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Different dimensions of formal thought disorder (FTD) are distinguished by different patterns of cognitive dysfunction in patients with schizophrenia; however, inconsistent findings may relate to patient-related confounds. To avoid these confounds, we examined relationships between FTD dimensions and cognitive domains in a non-clinical sample with attenuated schizophrenia-like traits, or schizotypal traits, on the Schizotypal Personality Questionnaire (N = 91). To our knowledge, no study has done this. FTD dimension scores were derived following principal component analysis of the Scale for the Assessment of Thought, Language and Communication (TLC dimensions: Disorganisation, Verbosity, Emptiness) and the Thought and Language Index (TLI dimensions: Negative, Idiosyncratic). The sample completed a comprehensive neuropsychological battery. Findings indicate that higher-order reasoning, executive function (set shift and generative ability) and language/semantic functioning are the primary drivers of FTD in our non-clinical sample with elevated schizotypal traits, in line with schizophrenia research. FTD may have shared aetiology along the schizophrenia spectrum., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Body perception can be altered in individuals with schizophrenia resulting in experiences of undefined boundaries, loss of ownership, and size changes. These individuals may also be more susceptible to the rubber hand illusion (RHI: an illusion of body perception that can also be induced in neurotypical populations), but the findings are mixed. Furthermore, the perception of multisensory timing, which is thought to be fundamental for body perception, is altered in schizophrenia. We tested whether altered perception of the temporal relationship between visual and tactile signals in schizophrenia predicts self-reported perceptual aberrations and RHI susceptibility. We found that the sensitivity to detect temporal asynchronies is reduced in schizophrenia and this is a significant predictor for bodily perceptual symptoms. In contrast, we found no evidence for a direct relationship between asynchrony detection sensitivity and RHI susceptibility. Instead, our findings suggest that experiencing more bodily perceptual symptoms increases the likelihood of endorsing unusual bodily experiences, resulting in higher RHI self-ratings but not higher proprioceptive drift scores. Our findings provide new insight into factors that may underlie the report of unusual body perceptions in schizophrenia., Competing Interests: Declaration of competing interest The authors have declared that there are no conflicts of interest in relation to the subject of this report., (Copyright © 2020 Elsevier B.V. All rights reserved.)

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.

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., (© 2019 The British Psychological Society.)

This study investigated social cognition in schizophrenia using a virtual reality paradigm to capture the dynamic processes of evaluating and responding to eye gaze as an intentional communicative cue. A total of 21 patients with schizophrenia and 21 age-, gender-, and IQ-matched healthy controls completed an interactive computer game with an on-screen avatar that participants believed was controlled by an off-screen partner. On social trials, participants were required to achieve joint attention by correctly interpreting and responding to gaze cues. Participants also completed non-social trials in which they responded to an arrow cue within the same task context. While patients and controls took equivalent time to process communicative intent from gaze shifts, patients made significantly more errors than controls when responding to the directional information conveyed by gaze, but not arrow, cues. Despite no differences in response times to gaze cues between groups, patients were significantly slower than controls when responding to arrow cues. This is the opposite pattern of results previously observed in autistic adults using the same task and suggests that, despite general impairments in attention orienting or oculomotor control, patients with schizophrenia demonstrate a facilitation effect when responding to communicative gaze cues. Findings indicate a hyper-responsivity to gaze cues of communicative intent in schizophrenia. The possible effects of self-referential biases when evaluating gaze direction are discussed, as are clinical implications.

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.

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., (© 2017 The British Psychological Society.)

Theory of mind (TOM) impairments associate significantly with executive deficits in schizophrenia, consistent with the proposal that executive abilities can limit TOM task performance, and confounding identification of those patients who would benefit most from targeted mentalising interventions. 50 schizophrenia patients and 30 healthy controls completed an executive battery and four TOM tasks that were alike with regards generating overt measures of causal false-belief reasoning, but differed with regards using indirect (vs. more direct) instructions. Only the TOM tasks that used indirect instructions to elicit spontaneous false-belief inferences revealed impairment, independent of executive dysfunction, in the schizophrenia patients., (Copyright © 2017. Published by Elsevier B.V.)

Explicit tests of social cognition have revealed pervasive deficits in schizophrenia. Less is known of automatic social cognition in schizophrenia. We used a spatial orienting task to investigate automatic shifts of attention cued by another person's eye gaze in 29 patients and 28 controls. Central photographic images of a face with eyes shifted left or right, or looking straight ahead, preceded targets that appeared left or right of the cue. To examine automatic effects, cue direction was non-predictive of target location. Cue-target intervals were 100, 300, and 800 ms. In non-social control trials, arrows replaced eye-gaze cues. Both groups showed automatic attentional orienting indexed by faster reaction times (RTs) when arrows were congruent with target location across all cue-target intervals. Similar congruency effects were seen for eye-shift cues at 300 and 800 ms intervals, but patients showed significantly larger congruency effects at 800 ms, which were driven by delayed responses to incongruent target locations. At short 100-ms cue-target intervals, neither group showed faster RTs for congruent than for incongruent eye-shift cues, but patients were significantly slower to detect targets after direct-gaze cues. These findings conflict with previous studies using schematic line drawings of eye-shifts that have found automatic attentional orienting to be reduced in schizophrenia. Instead, our data indicate that patients display abnormalities in responding to gaze direction at various stages of gaze processing-reflected by a stronger preferential capture of attention by another person's direct eye contact at initial stages of gaze processing and difficulties disengaging from a gazed-at location once shared attention is established.

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., (Copyright © 2017. Published by Elsevier Inc.)

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.

The onset of schizophrenia is typically preceded by a prodromal period lasting several years during which sub-threshold symptoms may be identified retrospectively. Clinical interviews are currently used to identify individuals who have an ultra-high risk (UHR) of developing a psychotic illness with a view to provision of interventions that prevent, delay or reduce severity of future mental health issues. The utility of bio-markers as an adjunct in the identification of UHR individuals is not yet established. Several event-related potential measures, especially mismatch-negativity (MMN), have been identified as potential biomarkers for schizophrenia. In this 12-month longitudinal study, demographic, clinical and neuropsychological data were acquired from 102 anti-psychotic naive UHR and 61 healthy controls, of whom 80 UHR and 58 controls provided valid EEG data during a passive auditory task at baseline. Despite widespread differences between UHR and controls on demographic, clinical and neuropsychological measures, MMN and P3a did not differ between these groups. Of 67 UHR at the 12-month follow-up, 7 (10%) had transitioned to a psychotic illness. The statistical power to detect differences between those who did or did not transition was limited by the lower than expected transition rate. ERPs did not predict transition, with trends in the opposite direction to that predicted. In exploratory analysis, the strongest predictors of transition were measures of verbal memory and subjective emotional disturbance., Competing Interests: The authors have declared that no competing interests exist.

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.

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., (Copyright © 2016. Published by Elsevier Inc.)

Schizophrenia is associated with significant impairments in both higher and lower order social cognitive performance and these impairments contribute to poor social functioning. People with schizophrenia report poor social functioning to be one of their greatest unmet treatment needs. Recent studies have suggested the potential of oxytocin as such a treatment, but mixed results render it uncertain what aspects of social cognition are improved by oxytocin and, subsequently, how oxytocin might best be applied as a therapeutic. The aim of this study was to determine whether a single dose of oxytocin improved higher-order and lower-order social cognition performance for patients with schizophrenia across a well-established battery of social cognition tests. Twenty-one male patients received both a single dose of oxytocin nasal spray (24IU) and a placebo, two weeks apart in a randomized within-subjects placebo controlled design. Following each administration, participants completed the social cognition tasks, as well as a test of general neurocognition. Results revealed that oxytocin particularly enhanced performance on higher order social cognition tasks, with no effects on general neurocognition. Results for individual tasks showed most improvement on tests measuring appreciation of indirect hints and recognition of social faux pas. These results suggest that oxytocin, if combined to enhance social cognition learning, may be beneficial when targeted at higher order social cognition domains. This study also suggests that these higher order tasks, which assess social cognitive processing in a social communication context, may provide useful markers of response to oxytocin in schizophrenia., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Twenty-four patients with schizophrenia and 18 controls detected chasing in displays of moving disks. Compared to controls, patients had relatively higher hit rates for less direct compared to more direct chasing trials. Perceiving intent was generally intact in patients, despite the well-known difficulties with inferring intentional mental states in schizophrenia., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Dehaene et al. (2003) showed an absence of conscious, but not masked, conflict effects when patients with schizophrenia performed a number-categorisation priming task. We aimed to replicate these influential results using a different word-categorisation priming task. Counter to Dehaene et al.'s findings, 21 patients and 20 healthy controls showed similar congruence effects for both masked and visible primes. Within patients, a reduced congruence effect for visible primes associated with longer duration of illness and more severe behavioural disorganisation. Patients, unlike controls, were no slower to respond to targets that followed visible compared to masked primes. Conscious conflict effects on priming tasks are not universally reduced in schizophrenia but may associate with chronicity and behavioural disorganisation. That patients were no slower when the preceding primes were clearly visible accords with evidence elsewhere that information processing in schizophrenia is driven more by immediate conscious experience and constrained less by prior events., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Objective: Social cognition is profoundly impaired in patients with schizophrenia. This study describes 'Mental-State Reasoning Training for Social Cognitive Impairment' (SoCog-MSRT), a 5-week program developed to improve social cognition in patients with schizophrenia. We aimed to investigate the feasibility of implementing SoCog-MSRT in a rehabilitation setting and to evaluate whether our training methods produced improvements. METHOD The feasibility and benefits of SoCog-MSRT were evaluated in an open clinical trial with 14 participants with schizophrenia or schizoaffective disorder. Training comprised 10 twice-weekly sessions, for 5 weeks, with a pre- and post-training assessment., Results: There were significant improvements on: (a) a classic false-belief test of Theory of Mind (ToM); (b) inferring complex mental states from the eyes; and (c) a self-reported measure of social understanding. Some of these improvements were associated with baseline levels of working memory and premorbid Intelligence Quotient (IQ). CONCLUSIONS SoCog-MSRT can improve ToM abilities and social understanding, but individuals with poorer working memory and lower premorbid IQ may be less able to benefit from this type of training.

People with schizophrenia who experience auditory-verbal hallucinations experience difficulty in determining the source (self vs. other) of verbal information, and those with visual hallucinations experience a conceptually similar problem with visual information. In this study, we examined whether such source monitoring deficits extend to olfaction for olfactory hallucinators and whether they are selective to the modality in which the hallucination is experienced. To test these claims, three groups were formed: normal controls (NC), people with schizophrenia who experience olfactory hallucinations (OH), and people with schizophrenia who experience auditory-verbal hallucinations (AVH). These three groups were then tested on both an olfactory and an auditory-verbal source-monitoring task. We found evidence of a modality-specific impairment. The OH group was less accurate in determining whether an odor had been imagined or smelled relative to NC and AVH groups. In contrast, the AVH group was least accurate in determining the source of a word, relative to the OH and NC groups. These findings provide the first evidence of a source-monitoring impairment in schizophrenic participants with OHs and suggest that this impairment is modality specific., ((PsycINFO Database Record (c) 2012 APA, all rights reserved).)

Olfactory hallucinations (OHs) are present in a significant minority of people with schizophrenia, yet these symptoms are under-researched and poorly understood. This study aimed to identify the neuropsychological impairments that associate with OHs in schizophrenia. Patients with schizophrenia or schizoaffective disorder were classified into an OH group and a group with auditory-verbal hallucinations (AVHs) and no lifetime history of OHs. Patients were age- and gender-matched to a healthy control group. All participants were assessed using: a test of odor identification; decision-making and socio-emotional tests of orbitofrontal cortex (OFC) and amygdala function; and a battery of standardized executive tests. Patients, as a whole, performed more poorly than controls on the tests of odor identification, emotion processing and executive function, consistent with previous research. Only two tests of OFC functioning: the Object Alternation Task, taken from Oscar-Berman and Zola-Morgan's (1980a, 1980b) Comparative Neuropsychological Tasks, and a test of "faux pas" understanding discriminated between the OH and AVH patients. Findings provide the first preliminary support for OH-specific neuropsychological impairments associated with OFC dysfunction in schizophrenia. (JINS, 2012, 18, 1-10).

Introduction: It is well established that people with schizophrenia have impaired olfactory perception. However, another olfactory abnormality that occurs in schizophrenia--olfactory hallucinations (OHs)--has received almost no attention., Methods: This preliminary study compared a small sample of olfactory (OH; n=14) and auditory-verbal (AVH; n=11) hallucinators with schizophrenia, with matched healthy controls (NC; n=21), on tests of odour detection threshold, identification, and hedonics, and bespoke tests relating to possible causes of OHs., Results: Both OH and AVH participants were equally impaired on tests of odour identification, but neither had any impairment in detection. However, although the AVH group had hedonic impairments, these were not evident in the OH and NC groups. Examination of the possible causes of OHs revealed abnormalities in olfactory habituation. In addition, we observed a far greater rate of past episodes of brief unconsciousness in the OH group., Conclusions: The presence of habituation deficits and past episodes of brief unconsciousness, and absence of olfactory affective impairment, have not been identified before as correlates of OHs, suggesting these factors may be worthy of further investigation.

Poor social skills and abnormal behaviors are key features of schizophrenia and comprise important aspects of social functioning. Previous studies have shown that impairment of a social cognitive capacity for mental state attribution may be predictive of poor social skills. Poor social skills also seem to be related to the presence of negative symptoms, whereas the association with other symptom domains seems less clear. The contribution of nonsocial cognition, particularly executive functioning, to functional outcome in schizophrenia, and the relationships between social and nonsocial cognition, continue to be debated. To examine the relationships of mental state attribution with social skills, neurocognition and clinical symptomatology, we pooled data from two previous independent studies into one sample of 69 patients with schizophrenia. The sample was stratified for IQ, age range, and attention deficits. We also used a novel five-factor model of the Positive and Negative Syndrome Scale. A combined verbal and non-verbal score of mental state attribution was the best cognitive predictor of social skills, whereas neurocognition (i.e., executive planning skills) did not mediate this effect. When measures of psychopathology were included, levels of disorganized and negative symptoms predicted large proportions of variance in social functioning. Nevertheless, mental state attribution remained the sole, significant cognitive predictor variable in the equation. In conclusion, a capacity for mental state attribution is uniquely important for social skills in schizophrenia. As such, training to target social cognitive skills, including mental state attribution, may be particularly beneficial for patients' social functioning., (Copyright © 2010. Published by Elsevier Ireland Ltd.)

OBJECTIVES. Olfactory hallucinations (OHs) are underrepresented in conventional clinical instruments, infrequently researched, and poorly understood. To advance understanding of OHs, we examined their past-month prevalence and co-occurring symptoms in two datasets. DESIGN. One dataset comprised categorical codes and was examined using homogeneity analysis and logistic regression; the other dataset comprised numeric ratings and was examined using principal components analyses and linear regression. METHOD. The two datasets included: (1) 962 cases with Present State Examination - 9th Edition (PSE-9), codes (recoded present/absent) from the World Health Organization 10 Country (WHO-10) Study and (2) 265 cases with ratings on Scales for Assessing Positive/Negative Symptoms of Schizophrenia (SAPS/SANS). Two PSE-9 items (external- and self-smells) were recoded into a single OH item to examine consistency with the SAPS/SANS dataset, which contained a single OH item. RESULTS. Prevalence of OHs and hallucinations in other modalities differed according to the WHO-10 international centre. Across centres, OHs were present in 13% of the WHO-10 dataset, similar to the 17% prevalence rate in the SAPS/SANS dataset. Referential/control delusions and other hallucinations (particularly, somatic/tactile/gustatory hallucinations) were significant independent correlates of OHs in both datasets. OHs also co-occurred with social anxiety and depression in the WHO-10 dataset, with self-smells being particularly associated with self-depreciation. CONCLUSIONS. Sociocultural factors may modulate the self-reporting and/or detection of OHs and hallucinations in other modalities. Referential/control delusions promote the generation and/or maintenance of OHs independent of factors shared with other hallucinations. OHs and hallucinations of taste, touch, and bodily sensation frequently co-occur. Self-smells warrant sensitive probing., (©2010 The British Psychological Society.)

Olfactory hallucinations (OHs), so it has been argued, are prognostic of a poorer outcome, are unpleasant, and cannot be well explained within current theoretical accounts of hallucinations. We examined these and related issues by conducting structured interviews with 51 participants who experienced OHs and who were previously diagnosed with schizophrenia or schizoaffective disorder. We found no relationship between disease severity measures and type or frequency of OHs. As with prior research, we too noted the predominance of negative OHs, but with many reports of positive OHs, and also found significant relationships between frequency of OHs and severity of tactile hallucinations. We then examined whether odor imagery or involuntary memory might account for the presence of OHs, but these possibilities were not well supported. We then explored, using cluster analysis, whether or not our sample was homogenous. Two clusters were of especial interest; one which may reflect a 'sensory dysfunction group' and one characterized by more severe tactile hallucinations. The presence of tactile hallucinations may suggest a further novel cause of OHs, which we discuss. Our data suggest diverse causes for OHs in schizophrenia, none of which are consistent with current models of hallucinations in other modalities., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Deluded people differ from nondeluded controls on attributional style questionnaires and probabilistic-reasoning and theory-of-mind (ToM) tasks. No study to date has examined the relations between these 3 reasoning anomalies in the same individuals so as to evaluate their functional independence and potentially inform theories of delusion formation. We did so in 35 schizophrenic patients with a history of delusions, 30 of whom were currently deluded, and 34 healthy controls. Compared with healthy controls, patients showed (a) a jumping-to-conclusions bias and a bias to overadjust when confronted with a change of evidence on probabilistic-reasoning tasks, (b) an excessive externalizing attributional bias, and (c) performance deficits on 3 ToM tasks. Probabilistic-reasoning and ToM measures correlated, while attributional-bias scores were independent of other task measures. A general proneness to delusional ideation correlated with probabilistic-reasoning and ToM measures, while externalizing bias was unrelated to the study measures of delusional ideation. Personalizing bias associated specifically with paranoia across the clinical and nonclinical participants. Findings are consistent with a common underlying mechanism in schizophrenia which contributes to the anomalies on probabilistic-reasoning and ToM tasks associated with delusions. We speculate that this mechanism is impairment of the normal capacity to inhibit "perceived reality" (the evidence of our senses), a capacity that evolved as part of the "social brain" to facilitate intersubjective communication within a shared reality.

Two approaches dominate research on the lack of awareness of illness that characterizes schizophrenia. The "deficit" approach uses standardized neuropsychological batteries to identify the neural underpinnings of intact insight; the "nondeficit" approach investigates the psychological defense mechanisms that motivate denial of illness. We adopt, instead, a cognitive neuropsychological approach to model the cognitive processes which underpin insight and which might be either damaged (because of neuropathology) or not used (because of motivational forces). We conceive of these processes in terms of a metacognitive capacity "to see ourselves as others see us." We predict that a general difficulty with adopting other mental perspectives (with "seeing the world as others do"), indexed by performance deficits on theory of mind (ToM) tasks, will impair insight in schizophrenia. Thirty schizophrenic patients (also assessed for insight) and 26 healthy controls completed a battery of ToM tasks which varied presentation modality, response mode and instruction type (picture sequencing, joke appreciation and story comprehension tasks). While patients performed more poorly than controls on all ToM tasks, impairment in patients was not concordant across tasks. ToM scores from the picture sequencing and joke appreciation tasks, and not the story comprehension task, intercorrelated significantly in patients and predicted insight. Findings support the view that insight relies upon a cognitive capacity to adopt the other perspective, which, if intact, contributes to the metacognitive capacity to reflect upon "one's own" mental health from the other perspective. Findings also suggest that the nature of perspective-taking difficulty which disrupts insight in schizophrenia is best revealed using ToM tasks with "indirect" instructions.

Background: Despite the popularity of inner-speech theories of auditory verbal hallucinations (AVHs), little is known about the phenomenological qualities of inner speech in patients with schizophrenia who experience AVHs (Sz-AVHs), or how this compares to inner speech in the non-voice-hearing general population., Method: We asked Sz-AVHs (n=29) and a non-voice-hearing general population sample (n=42) a series of questions about their experiences of hearing voices, if present, and their inner speech., Results: The inner speech reported by patients and controls was found to be almost identical in all respects. Furthermore, phenomenological qualities of AVHs (e.g. second- or third-person voices) did not relate to corresponding qualities in inner speech., Conclusions: No discernable differences were found between the inner speech reported by Sz-AVHs and healthy controls. Implications for inner-speech theories of AVHs are discussed.

Previous inconsistent findings concerning a link between working memory dysfunction and negative aspects of non-clinical schizotypy have been interpreted to cast doubt on the continuity model of 'negative psychosis-proneness'. This study employed the Letter-Number-Sequencing (LNS) task and the Trail-Making Test to assess more demanding, executive working memory. A secondary concern was to rule out possible mediating effects of familial schizophrenia. It was hypothesised that executive working memory impairment would be associated primarily with negative rather than positive schizotypy even in the absence of familial schizophrenia. Matrix reasoning controlled for IQ. In 87 university-student participants with no known family history of schizophrenia, lower LNS scores were associated with higher levels of negative and positive schizotypy traits. Counter to expectations, matrix reasoning scores were also associated with schizotypy, primarily the cognitive/perceptual traits. Results were similar when participants with a known family history of schizophrenia (10) were included (N=97). Findings support the view that impairment of executive working memory (indexed by LNS) is a reliable cognitive marker for negative (and perhaps also positive) schizophrenia vulnerability, independent of familial schizophrenia, and provide the first indication that some facets of IQ (e.g. inductive reasoning) might also be compromised in non-clinical schizotypy.

Introduction: The present study was designed to replicate and extend the findings of Bentall and Swarbrick (2003). It was hypothesised that patients with a history of persecutory delusions would display higher need for closure and a more extreme jumping to conclusions bias than healthy control participants., Methods: Twenty-two patients with a history of persecutory delusions and nineteen healthy control participants were administered a probabilistic reasoning task, along with self-report measures of depression and need for closure., Results: The clinical group scored higher on need for closure than the controls, but showed no greater tendency to jump to conclusions. No relationship was found between need for closure and a jumping to conclusions bias., Conclusions: The results confirm an association between persecutory delusions and need for closure, yet suggest that persecutory delusions in an outpatient sample can be seen in the absence of a jumping to conclusions bias.

Numerous delusions have been studied which are highly specific and which can present in isolation in people whose beliefs are otherwise entirely unremarkable - "monothematic delusions" such as Capgras or Cotard delusions. We review such delusions and summarize our 2-factor theory of delusional belief which seeks to explain what causes these delusional beliefs to arise initially and what prevents them being rejected after they have arisen. Although these delusions can occur in the absence of other symptoms, they can also occur in the context of schizophrenia, when they are likely to be accompanied by other delusions and hallucinations. We propose that the 2-factor account of particular delusions like Capgras and Cotard still applies even when these delusions occur in the context of schizophrenia rather than occurring in isolation.

This study examined stimulus-driven and willed action in schizophrenic patients and healthy controls using an easy finger-tap task and a more demanding peg-placement task under unimanual, bimanual and dual-task conditions. Peg-placement externally cued by a metronome was also examined, as were practice effects. Patients with marked negative symptoms placed fewer pegs unimanually with and without practice and benefited most from metronome-cueing. Under dual-task conditions, when the participants placed pegs while concurrently finger-tapping, finger-tapping slowed down relative to unimanual scores in patients more than controls. Number of pegs placed also dropped off in controls and the patients with fewer negative symptoms. However, patients with more severe negative symptoms placed just as many pegs, and sometimes more, in the dual-task, compared to the unimanual, condition. These patients appeared to be using their finger-tapping just like an 'external' pacing-stimulus for peg-placement, thus rendering their peg-placement more stimulus-driven than willed. In contrast, patients with fewer negative symptoms and controls tried to self-generate maximal performance on both finger-tapping and peg-placement, with deleterious effects on both tasks. That the patients with marked negative symptoms performed best when their actions were more stimulus-driven than willed strengthens the case that negative schizophrenic symptoms reflect a disorder of willed action.

Introduction: Schizophrenia and autism are clinically distinct yet both disorders are characterised by theory of mind (ToM) deficits. Autistic individuals fail to appreciate false beliefs, yet understand the causal connections between behavioural events and simple emotions. Findings of this type have promoted the view that ToM deficits in autism reflect a domain-specific difficulty with appreciating the representational nature of epistemic mental states (i.e., beliefs and intentions and not emotions). This study examines whether the same holds true for schizophrenia., Methods: A picture-sequencing task assessed capacity to infer false beliefs in patients with schizophrenia and healthy controls. To assess emotion attribution, participants were shown cartoon strips of events likely to elicit strong emotional reactions in story characters. Characters' faces were blanked out. Participants were instructed to think about how the characters would be feeling in order to match up the cards depicting facial affect appropriately. Participants later named emotions depicted in facial affect cards., Results: Patients were as capable as controls of identifying cartoon facial expressions, yet had greater difficulties with: (a) attributing emotions based on circumstances; and (b) inferring false beliefs., Conclusions: Schizophrenia patients, unlike autistic individuals, suffer a domain-general difficulty with empathetic perspective-taking that affects equally their appreciation of other people's beliefs, percepts, and emotions.

The ability to detect the direction of another person's gaze and to shift our own attention reflexively in the same direction facilitates the sharing of attention with other people. Such sharing of attention would seem critical for the maintenance of normal social cognition. Social cognition is severely impaired in people with schizophrenia. So, we used spatial cuing paradigms to investigate reflexive (Experiment 1) and controlled (Experiment 2) attentional orienting triggered by gaze in schizophrenia. In Experiment 1, 30 patients and 24 controls detected targets appearing right or left of a central image of a head turned right, left, or straight-ahead. These gaze-cues were non-predictive. Patients, but not controls, showed a significant congruency advantage at 100 ms SOA. The congruency advantage was similar in patients and controls at 300-800 ms SOA. In Experiment 2, 20 patients and 24 controls detected targets 300-800 ms after a central gaze-cue that pointed away from the target on 80% of trials. Controls, but not patients, were able to reverse the reflexive congruency advantage at 800 ms SOA. This study provides the first evidence that people with schizophrenia show abnormally sensitive gaze-triggered reflexive orienting. Findings are discussed in light of recent neuroimaging work investigating the neural basis of social orienting and social cognition.

Background: Disturbed speech in schizophrenia may reflect pragmatic deficits of expressive language. Pragmatic comprehension deficits also occur in schizophrenia. This study investigated whether poor 'mind-reading' (i.e. a general difficulty with inferring and monitoring other people's thoughts) causes pragmatic language impairments of both expression and comprehension in patients with schizophrenia., Method: Mind-reading (or theory of mind) was tested in patients with schizophrenia and in healthy controls using a false-belief picture-sequencing task. Pragmatic comprehension skills were assessed using a test of non-literal speech interpretation. Clinical ratings of formal thought disorder (FTD) indexed the expressive language deficits of patients. To control for possible contributory effects of executive dysfunction, inhibitory control was tested using capture picture-sequences and executive-planning was tested using the Tower of London task., Results: False-belief picture-sequencing, understanding of irony and understanding of metaphors were all selectively impaired in the patients. Poor mind-reading (indexed by high error rate in sequencing false-belief stories) was associated with poor understanding of irony, but was unrelated to poor understanding of metaphors. Whereas poor appreciation of irony and poor mind-reading were associated with high ratings of positive formal thought disorder, high ratings of negative formal thought disorder were associated with poor understanding of metaphors and executive dysfunction., Conclusions: Whereas poor mind-reading may contribute to positive aspects of formal thought disorder and impaired appreciation of irony in patients with schizophrenia; negative features of formal thought disorder and poor understanding of metaphors appear better explained by abnormal semantics. Overall, the findings of this study support the view that the functional basis of formal thought disorder in schizophrenia is not unitary.