessive mentalising when objective cues of intentionality are absent. We tested perceiving and attributing intentionality to resolve this paradox. Methods: 23 schizophrenia patients and 20 healthy controls completed the chasing detection task to assess perceptual sensitivity to cues of intentionality. Other tasks assessed spontaneous attributions of intentionality (irrespective of accuracy) and accurate ToM inferences. Results: Perceptual sensitivity to cues of intentionality did not differ between groups. Patients were less likely to spontaneously attribute intentionality (irrespective of accuracy) or perform ToM tasks accurately. Chasing-detection response bias, but not perceptual sensitivity, correlated with attributions of intentionality. Referential (and to less extent) persecutory ideation associated with excessive mentalising when cues of intentionality were absent. Conclusions: Intentionality can be directly perceived, independent of attributions or inferences, in people with schizophrenia. We conclude that the flow of information from intact perceptual detection to evoke spontaneous attributions of intentionality is disrupted in schizophrenia, with flow-on detrimental effects on accurate ToM reasoning. Referential/persecutory ideation motivates inappropriate mentalising when objective cues of intentionality are absent.

"Formal Thought Disorder" in a General-Community Sample With Elevated Schizotypal Traits.

Different dimensions of formal thought disorder (FTD) are distinguished by different patterns of cognitive dysfunction and cortical variability in patients with schizophrenia; however, inconsistent findings may relate to patient-related confounds. Investigating FTD in nonpatient samples with elevated levels of schizotypal traits avoids these confounds, but its utility to FTD research is unknown. Thus, we performed principal components analysis (PCA) of FTD ratings using the Scale for the Assessment of Thought, Language, and Communication (TLC) and the Thought and Language Index (TLI) in a general-community sample with elevated schizotypal traits. Both scales showed "clinically elevated" FTD, particularly, the TLC. PCA described a three-component TLC solution ("disorganization," "verbosity," "emptiness") and a two-component TLI solution ("negative," "idiosyncratic"), generally consistent with schizophrenia research. TLC "disorganization" and "emptiness" were correlated with psychosis-like experiences. TLI "negative" was associated with lower general cognitive function, consistent with schizophrenia research. FTD may have shared etiology along the schizophrenia spectrum.

Contradiction processing in schizophrenia.

INTRODUCTION: Patients with schizophrenia present clinically with difficulties in manipulating contradictory information in the form of loose associations, surface contradictions and delusional beliefs. It is to date unclear whether patients can detect and process information that contradicts their beliefs and prior knowledge and whether this capacity is related to their symptoms and the nature of contradictory stimuli (e.g., personally significant information, emotional information). METHODS: We probed contradiction processing in patients with schizophrenia and healthy controls using sentence verification tasks that involve self-referential judgements (Experiment 1) and general knowledge (Experiment 2), while manipulating the emotional content of the stimuli. RESULTS: We found no differences between patients and controls either on reaction time (Experiment 1 & 2) or accuracy measures (Experiment 1). CONCLUSIONS: Our results show no general impairment in contradiction processing in schizophrenia. Rather, failures to detect and correct contradictions in symptoms such as formal though disorder or delusions could arise through a complex interplay between executive dysfunctions, stress and the emotional content of the information.

Outcome-focused judgements of moral dilemmas in schizophrenia.

Previous research on moral judgement in healthy adults suggests a complex interplay of automatic, emotional and deliberative processing. We aimed to advance understanding of these processes by examining moral judgement in individuals with schizophrenia, a population characterised by social-cognitive deficits and interpersonal difficulties. Forty-five patients with schizophrenia and 27 healthy controls judged high-conflict moral dilemmas in response to 3rd-person (i.e. "Is it morally okay to [perform X]?") and 1st-person (i.e. "Would you [perform X]?") probes. Controls were less utilitarian for 3rd-person than 1st-person probes, while this discrepancy did not hold for patients. Utilitarianism in patients correlated with higher levels of interpersonal conflict. Findings suggest that people with schizophrenia focus equally on outcomes across moral-judgement conditions that ought normally to elicit an outcome-action discrepancy, suggesting that they are less influenced by an automatic aversive response to harmful acts in dilemma scenarios, consistent with a dual-process model of moral judgement.

Judgment of moral and social transgression in schizophrenia.

INTRODUCTION: Despite evidence of pervasive social-cognitive deficits in schizophrenia, little is known of moral cognition in this population. While recent research indicates that impairment of explicit moral reasoning is explained by these individuals' other cognitive deficits, their capacities for basic moral judgment are unknown. METHODS: 45 people with schizophrenia and 27 healthy controls completed the Moral-Conventional Distinction Task: a classic task that assesses judgment of violations of moral or social convention on permissibility, severity, and authority-contingence. Justifications of judgments were also probed. Basic cognition was indexed by measures of IQ, verbal memory, and information processing speed. Self-report inventories were used to assess different facets of 'empathy' (e.g., perspective-taking, or theory of mind, and empathic concern), and aggressive tendencies. RESULTS: Groups did not differ significantly in judgments of permissibility or authority-contingency, or justifications of judgments. Patients did, however, rate violations of social (but not moral) convention more harshly. They also took longer to judge impermissibility of moral (but nor social) transgressions. Slower moral judgment in patients was associated with lower levels of self-reported empathic concern, while harsher condemnation of social transgression was associated with poorer (self-reported) perspective-taking. CONCLUSIONS: Findings provide no evidence that moral judgment is fundamentally compromised in schizophrenia. Evidence of slower moral judgment in schizophrenia does suggest, however, that patients were less influenced by automatic aversive responses to amoral conduct. The association found between poorer (self-reported) perspective-taking and greater condemnation of social transgressions also suggests that an insensitivity to others' extenuating motives may exacerbate social misunderstandings in schizophrenia.

Impairments of spontaneous and deliberative mentalizing co-occur, yet dissociate, in schizophrenia.

OBJECTIVES: Evidence of impairment in explicit mentalizing in people with schizophrenia has inspired interventions to improve awareness of others' mental states in these individuals. Less is known of implicit mentalizing in schizophrenia, with current findings mixed. We sought to resolve previous inconsistencies using Heider & Simmel's (H&S) classic animation to elicit spontaneous mentalizing and examined relations between spontaneous and deliberative mentalizing. METHODS: Forty-five schizophrenia outpatients and 27 general-community controls completed two explicit theory-of-mind (TOM) tasks and then described the H&S animation (to elicit spontaneous social attributions about emotionally driven, as well as goal-driven, behaviours), before and after an instruction to think of the shapes as people. Accuracy of basic and social facts and frequencies of personification and different mental-state terms were recorded. RESULTS: Explicit TOM performance was impaired in patients. Patients also generated fewer social (but not basic) facts than controls to describe the H&S animation, and used less mental-state language, before, and even more so, after the 'people' instruction, despite that both groups had used more personification terms after the 'people' instruction. Measures of explicit and spontaneous mentalizing contributed independently to discriminating between groups. CONCLUSIONS: Patients respond less to the bottom-up signals of agency that ought normally to elicit spontaneous social attributions, even when cued to think of the stimuli as people, and the stimuli depict emotionally driven, as well as goal-driven, behaviour. That impairments of spontaneous and deliberative mentalizing dissociate in schizophrenia suggests that training deliberative mentalizing may not be enough; interventions to improve spontaneous mentalizing are also needed. PRACTITIONER POINTS: Findings People with schizophrenia were less likely than controls to spontaneously attribute causal mental states when viewing dynamic signals of emotionally driven and goal-driven behaviours. These impairments were even more pronounced when participants were instructed to think of the stimuli as people, suggesting that perceiving others in social roles does not prompt people with schizophrenia to anthropomorphize about others as agents motivated by their own inner worlds. Impairments of spontaneous mentalizing were found to co-occur independently with explicit mentalizing deficits in schizophrenia, consistent with the claim that humans can access two distinct systems for understanding others' minds. Findings suggest that interventions to improve conscious deliberative mentalizing in schizophrenia may not be enough; we also need to target implicit mentalizing processes. Limitations The patient sample was chronic and only mildly symptomatic. As such, findings cannot be generalized to other stages and phases of the illness. All patients were also medicated, allowing for the possibility that automatic responses to socially salient stimuli may have been pharmacologically attenuated. Future research may examine whether unmedicated young people at ultra-high risk of psychosis show a similar profile of mentalizing impairment. Future work may also examine whether impairments of deliberative and spontaneous mentalizing associate differentially with social functioning and different cognitive domains in schizophrenia.

Assessing early processing of eye gaze in schizophrenia: measuring the cone of direct gaze and reflexive orienting of attention.

INTRODUCTION: The accurate discrimination of another person's eye-gaze direction is vital as it provides a cue to the gazer's focus of attention, which in turn supports joint attention. Patients with schizophrenia have shown a "direct gaze bias" when judging gaze direction. However, current tasks do not dissociate an early perceptual bias from high-level top-down effects. We investigated early stages of gaze processing in schizophrenia by measuring perceptual sensitivity to fine deviations in gaze direction (i.e., the cone of direct gaze: CoDG) and ability to reflexively orient to locations cued by the same deviations. METHODS: Twenty-four patients and 26 controls completed a CoDG discrimination task that used realistic direct-face images with six fine degrees of deviation (i.e., 3, 6 or 9 pixels to the left and right) and direct gaze, and a gaze cueing task that assessed reflexive orienting to the same fine-grained deviations. RESULTS: Our data showed patients exhibited no impairment in gaze discrimination, nor did we observe a reduced orienting response. CONCLUSIONS: These results suggest that while patients may suffer deficits associated with interpreting another person's gaze, the earliest processes concerned with detecting averted gaze and reflexively orienting to the gazed-at location are intact.

Beliefs about hearing voices.

People who experience auditory verbal hallucinations (AVHs) vary in whether they believe their AVHs are self-generated or caused by external agents. It remains unclear whether these differences are influenced by the "intensity" of the voices, such as their frequency or volume, or other aspects of their phenomenology. We examined 35 patients with schizophrenia or schizoaffective disorder who experienced AVHs. Patients completed a detailed structured interview about their AVHs, including beliefs about their cause. In response, 20 (57.1%) reported that their AVHs were self-generated, 9 (25.7%) were uncertain, and 6 (17.1%) reported that their AVHs were caused by external agents. Several analytical approaches revealed little or no evidence for associations between either AVH intensity or phenomenology and beliefs about the AVH's cause; the evidence instead favoured the absence of these associations. Beliefs about the cause of AVHs are thus unlikely to be explained solely by the phenomenological qualities of the AVHs.

A quasi-randomized feasibility pilot study of specific treatments to improve emotion recognition and mental-state reasoning impairments in schizophrenia.

BACKGROUND: Impaired ability to make inferences about what another person might think or feel (i.e., social cognition impairment) is recognised as a core feature of schizophrenia and a key determinant of the poor social functioning that characterizes this illness. The development of treatments to target social cognitive impairments as a causal factor of impaired functioning in schizophrenia is of high priority. In this study, we investigated the acceptability, feasibility, and limited efficacy of 2 programs targeted at specific domains of social cognition in schizophrenia: "SoCog" Mental-State Reasoning Training (SoCog-MSRT) and "SoCog" Emotion Recognition Training (SoCog-ERT). METHOD: Thirty-one participants with schizophrenia or schizoaffective disorder were allocated to either SoCog-MSRT (n = 19) or SoCog-ERT (n = 12). Treatment comprised 12 twice-weekly sessions for 6 weeks. Participants underwent assessments of social cognition, neurocognition and symptoms at baseline, post-training and 3-months after completing training. RESULTS: Attendance at training sessions was high with an average of 89.29 % attendance in the SoCog-MSRT groups and 85.42 % in the SoCog-ERT groups. Participants also reported the 2 programs as enjoyable and beneficial. Both SoCog-MSRT and SoCog-ERT groups showed increased scores on a false belief reasoning task and the Reading the Mind in the Eyes test. The SoCog-MSRT group also showed reduced personalising attributional biases in a small number of participants, while the SoCog-ERT group showed improved emotion recognition. CONCLUSIONS: The results are promising and support the feasibility and acceptability of the 2 SoCog programs as well as limited efficacy to improve social cognitive abilities in schizophrenia. There is also some evidence that skills for the recognition of basic facial expressions need specific training. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12613000978763 . Retrospectively registered 3/09/2013.

An experimental investigation of mentalization ability in borderline personality disorder.

OBJECTIVE: Deficits in mentalization ability have been theorized to underlie borderline personality disorder (BPD) and have led to mentalization-based treatments. Yet there has been little empirical investigation into whether mentalization deficits do differentiate the BPD population from healthy controls, and the specific nature of these differences. METHOD: Five pre-existing Theory of Mind (ToM) tasks that assessed simple to complex mentalization capacity in both the affective and cognitive domains were administered to the same groups of age and gender matched patients with BPD and controls. Self-report measures assessed cognitive and affective empathy and childhood trauma and abuse. RESULTS: The BPD group did not differ significantly from the healthy control group on basic cognitive false-belief picture-sequencing tasks, or on overall accuracy when discriminating mental states from viewing images of eyes, and attributing emotions based on social events. They were, however, significantly less accurate in identifying positive mental states on the Reading the Mind in the Eyes (RME) task and showed significantly more mentalization errors on affective and cognitive understanding of faux pas (faux pas total score p<.01) and on a Joke Appreciation task (p=.01), that required integration of multiple perspectives. They also self-reported less empathic perspective taking (p<.01). Observation of patterns of performance hinted at specific underlying biases (e.g. a default tendency to use superficial black-and-white attributions to others, such as, "he is mean", when explaining behavior). It was also found that as childhood experiences of punishment increased, adulthood mentalization ability decreased on all affective ToM tasks and on the cognitive and affective components of understanding faux pas. CONCLUSIONS: The BPD group was as capable as controls in undertaking simple mentalization. However, deficits in mentalization capacity became evident when mentalization tasks became more complex and required the integration of multiple perspectives. Increasing childhood experiences of punishment were related to decreasing mentalization ability in adulthood. Findings support the use of treatments to improve mentalization skills in BPD, however, further research is needed to better specify the nature of underlying mentalizing biases in this population.

The Relationship Between Schizotypy and Reactive Aggression in Western Adults Is Mediated by Victimization.

A large body of literature suggests that schizophrenia and nonclinical schizotypal personality traits, or "schizotypy," are associated with increased aggression. However, recent studies focused on school-aged Asian samples have examined the relationship between schizotypal personality and 2 distinct forms of aggression: reactive and proactive aggression. This study aimed to investigate whether schizotypal personality traits would be associated more strongly with reactive, compared with proactive, aggression in an adult Western sample and whether victimization experiences mediated the schizotypy-reactive aggression relation. One hundred twenty-one Australian university undergraduates completed self-report inventories measuring levels of schizotypal personality, reactive and proactive aggression, and victimization. Results showed that, as hypothesized, schizotypal personality traits were more strongly associated with reactive than proactive aggression and that victimization experiences mediated the schizotypy-reactive aggression relationship. While acknowledging the limitations of nonclinical schizotypy research, the findings are discussed with regard to possible implications for the treatment of aggression in schizophrenia.

Analytic cognitive style, not delusional ideation, predicts data gathering in a large beads task study.

INTRODUCTION: It has been proposed that deluded and delusion-prone individuals gather less evidence before forming beliefs than those who are not deluded or delusion-prone. The primary source of evidence for this "jumping to conclusions" (JTC) bias is provided by research that utilises the "beads task" data-gathering paradigm. However, the cognitive mechanisms subserving data gathering in this task are poorly understood. METHODS: In the largest published beads task study to date (n = 558), we examined data gathering in the context of influential dual-process theories of reasoning. RESULTS: Analytic cognitive style (the willingness or disposition to critically evaluate outputs from intuitive processing and engage in effortful analytic processing) predicted data gathering in a non-clinical sample, but delusional ideation did not. CONCLUSION: The relationship between data gathering and analytic cognitive style suggests that dual-process theories of reasoning can contribute to our understanding of the beads task. It is not clear why delusional ideation was not found to be associated with data gathering or analytic cognitive style.

Perception, cognition, and delusion.

Firestone & Scholl's (F&S) critique of putative empirical evidence for the cognitive penetrability of perception focuses on studies of neurologically normal populations. We suggest that a comprehensive exploration of the cognition-perception relationship also incorporate work on abnormal perception and cognition. We highlight the prominence of these issues in contemporary debates about the formation and maintenance of delusions.

Re-examining Kohlberg's conception of morality in schizophrenia.

INTRODUCTION: Early clinical descriptions of and research with people with schizophrenia described apparent difficulties in moral judgement and sensitivity. However, this research failed to take into account the effect of cognitive deficits and symptoms on task performance. METHODS: We assessed people with schizophrenia on the Moral Judgement Interview, a task used in the earlier literature, alongside a battery of neuro- and social-cognitive tasks. RESULTS: Whereas people with schizophrenia perform more poorly on this task than controls, this is mediated by memory and declarative theory of mind, and also impacted by negative symptoms. CONCLUSIONS: These results indicate that performance deficits on moral judgement tasks are not a universal feature of schizophrenia, but rather due to associated difficulties such as those in social cognition.

Theory of mind and neurocognition in early psychosis: a quasi-experimental study.

BACKGROUND: People with chronic psychosis often display theory of mind impairments that are not fully accounted for by other, more general neurocognitive deficits. In these patients, both theory of mind and neurocognitive deficits contribute to poor functioning, independently of psychotic symptoms. In young people with recent-onset psychosis, however, it is unclear the extent to which theory of mind impairment is independent of neurocognitive deficits. The primary aim of this study was to examine the evidence for specific theory of mind impairments in early psychosis. A secondary aim was to explore the relations between theory of mind, neurocognition, symptom severity, and functional outcomes. METHODS: Twenty-three patients who were within two years of their first psychotic episode and 19 healthy controls completed theory of mind and neurocognitive batteries. Social functioning, quality of life, and symptom severity were also assessed in patients. RESULTS: Patients demonstrated deficits in tasks assessing theory of mind and neurocognition relative to controls. Patients' deficits in theory of mind were evident even after adjusting for their deficits in neurocognition. Neither theory of mind nor neurocognition predicted social functioning or quality of life in this early psychosis sample. Severity of negative symptoms, however, was a significant predictor of both outcomes. CONCLUSIONS: While a specific theory of mind impairment was evident in this early psychosis sample, severity of negative symptoms emerged as the best predictor of poor functional outcome. Further early psychosis research is needed to examine the longitudinal progression of theory of mind impairments - independent of neurocognitive deficits - and their impact on psychosocial function.

Moral cognition in schizophrenia.

INTRODUCTION: Disordered moral behaviour and understanding of moral rules were described early in the literature on schizophrenia; however, moral cognition has received scant attention in spite of a large literature focused on social cognitive impairments and violent behaviour in schizophrenia. METHODS: We conducted a narrative synthesis of the literature on violence, moral judgement and schizophrenia. RESULTS: Initial empirical research into moral cognition in schizophrenia did not fully account for the basic- and social-cognitive deficits now known to characterise schizophrenia. Importantly, research into moral cognition in autism and psychopathy, disorders in part characterised by social cognitive impairments indicates subtle patterns of difference to the moral cognition of control participants. Recent neuroeconomic studies of moral cognition in schizophrenia have indicated that individuals with schizophrenia display subtle dysfunction in their fairness-related behaviours, but not in their propensity to engage in altruistic punishment. CONCLUSIONS: Further research has the potential to broaden our understanding of what is intact and what is impaired in moral cognition in schizophrenia and also to inform our theories of the structures subserving moral judgement in the general population. Furthermore, a more thorough understanding of moral cognitive impairments in schizophrenia may have implications for both legal process and psychosocial rehabilitation.

Delusions and prediction error: re-examining the behavioural evidence for disrupted error signalling in delusion formation.

INTRODUCTION: There is now significant evidence that prediction error signalling is mediated by dopamine in the midbrain, and that dopamine dysfunction is implicated in people experiencing psychotic symptoms, including delusions. There has also been significant theorizing and experimentation concerning the remaining link in this triad, namely that deviant prediction error signalling produces or maintains psychotic symptoms. METHODS: The research supporting the link between prediction error signalling and delusional symptoms was reviewed. Numerous studies indirectly support this link, but only one set of studies claim to directly test this hypothesis by combining three crucial elements: a patient sample, a manipulation of prediction error and neuroimaging. This particular set of studies were examined in detail. RESULTS: Important methodological limitations in these studies were observed, and a reinterpretation of their data was offered. CONCLUSIONS: Methodological inconsistencies significantly weaken the claims made by these studies, but their data are consistent with current theorizing and they are instructive for future lines of inquiry in this field.