Enhancing biofeedback-driven self-guided virtual reality exposure therapy through arousal detection from multimodal data using machine learning.

Virtual reality exposure therapy (VRET) is a novel intervention technique that allows individuals to experience anxiety-evoking stimuli in a safe environment, recognise specific triggers and gradually increase their exposure to perceived threats. Public-speaking anxiety (PSA) is a prevalent form of social anxiety, characterised by stressful arousal and anxiety generated when presenting to an audience. In self-guided VRET, participants can gradually increase their tolerance to exposure and reduce anxiety-induced arousal and PSA over time. However, creating such a VR environment and determining physiological indices of anxiety-induced arousal or distress is an open challenge. Environment modelling, character creation and animation, psychological state determination and the use of machine learning (ML) models for anxiety or stress detection are equally important, and multi-disciplinary expertise is required. In this work, we have explored a series of ML models with publicly available data sets (using electroencephalogram and heart rate variability) to predict arousal states. If we can detect anxiety-induced arousal, we can trigger calming activities to allow individuals to cope with and overcome distress. Here, we discuss the means of effective selection of ML models and parameters in arousal detection. We propose a pipeline to overcome the model selection problem with different parameter settings in the context of virtual reality exposure therapy. This pipeline can be extended to other domains of interest where arousal detection is crucial. Finally, we have implemented a biofeedback framework for VRET where we successfully provided feedback as a form of heart rate and brain laterality index from our acquired multimodal data for psychological intervention to overcome anxiety.

The relationships between expressed emotion, cortisol, and EEG alpha asymmetry.

Families can express high criticism, hostility and emotional over-involvement towards a person with or at risk of mental health problems. Perceiving such high expressed emotion (EE) can be a major psychological stressor for individuals, especially those at risk of mental health problems. To reveal the biological mechanisms underlying the effect of EE on health, this study investigated physiological response (salivary cortisol, frontal alpha asymmetry (FAA)) to verbal criticism and their relationship to anxiety and perceived EE. Using a repeated-measures design, healthy participants attended three testing sessions on non-consecutive days. On each day, participants listened to one of three types of auditory stimuli, namely criticism, neutral or praise, and Electroencephalography (EEG) and salivary cortisol were measured. Results showed a reduction in cortisol following criticism but there was no significant change in FAA. Post-criticism cortisol concentration negatively correlated with perceived EE after controlling for baseline mood. Our findings suggest that salivary cortisol change responds to criticism in non-clinical populations and this response might be largely driven by individual differences in the perception of criticism (e.g., arousal and relevance). Criticisms expressed by audio comments may not be explicitly perceived as an acute emotional stressor, and thus, physiological response to criticisms could be minimum.

Conceptualising mental illness among University students of African, Caribbean and similar ethnic heritage in the United Kingdom.

OBJECTIVE: Students of African, Caribbean and similar ethnicity (ACE) encounter unique mental health challenges within the Western higher education system, such as feeling constrained in social spaces and perceiving greater stigma about mental health. Students of ACE are also resilient to mental health problems, such as depression, when enduring social inequality. This study aimed to conceptualise mental illness and help-seeking behaviours among university students in the United Kingdom (UK) in the context of their identity as ACE. DESIGN: Six university students of ACE in the UK were interviewed about the meaning of mental illness, the influence of ACE culture on mental health and help-seeking by ACE students. Thematic analysis was applied from a socio-constructionist theoretical lens to interpret the interview transcripts. RESULTS: Five main themes emerged, namely 'Perceived meanings and attitudes toward mental health problems', 'Beliefs about the non-existence of mental health problem and its spiritual attributions', 'Family dynamics and the 'silencing' of mental health problems', 'Help-seeking for mental health among people of ACE' and 'Stigma and discriminatory responses to mental health issues'. Participants expressed that mental health is an imported concept that people from ACE communities tend to shy away from. A reluctance to discuss mental health problems arose over fear of rejection from families and fear of not being understood by a mental health professional from a different cultural background. CONCLUSION: University students of ACE and their families struggle to adopt the Western conceptualisation of mental health. Consequently, there is poor awareness of mental health issues and stigma of mental illness among university students of ACE which pose a barrier to help-seeking for mental health. The limited sample size constrains the ability to draw sound conclusions. Nonetheless, a culturally sensitive conceptualisation of mental health is needed to address poor help-seeking for mental health among people of ACE.

Tensor factorization approach for ERP-based assessment of schizotypy in a novel auditory oddball task on perceived family stress.

Objective. Schizotypy, a potential phenotype for schizophrenia, is a personality trait that depicts psychosis-like signs in the normal range of psychosis continuum. Family communication may affect the social functioning of people with schizotypy. Greater family stress, such as irritability, criticism and less praise, is perceived at a higher level of schizotypy. This study aims to determine the differences between people with high and low levels of schizotypy using electroencephalography (EEG) during criticism, praise and neutral comments. EEGs were recorded from 29 participants in the general community who varied from low schizotypy to high schizotypy (HS) during a novel emotional auditory oddball task.Approach. We consider the difference in event-related potential parameters, namely the amplitude and latency of P300 subcomponents (P3a and P3b), between pairs of target words (standard, positive, negative and neutral). A model based on tensor factorization is then proposed to detect these components from the EEG using the CANDECOMP/PARAFAC decomposition technique. Finally, we employ the mutual information estimation method to select influential features for classification.Main results.The highest classification accuracy, sensitivity, and specificity of 93.1%, 94.73%, and 90% are obtained via leave-one-out cross validation.Significance. This is the first attempt to investigate the identification of individuals with psychometrically-defined HS from brain responses that are specifically associated with perceiving family stress and schizotypy. By measuring these brain responses to social stress, we achieve the goal of improving the accuracy in detection of early episodes of psychosis.

Classification of Low and High Schizotypy Levels via Evaluation of Brain Connectivity.

Schizotypy is a latent cluster of personality traits that denote a vulnerability for schizophrenia or a type of spectrum disorder. The aim of the study is to investigate parametric effective brain connectivity features for classifying high versus low schizotypy (LS) status. Electroencephalography (EEG) signals are recorded from 13 high schizotypy (HS) and 11 LS participants during an emotional auditory odd-ball task. The brain connectivity signals for machine learning are taken after the settlement of event-related potentials. A multivariate autoregressive (MVAR)-based connectivity measure is estimated from the EEG signals using the directed transfer functions (DTFs) method. The values of DTF power in five standard frequency bands are used as features. The support vector machines (SVMs) revealed significant differences between HS and LS. The accuracy, specificity, and sensitivity of the results using SVM are as high as 89.21%, 90.3%, and 88.2%, respectively. Our results demonstrate that the effective brain connectivity in prefrontal/parietal and prefrontal/frontal brain regions considerably changes according to schizotypal status. These findings prove that the brain connectivity indices offer valuable biomarkers for detecting schizotypal personality. Further monitoring of the changes in DTF following the diagnosis of schizotypy may lead to the early identification of schizophrenia and other spectrum disorders.

Cortical and subcortical neuroanatomical signatures of schizotypy in 3004 individuals assessed in a worldwide ENIGMA study.

Neuroanatomical abnormalities have been reported along a continuum from at-risk stages, including high schizotypy, to early and chronic psychosis. However, a comprehensive neuroanatomical mapping of schizotypy remains to be established. The authors conducted the first large-scale meta-analyses of cortical and subcortical morphometric patterns of schizotypy in healthy individuals, and compared these patterns with neuroanatomical abnormalities observed in major psychiatric disorders. The sample comprised 3004 unmedicated healthy individuals (12-68 years, 46.5% male) from 29 cohorts of the worldwide ENIGMA Schizotypy working group. Cortical and subcortical effect size maps with schizotypy scores were generated using standardized methods. Pattern similarities were assessed between the schizotypy-related cortical and subcortical maps and effect size maps from comparisons of schizophrenia (SZ), bipolar disorder (BD) and major depression (MDD) patients with controls. Thicker right medial orbitofrontal/ventromedial prefrontal cortex (mOFC/vmPFC) was associated with higher schizotypy scores (r = 0.067, pFDR = 0.02). The cortical thickness profile in schizotypy was positively correlated with cortical abnormalities in SZ (r = 0.285, pspin = 0.024), but not BD (r = 0.166, pspin = 0.205) or MDD (r = -0.274, pspin = 0.073). The schizotypy-related subcortical volume pattern was negatively correlated with subcortical abnormalities in SZ (rho = -0.690, pspin = 0.006), BD (rho = -0.672, pspin = 0.009), and MDD (rho = -0.692, pspin = 0.004). Comprehensive mapping of schizotypy-related brain morphometry in the general population revealed a significant relationship between higher schizotypy and thicker mOFC/vmPFC, in the absence of confounding effects due to antipsychotic medication or disease chronicity. The cortical pattern similarity between schizotypy and schizophrenia yields new insights into a dimensional neurobiological continuity across the extended psychosis phenotype.

The Effectiveness of Self-Guided Virtual-Reality Exposure Therapy for Public-Speaking Anxiety.

Objectives: Self-guided virtual-reality exposure therapy (VRET) is a psychological intervention that enables a person to increase their own exposure to perceived threat. Public-speaking anxiety (PSA) is an anxiety-provoking social situation that is characterized by fear of negative evaluation from an audience. This pilot study aimed to determine whether self-guided VRET (1) increases exposure to PSA-specific virtual social threats, and (2) reduces anxiety, arousal, heartrate and PSA over repeated exposure. Methods: Thirty-two University students (27 completers) with high self-reported public-speaking anxiety attended 2 weekly self-guided VRET sessions. Each session involved the participant delivering a 20-min speech in a virtual classroom. Participants were able to increase their exposure to virtual social threat through the audience size, audience reaction, number of speech prompts, and their own salience in the virtual classroom at 4-min intervals. Participants' heartrates and self-reported anxiety and arousal were monitored during these intervals. Participants completed psychometric assessments after each session and 1 month later. Results: Participants increased their exposure to virtual social threat during each VRET session, which coincided with a reduction in heartrate and self-reported anxiety and arousal. Improvement in PSA occurred post-treatment and 1 month later. The in-session improvement in anxiety correlated with reductions in fear of negative evaluation post-treatment and 1 month later. Conclusions: Increased self-exposure to virtual social threat from self-guided VRET relieves anxiety and shows immediate reductions in subjective and physiological arousal during application, but also yields sustained improvement in PSA.

Pituitary volume in people with chronic schizophrenia: Clarifying the roles of serious violence and childhood maltreatment.

Aberrations in stress-linked hypothalamic-pituitary-adrenal axis function have been independently associated with schizophrenia, antisocial behaviour and childhood maltreatment. In this study, we examined pituitary volume (PV) in relation to childhood maltreatment (physical abuse, sexual abuse, neglect) in men (i) with schizophrenia and a history of serious violence (n = 13), (ii) with schizophrenia but without a history of serious violence (n = 15), (iii) with antisocial personality disorder (ASPD) and a history of serious violence (n = 13), and (iv) healthy participants without a history of violence (n = 15). All participants underwent whole-brain magnetic resonance imaging. Experiences of childhood maltreatment were rated based on interviews (for all), and case history and clinical/forensic records (for patients only). There was a trend for smaller PV, on average, in schizophrenia patients (regardless of a history of violence), compared to the healthy group and the ASPD group; other group differences in PV were non-significant. Sexual abuse ratings correlated negatively with PVs in ASPD participants, but no significant association between childhood maltreatment and PV was found in schizophrenia participants. Our findings are consistent with previous evidence of smaller-than-normal PV in chronic schizophrenia patients, and suggest that illness-related influences may mask the possible sexual abuse-smaller PV association, seen here in ASPD, in this population.

Mild-to-moderate schizotypal traits relate to physiological arousal from social stress.

Schizotypy denotes psychosis-like experiences, such as perceptual aberration, magical ideation, and social anxiety. Altered physiological arousal from social stress is found in people with high schizotypal traits. Two experiments aimed to determine the relationship of schizotypy to physiological arousal from social stress. Experiment 1 tested the hypotheses that heart rate from social stress would be greater in high, than mild-to-moderate, schizotypal traits, and disorganized schizotypy would explain this effect because of distress from disorganisation. Experiment 1 tested social stress in 16 participants with high schizotypal traits and 10 participants with mild-to-moderate schizotypal traits. The social stress test consisted of a public speech and an informal discussion with strangers. The high schizotypal group had a higher heart rate than the mild-to-moderate schizotypal group during the informal discussion with strangers, but not during the public speech. Disorganized schizotypy accounted for this group difference. Experiment 2 tested the hypothesis that mild-to-moderate schizotypal traits would have a linear relationship with physiological arousal from social stress. Experiment 2 tested 24 participants with mild-to-moderate schizotypal traits performing the abovementioned social stress test while their heart rate and skin conductance responses were measured. Mild-to-moderate schizotypal traits had a linear relationship with physiological arousal during the discussion with strangers. Distress in disorganized schizotypy may explain the heightened arousal from close social interaction with strangers in high schizotypy than mild-to-moderate schizotypy. Mild-to-moderate schizotypal traits may have a linear relationship with HR during close social interaction because of difficulty with acclimatizing to the social interaction.

The path from schizotypy to depression and aggression and the role of family stress.

BACKGROUND: Schizotypy is a multidimensional construct that is linked to the vulnerability for psychosis. Positive schizotypy includes having paranormal beliefs. Negative schizotypy includes social anhedonia. Disorganized schizotypy includes social anxiety and communication disorder. Schizotypy relates to depression and aggression. Family stress from high expressed emotion (EE; a rating of criticism, hostility, and emotional overinvolvement in a close relative toward a person showing signs of mental disorder) may mediate the link between schizotypy, depression and aggression. This study tested, using path analyses, the hypotheses that schizotypy predicts depression and aggression through high perceived EE as criticism and irritability (hypothesis 1) and praise and intrusiveness in a close relative (hypothesis 2). METHODS: One hundred and four healthy participants listened to and rated the self-relevance of standard criticism and standard praise that denote EE. Participants rated their level of schizotypy, depression, aggression, and perceived EE in self-report questionnaires. Two path models tested the hypotheses. RESULTS: Disorganized schizotypy, more than positive schizotypy, predicted the path to depression and aggression when perceived criticism and perceived EE-irritability were mediators. Disorganised schizotypy, more than negative schizotypy, predicted the path to depression and aggression when perceived praise and perceived EE-intrusiveness were mediators. CONCLUSIONS: Greater perceived criticism and less perceived praise in family communication explain the path from disorganized schizotypy (more so than positive or negative schizotypy) to depression and aggression. These findings indicate a need to consider the thought disorder-EE link as a potential contributor to depression and aggression in people with schizophrenia.

Neural responses to criticism and praise vary with schizotypy and perceived emotional support.

Schizotypy is a latent organisation of a cluster of personality styles, such as magical thinking, disorganisation and anhedonia, which are in the normal range of the psychosis continuum. Schizotypy relates to an increased likelihood of perceiving expressed emotion (EE). EE is characterised by criticism, rejection, and emotional over-involvement and less warmth from a close relative. Neuroimaging studies have found normal frontal lobe activation to EE-criticism in people with high schizotypy. Alternatively, electroencephalography measures emotion processing, such as frontal theta power and occipital alpha power. Frontal theta power responds to cognitive and affective processes and occipital alpha power denotes less consciousness and emotional attention. This study aimed to determine the relation of these electroencephalography responses during criticism and praise to perceived emotional support. Participants (n = 32) representing the full (low-to-high) range of positive schizotypy listened to and rated the self-relevance of EE-like criticism and praise and affectively neutral comments while undergoing electroencephalography. Participants completed self-report measures of schizotypy, depression and anxiety. A subset of those with a high positive schizotypy score (n = 22) completed a measure of perceived EE - lack of emotional support. Higher perceived EE - lack of emotional support correlated with lower frontal theta power and lower occipital alpha power during criticism and praise in schizotypal participants. The findings suggest that these neural responses may relate to less perceived emotional support in people with high schizotypy, of which a reduction of frontal theta power denotes less emotional arousal and lower occipital alpha power denotes more alertness to emotional information may relate to less perceived emotional support in people with high schizotypy.

Deciphering reward-based decision-making in schizophrenia: A meta-analysis and behavioral modeling of the Iowa Gambling Task.

Background: Patients with schizophrenia (SZP) have been reported to exhibit impairments in reward-based decision-making, but results are heterogeneous with multiple potential confounds such as age, intelligence level, clinical symptoms or medication, making it difficult to evaluate the robustness of these impairments. Methods: We conducted a meta-analysis of studies comparing the performance of SZP and healthy controls (HC) in the Iowa Gambling Task (IGT) as well as comprehensive analyses based on subject-level data (n = 303 SZP, n = 188 HC) to investigate reward-based decision-making in SZP. To quantify differences in the influence of individual deck features (immediate gain, gain frequency, net loss) between SZP and HC, we additionally employed a least-squares model. Results: SZP showed statistically significant suboptimal decisions as indicated by disadvantageous deck choices (d from 0.51 to −0.62) and lower net scores (d from −0.35 to −1.03) in a meta-analysis of k = 29 samples (n = 1127 SZP, n = 1149 HC) and these results were confirmed in a complementary subject-level analysis. Moreover, decision-making in SZP was characterized by a relative overweighting of immediate gain and net losses and an underweighting of gain frequency. Moderator analyses revealed that in part, decision-making in the IGT was moderated by intelligence level, medication and general symptom scores. Conclusion: Our results indicate robust impairments in reward-based decision-making in SZP and suggest that decreased cognitive resources, such as working memory, may contribute to these alterations.

Sensitivity to criticism and praise predicts schizotypy in the non-clinical population: The role of affect and perceived expressed emotion.

BACKGROUND: Schizotypy represents a cluster of personality traits consisting of magical beliefs, perceptual aberrations, disorganisation, and anhedonia. Schizotypy denotes a vulnerability for psychosis, one reason being psychosocial stress. High expressed emotion (EE), a rating of high criticism, hostility, and emotional over-involvement from a close relative, denotes psychosocial stress and vulnerability to psychosis, and is associated with schizotypy. This study aimed to decipher the relationship of schizotypy to perceived criticism and perceived praise in terms of affect and perceived EE. METHODS: Ninety-eight healthy participants listened to short audio-clips containing criticism, praise, and neutral comments from a stranger, and evaluated them in terms of the comments' arousal and personal relevance. Participants also answered self-report questionnaires of schizotypy, depression, mood, and perceived EE. Correlational analyses tested the relationship between schizotypy and the evaluations of criticism and praise. Mediation analyses then tested whether depression, positive mood, and perceived EE explained these relationships. RESULTS: Greater relevance of standard criticism correlated with higher positive schizotypy. This association was fully mediated by high depression and perceived irritability from a close relative. Lower relevance of standard praise correlated with higher cognitive disorganisation (another schizotypal trait). This relationship was partially mediated by low positive mood and high perceived intrusiveness from a close relative. CONCLUSION: Greater perceived criticism and lower perceived praise predict schizotypy in the healthy population. Affect and interpersonal sensitivity towards a close relative explain these relationships, such that depression increases perceived criticism, and positive mood increases perceived praise. Perceived EE defines the interpersonal nature of schizotypy.

Schizotypal traits and their relation to rejection sensitivity in the general population: Their mediation by quality of life, agreeableness and neuroticism.

Schizotypal traits are a cluster of personality styles suggesting a potential liability for schizophrenia-spectrum disorders. Interpersonal schizotypal traits include cognitive disorganisation which consists of social anxiety, and introvertive anhedonia which consists of a lack of pleasure in social activities. Rejection sensitivity is evident all along this continuum. This study aimed to determine whether psychosocial quality of life (QOL), neuroticism and agreeableness mediates the relation between schizotypy and rejection sensitivity. Three hundred and eighteen participants from a predominantly University student population completed an online survey measuring schizotypy, rejection sensitivity, quality of life, and the five-factor personality traits. A regression analysis determined the prediction of rejection sensitivity by schizotypy, quality of life, and the five personality traits. Analyses examined the mediation of the relation between interpersonal schizotypy and rejection sensitivity by psychological QOL, social QOL, neuroticism, and agreeableness. Cognitive disorganisation and introvertive anhedonia predicted greater rejection sensitivity, which in turn were mediated by psychological QOL, social QOL, neuroticism, and agreeableness. The findings show that interpersonal schizotypy relates to greater rejection sensitivity. Psychosocial factors that lower one's ability to have positive feelings, trusting relationships, and prosocial behaviour, and personality traits that increase worrying mediate this association.

Pituitary volume reduction in schizophrenia following cognitive behavioural therapy.

Cognitive behavioural therapy (CBT) for psychosis (CBTp) aims to lower the stress of psychotic symptoms. Given that the pituitary is involved in stress regulation, CBT-led stress reduction may be accompanied by a change in pituitary volume. This study aimed to determine whether CBTp reduces pituitary volume in schizophrenia. The relation between pre-therapy memory and CBTp-led pituitary volume change was also examined given that poor memory relates to a blunted cortisol awakening response, denoting impaired stress response, in schizophrenia. Pituitary volume was measured at baseline in 40 schizophrenia or schizoaffective disorder patients and 30 healthy participants before therapy. Pituitary volume was measured again 6-9months after patients had either received CBTp in addition to standard care (CBTp+SC, n=24), or continued with standard care alone (SC, n=16). CBTp+SC and SC groups were compared on pituitary volume change from baseline to follow-up. Pre-therapy memory performance (Hopkins Verbal Learning and Wechsler Memory Scale - Logical memory) was correlated with baseline-to-follow-up pituitary volume change. Pituitary volume reduced over time in CBTp+SC patients. Additionally, pre-therapy verbal learning correlated more strongly with longitudinal pituitary volume reduction in the CBTp+SC group than the SC group. To conclude, CBTp reduces pituitary volume in schizophrenia most likely by enhancing stress regulation and lowering the distress due to psychotic symptoms.

The relation between schizotypy and early attention to rejecting interactions: The influence of neuroticism.

OBJECTIVES: Schizotypy relates to rejection sensitivity (anxiety reflecting an expectancy of social exclusion) and neuroticism (excessive evaluation of negative emotions). Positive schizotypy (e.g., perceptual aberrations and odd beliefs) and negative schizotypy (e.g., social and physical anhedonia) could relate to altered attention to rejection because of neuroticism. METHODS: Forty-one healthy individuals were assessed on positive and negative schizotypy and neuroticism, and event-related potentials during rejecting, accepting and neutral scenes. Participants were categorised into high, moderate and low neuroticism groups. Using temporo-spatial principal components analyses, P200 (peak latency = 290 ms) and P300 amplitudes (peak latency = 390 ms) were measured, reflecting mobilisation of attention and early attention, respectively. RESULTS: Scalp-level and cortical source analysis revealed elevated fronto-parietal N300/P300 amplitude and P200-related dorsal anterior cingulate current density during rejection than acceptance/neutral scenes. Positive schizotypy related inversely to parietal P200 amplitude during rejection. Negative schizotypy related positively to P200 middle occipital current density. Negative schizotypy related positively to parietal P300, where the association was stronger in high and moderate, than low, neuroticism groups. CONCLUSIONS: Positive and negative schizotypy relate divergently to attention to rejection. Positive schizotypy attenuates, but negative schizotypy increases rejection-related mobilisation of attention. Negative schizotypy increases early attention to rejection partly due to elevated neuroticism.

Orbitofrontal cortex, emotional decision-making and response to cognitive behavioural therapy for psychosis.

Grey matter volume (GMV) in the orbitofrontal cortex (OFC) may relate to better response to cognitive behavioural therapy for psychosis (CBTp) because of the region׳s role in emotional decision-making and cognitive flexibility. This study aimed to determine the relation between pre-therapy OFC GMV or asymmetry, emotional decision-making and CBTp responsiveness. Emotional decision-making was measured by the Iowa Gambling task (IGT). Thirty patients received CBTp+standard care (CBTp+SC; 25 completers) for 6-8 months. All patients (before receiving CBTp) and 25 healthy participants underwent structural magnetic resonance imaging. Patients׳ symptoms were assessed before and after therapy. Pre-therapy OFC GMV was measured using a region-of-interest approach, and IGT performance was measured as overall learning, attention to reward, memory for past outcomes and choice consistency. Both these measures, were comparable between patient and healthy groups. In the CBTp+SC group, greater OFC GMV correlated with positive symptom improvement, specifically hallucinations and persecution. Greater rightward OFC asymmetry correlated with improvement in several negative and general psychopathology symptoms. Greater left OFC GMV was associated with lower IGT attention to reward. The findings suggest that greater OFC volume and rightward asymmetry, which maintain the OFC׳s function in emotional decision-making and cognitive flexibility, are beneficial for CBTp responsiveness.

Greater positive schizotypy relates to reduced N100 activity during rejection scenes.

Social anxiety due to rejection sensitivity (RS) exacerbates psychosis-like experiences in the general population. While reduced dorsal anterior cingulate cortex (dACC) activity during social rejection in high schizotypy has suggested self-distancing from rejection, earlier stages of mental processing such as feature encoding could also contribute to psychosis-like experiences. This study aimed to determine the stage of mental processing of social rejection that relates to positive schizotypy. Forty-one healthy participants were assessed for schizotypy and RS. Event-related potential amplitudes (ERPs) were measured at frontal, temporal and parieto-occipital sites and their cortical sources (dACC, temporal pole and lingual gyrus) at early (N100) and late (P300 and late slow wave, LSW) timeframes during rejection, acceptance and neutral scenes. ERPs were compared between social interaction types. Correlations were performed between positive schizotypy (defined as the presence of perceptual aberrations, hallucinatory experiences and magical thinking), RS and ERPs during rejection. Amplitude was greater during rejection than acceptance or neutral conditions at the dACC-P300, parieto-occipital-P300, dACC-LSW and frontal-LSW. RS correlated positively with positive schizotypy. Reduced dACC N100 activity during rejection correlated with greater positive schizotypy and RS. Reduced dACC N100 activity and greater RS independently predicted positive schizotypy. An N100 deficit that indicates reduced feature encoding of rejection scenes increases with greater positive schizotypy and RS. Higher RS shows that a greater tendency to misattribute ambiguous social situations as rejecting also increases with positive schizotypy. These two processes, namely primary bottom-up sensory processing and secondary misattribution of rejection, combine to increase psychosis-like experiences.

How do incorrect results change the processing of arithmetic information? Evidence from a divided visual field experiment.

Despite several recent important developments in understanding numerical processing of both isolated numbers and numbers in the context of arithmetic equations, the relative impact of congruency on high-level compared to low-level processing remains unclear. The current study investigated hemispheric differences in the processing of arithmetic material, as a function of semantic and perceptual congruency, using a delayed answer verification task and divided visual field paradigm. A total of 37 participants (22 females and 15 males, mean age 30.06, SD 9.78) were presented unilaterally or bilaterally with equation results that were either correct or incorrect and had a consistent or inconsistent numerical notation. Statistical analyses showed no visual field differences in a notation consistency task, whereas when judgements had to be made on mathematical accuracy there was a right visual field advantage for incorrect equations that were notation consistent. These results reveal a clear differential processing of arithmetic information by the two cerebral hemispheres with a special emphasis on erroneous calculations. Faced with incorrect results and with a consistent numerical notation, the left hemisphere outperforms its right counterpart in making mathematical accuracy decisions.

Lower anterior cingulate volume in seriously violent men with antisocial personality disorder or schizophrenia and a history of childhood abuse.

OBJECTIVE: Antisocial personality disorder (ASPD) and schizophrenia, as well as childhood abuse, are associated with violent behaviour and show marked volumetric reduction in the anterior cingulate (AC), a brain region implicated in regulation of violence through its involvement in decision making, empathy, impulse control, and emotion regulation. The present study examined, for the first time to the authors' knowledge, the grey matter volume of the AC in relation to seriously violent behaviour and childhood psychosocial deprivation (including physical and sexual abuse) in the context of a mental disorder (schizophrenia or ASPD). METHODS: Fifty-seven men [14 with ASPD and a history of serious violence; 13 with schizophrenia and a history of serious violence (VSZ); 15 with schizophrenia without a violence history (SZ); 15 nonviolent healthy participants] underwent whole-brain magnetic resonance imaging and were rated on the presence of physical abuse, sexual abuse, neglect, extreme poverty, foster home placement, criminal parent, severe family conflict, and broken home (collectively 'psychosocial deprivation'). Stereological volumetric ratings of the AC were examined for group differences and their association with childhood psychosocial deprivation. RESULTS: A higher proportion of ASPD and VSZ patients had suffered psychosocial deprivation as children, in particular severe physical abuse, relative to SZ patients and healthy participants. ASPD and VSZ, but not SZ, patients had significantly lower AC volume relative to healthy participants. AC volumes correlated negatively with (total) psychosocial deprivation as well as physical and sexual abuse ratings. Group differences in AC volume became nonsignificant when psychosocial deprivation ratings were covaried for. CONCLUSIONS: Violent mentally disordered individuals with ASPD or schizophrenia suffer from a significant AC volume loss and this deficit, at least in part, is explained by their histories of stressful childhood experiences. Current and future therapies aiming to reduce violence in such populations would benefit by attending to biological (and other) correlates of childhood abuse.