Positive and negative schizotypy reflect distinct patterns of subclinical traits in the general population associated with neurodevelopmental and schizophrenia-spectrum pathologies. Yet, a comprehensive characterization of the unique and shared neuroanatomical signatures of these schizotypy dimensions is lacking. Leveraging 3D brain MRI data from 2730 unmedicated healthy individuals, we identified neuroanatomical profiles of positive and negative schizotypy and systematically compared them with disorder-specific, microarchitectural, neurotransmitter-level, and connectome measures. Positive and negative schizotypy were associated with distinct cortical signatures, of predominantly thinner frontal and thicker paralimbic cortical areas, respectively. These cortical signatures of positive and negative schizotypy were differentially linked to brain-wide cortical patterns of schizophrenia-spectrum (clinical high-risk for psychosis, schizophrenia) and neurodevelopmental conditions (ADHD, autism spectrum disorder and 22q11.2 deletion syndrome). Additionally, the positive and negative schizotypy-related cortical profiles mapped onto different local attributes of gene expression, cortical myelination, D1, and histamine receptor distributions. Network models further showed that positive and negative schizotypy cortical signatures were spatially associated with cortical hubs, suggesting that highly interconnected regions are more vulnerable to the morphological differences associated with both schizotypy dimensions. Finally, predominantly sensorimotor-to-association and paralimbic areas emerged as epicenters with connectivity profiles significantly linked to the schizotypy-related cortical patterns. Collectively, this study identified cortical signatures of positive and negative schizotypy traits that are embedded along multiple scales of cortical organization and neuropsychiatric pathologies. Our work yields novel insights into how neurobiology and brain architecture may guide neuroanatomical vulnerability and resilience to psychopathology in the general population.
[This corrects the article DOI: 10.3389/fpsyt.2024.1467141.].
Introduction We previously found that self-guided Virtual Reality Exposure Therapy (VRET) improved Public Speaking Anxiety (PSA) and reduced heartrate. Elevated heartrate characterises social anxiety and the self-guided VRET seemed to reduce heartrate. Thus, receiving continuous biofeedback about physiological arousal during the VRET could help socially anxious individuals to manage their anxiety. The present study aimed to determine whether biofeedback enhances the responsiveness of VRET.Methods Seventy-two individuals with high self-reported social anxiety were randomly allocated to VRET-plus-biofeedback (n=38; 25 completers) or VRET-alone (n=35; 25 completers). Three hour-long VRET sessions were delivered over two consecutive weeks. During each session, participants delivered a 20-minute public speech in front of a virtual audience.Results Participants in the VRET-plus-biofeedback group received biofeedback on heartrate and frontal alpha asymmetry (FAA) within the virtual environment and were asked to lower their arousal accordingly. Participants in both groups completed psychometric assessments of social anxiety after each session and at one-month follow-up. PSA improved by the end of treatment and overall social anxiety improved one month after the VRET across both groups. The VRET-plus-biofeedback group showed a steadier reduction in FAA in the first VRET session and a greater reduction in self-reported arousal across the two sessions than the VRET-alone group.Conclusion Biofeedback can steady physiological arousal and lower perceived arousal during exposure. The benefits of self-guided VRET for social anxiety are sustained one month after therapy.
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.
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.
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 asym-metry (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.
Altered electroencephalography (EEG) activity in schizotypal individuals is a powerful indicator of proneness towards psychosis. This alteration is beyond decreased alpha power often measured in resting state EEG. Multiscale fluctuation dispersion entropy (MFDE) measures the non-linear complexity of the fluctuations of EEGs and is a more effective approach compared to the traditional linear power spectral density (PSD) measures of EEG activity in patients with neurodegenerative disorders. In this study, we applied MFDE to EEG signals to distinguish high schizotypy (HS) and low schizotypy (LS) individuals. The study includes several trials from 29 participants psychometrically classified as HS (n=19) and LS (n=10). After preprocessing, MFDE was computed in frontal, parietal, central, temporal and occipital regions for each participant at multiple time scales. Statistical analysis and machine learning algorithms were used to calculate the differences in MFDE measures between the HS and LS groups. Our findings revealed significant differences in MFDE measures between LS and HS individuals in the delta frequency band (at time scale 100 ms). HS individuals exhibited increased complexity and irregularity compared to LS individuals in the delta frequency band particularly in the occipital region. Furthermore, the MFDE measures resulted in high accuracy (96.55%) in discriminating between HS and LS individuals and outperformed the models based on power spectrum, demonstrating the potential of MFDE as a neurophysiological marker for schizotypy traits. The increased non-linear fluctuation in delta frequency band in the occipital region of HS individuals implies the changes in cognitive functions, such as memory and attention, and has significant potential as a biomarker for schizotypy and proneness towards psychosis.
Rejection sensitivity (RS) is the expectation of being distanced from and excluded by others, and found to be positively associated with both schizotypal personality traits and aggression. Here, we propose different explanations for these associations. Specifically, we suggest that disorganisation and social anxiety explain RS in schizotypy, but anger and the need for reward from retaliation and mood repair explain RS in aggression. There is some support for our suggestions from recent studies showing neural activity and/or connectivity patterns during social rejection that indicate deficient emotional regulation and anxiety in schizotypy, but heightened social pain and retaliation in relation to aggression. Further research needs to firmly establish how RS, schizotypy and aggression might exist, or co-exist, at the behavioural and brain levels, and whether interventions that specifically target social anxiety, maladaptive emotion regulation, or promote prosocial behaviours could be employed to normalise RS in the context of schizotypy and/or aggression.
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.
Virtual-reality exposure therapy (VRET) is a novel intervention technique that allows individuals to experience anxiety evoking stimuli in a safe environment, to recognise specific triggers and gradually increase their exposure to perceived threats. Public-speaking anxiety (PSA) is very common 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 models for anxiety or stress detection are equally important, and multi-disciplinary expertise is required. In this work, we have explored a series of machine learning 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 the distress. Here, we discuss the means of effective selection of machine learning 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 many other domains of interest, where arousal detection is crucial.
This paper represents the outcome of a multidisciplinary discussion on what works, what does not, and what can be improved, in ongoing work on biobehavioral taxonomies and their biomarkers. The authors of this paper, representing a wide spectrum of biobehavioral disciplines (clinical, developmental, differential psychology, neurophysiology, endocrinology, psychiatry, neurochemistry, and neurosciences), have contributed more extensive opinions to the Theme Issue 'Neurobiology of temperament, personality and psychopathology: what's next?'. The authors identified 10 directions in international and multidisciplinary cooperation, and multiple insights for 'what is next' for each of these directions.
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.
EDITORIAL article Front. Virtual Real., 09 February 2022 | https://doi.org/10.3389/frvir.2022.853678
Expressed emotion (EE) is a rating of criticism, hostility, and emotional over-involvement from a carer towards a person experiencing mental distress. High EE denotes family stress and is associated with greater severity of substance use. Little is known about how EE is perceived by patients with a history of substance use disorder (SUD). The aim of the present study was to investigate perceived EE among substance users and its association with substance use, schizotypy, and depression. Ratings of arousal and relevance of auditory criticism and praise depicting EE, and self-report measures of schizotypy and depression were measured in patients with a recent history of SUD, patients with a recent history of SUD co-occurring with mental disorders (SUD + CMD), and non-clinical healthy control subjects. Group differences in ratings of criticism and praise were tested. The ratings were correlated against schizotypy and depression. Prediction of sensitivity to criticisms by a history of substance use was explored in the SUD groups. Compared to control subjects, individuals with a history of SUD rated criticism as less arousing and those with SUD + CMD rated criticism as more self-relevant. The rating of criticism was positively correlated with schizotypy and depression in the SUD group. Age of onset of substance use was a significant predictor of the arousal of criticism. History of SUD may affect perception of negative audio comments depicting family stress. This effect may be enhanced by high schizotypy traits and negative mental health status, and early age of onset of substance use.
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, p FDR = 0.02). The cortical thickness profile in schizotypy was positively correlated with cortical abnormalities in SZ ( r = 0.285, p spin = 0.024), but not BD ( r = 0.166, p spin = 0.205) or MDD ( r = −0.274, p spin = 0.073). The schizotypy-related subcortical volume pattern was negatively correlated with subcortical abnormalities in SZ (rho = −0.690, p spin = 0.006), BD (rho = −0.672, p spin = 0.009), and MDD (rho = −0.692, p spin = 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.
AbstractNeuroanatomical 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 3,004 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=.07, pFDR=.02). The cortical thickness profile in schizotypy was positively correlated with cortical abnormalities in SZ (r=.33, pspin=.01), but not BD (r=.19, pspin=.16) or MDD (r=-.22, pspin=.10). The schizotypy-related subcortical volume pattern was negatively correlated with subcortical abnormalities in SZ (rho=-.65, pspin=.01), BD (rho=-.63, pspin=.01), and MDD (rho=-.69, pspin=.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.
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.