Exploring the effects of family and life events on genetic and environmental architecture of schizotypal and hypomanic dimensions: Insights from a twin study

BACKGROUND

Strategies of prevention for psychiatric disorders need a deep understanding of the aetiological factors involved in the psychopathological processes. Our twin study aims at disentangling the contributions of genes and environment to schizotypal and hypomanic dimensions, considering the role of stressful life events (LEs) and the quality of family relationships.

METHODS

The Magical Ideation Scale (MIS) and Perceptual Aberration Scale (PAS) were used to assess positive schizotypy, while Hypomanic Personality Scale (HPS) and its sub-scales were used to investigate proneness to affective disorders. 268 twins (54.5 % female; aged 18.0 ± 6.68) were included. Participants filled out a questionnaire on LEs and their parents provided an evaluation of intra-family relationship (Relationship Quality Index, RQI). Classic univariate twin models for quantitative traits were fitted for scales, and the effects of covariates (LEs and RQI) were assessed.

RESULTS

For MIS, HPS and its sub-scales, significant common and unique environmental effects were detected, with genetic factors affecting only HPS Social Vitality sub-scale. Unique environment was the only source of variance of PAS score. The number of recent LEs influenced MIS and PAS models, while RQI score affected MIS model.

LIMITATIONS

The main limitation of the study is the small sample size, which reduces statistical power and may potentially lead to an underestimation of heritability. Additionally, the cross-sectional design limits the possibility to draw causal considerations.

CONCLUSIONS

Findings provide preliminary evidence for a significant environmental role in modulating states of vulnerability. Moreover, the expression of positive schizotypy resulted influenced by recent stressors and intra-family relationships.

Association of Positive, Negative, and Disorganized Schizotypy With the Temporal Dynamics of Schizotypic Experiences in Daily Life

BACKGROUND AND HYPOTHESIS

Schizotypy is a useful and unifying construct for examining the etiology, development, and expression of schizophrenia-spectrum psychopathology. The positive, negative, and disorganized schizotypy dimensions are associated with distinct patterns of schizophrenia-spectrum symptoms and impairment. Furthermore, they are differentiated by mean levels of psychotic-like, suspicious, negative, and disorganized schizotypic experiences in daily life, and by temporal dynamics of affect. The schizotypy dimensions were thus hypothesized to be differentiated by the temporal dynamics of schizotypic experiences in daily life.

STUDY DESIGN

The present study employed experience sampling methodology in a large nonclinically ascertained sample (n = 693) to examine the associations of multidimensional schizotypy with psychotic-like, suspicious, negative, and disorganized schizotypic experiences in daily life, as well as with their temporal dynamics (variability, reactivity, inertia, and instability).

STUDY RESULTS

We replicated the mean-level associations between multidimensional schizotypy and schizotypic experiences in daily life. Furthermore, positive, negative, and disorganized schizotypy demonstrated hypothesized, differential patterns of temporal dynamics of schizotypic experiences. Disorganized schizotypy demonstrated the most robust associations, including intensity, variability, and inertia of disorganized schizotypic experiences. Disorganized schizotypy also moderated reactivity of psychotic-like and disorganized schizotypic experiences following previously reported stress. Positive schizotypy was associated with intensity and variability of psychotic-like experiences. Negative schizotypy was associated with intensity and variability of negative schizotypic experiences.

CONCLUSIONS

The findings indicate that schizotypy dimensions can be differentiated by both mean levels and temporal patterns of psychotic-like, suspicious, negative, and disorganized schizotypic experiences in daily life, with disorganized schizotypy uniquely characterized by stress reactivity.

Neuropsychology and Neurobiology of Negative Schizotypy: A Selective Review

Schizotypy refers to a latent personality organization that reflects liability to schizophrenia. Because schizotypy is a multidimensional construct, people with schizotypy vary in behavioral and neurobiological features. In this article, we selectively review the neuropsychological and neurobiological profiles of people with schizotypy, with a focus on negative schizotypy. Empirical evidence is presented for alterations of neuropsychological performance in negative schizotypy. We also cover the Research Domain Criteria domains of positive valence, social process, and sensorimotor systems. Moreover, we systematically summarize the neurobiological correlates of negative schizotypy at the structural, resting-state, and task-based neural levels, as well as the neurochemical level. The convergence and inconsistency of the evidence are critically reviewed. Regarding theoretical and clinical implications, we argue that negative schizotypy represents a useful organizational framework for studying neuropsychology and neurobiology across different psychiatric disorders.

The Future-oriented Repetitive Thought (FoRT) scale: Validation in Chinese samples and application in the schizophrenia spectrum

BACKGROUND

Repetitive thoughts are usually associated with psychopathology. The Future-oriented Repetitive Thought (FoRT) Scale is a measure designed to capture frequency of repetitive thought about positive and negative future events. However, the validity of the scale in Chinese population and its application in the schizophrenia spectrum have not been examined.

METHODS

The current study aimed to examine the psychometric properties of the Chinese version of the FoRT scale and to apply it to the schizophrenia spectrum. In Study 1, three samples (total N = 1875) of university students were recruited for exploratory factor analysis, confirmatory factor analysis, and validity test, respectively. In Study 2, we identified subsamples with high schizotypal traits (N = 89) and low schizotypal traits (N = 89), and recruited 36 inpatients with schizophrenia and 41 matched healthy controls.

RESULTS

The three-factor (pessimistic repetitive future thinking, repetitive thinking about future goals, and positive indulging about the future) structure of the FoRT scale with one item deleted, fitted the Chinese samples. And the scale could distinguish patients with schizophrenia and individuals with high schizotypal traits from controls.

CONCLUSION

These findings support that the Chinese version of the FoRT scale is a valid tool and provide evidence for the potential applications in the schizophrenia spectrum.

Taking the edge off: a feasibility randomized controlled trial of an online mindfulness-based intervention to reduce suspiciousness/paranoia in high positive schizotypy

Positive schizotypy can uniquely predict the development of psychosis with suspiciousness/paranoia having emerged as a key risk factor, pointing to significant worth in reducing this aspect in individuals with high positive schizotypy. Reduced paranoia in the general population following brief online mindfulness training has been previously reported. This study investigated the feasibility of a 40-day online mindfulness-based intervention (MBI) (n = 12) in the individuals with high positive schizotypy characterized by high suspiciousness/paranoia and to estimate its effect on paranoia as compared with an active control condition using reflective journaling (n = 12). The outcome measures were self-reported trait and VR-induced state paranoia, completed at baseline, after 10 days and post-intervention. The feasibility criteria included retention, adherence, engagement, and acceptability. There was 100% retention, excellent adherence to content and engagement, with an average MBI session completion rate of 91%. Acceptability, indexed by a self-rated motivation to continue practice post-intervention, was also high. No MBI effect on trait paranoia was observed; however, the MBI group showed a reduction in the VR-induced state paranoia with a medium-to-large effect (d = 0.63). The findings support conducting larger-scale randomized controlled trials to evaluate the effects of online MBIs on reducing suspiciousness/paranoia to mitigate psychosis risk in individuals with high positive schizotypy. Clinical Trial Registration:https://www.isrctn.com/, identifier ISRCTN78697391.

Social Activity in Schizotypy: Measuring Frequency and Enjoyment of Social Events

Improving social functioning deficits-a core characteristic of schizophrenia-spectrum disorders-is often listed by patients as a key recovery goal. Evidence suggests that social deficits also extend to people with schizotypy, a group at heightened risk for psychotic and other psychopathological disorders. One challenge of social functioning research in schizotypy is understanding whether social deficits arise from receiving less pleasure from social activities or from participating less in high-pleasure activities. However, limited information exists on what constitutes highly pleasurable, common social activities. In this study, 357 college students rated the frequency and enjoyment of 38 social activities. Our aims were to categorize activities based on their frequency and enjoyment, and whether these correlated with validated social functioning and schizotypy measures. We found that social activities could be characterized based on their frequency and enjoyment and created a frequency-enjoyment matrix that could be useful for future studies. Activities were correlated with social functioning, generally reaching a small effect size level, with increasing frequency and enjoyment showing associations with greater social functioning. Further, negative and disorganized-but not positive-traits were associated with less engagement and pleasure. Although follow-up studies in community samples are needed, our findings have the potential to help researchers and clinicians better understand which activities participants are more likely to engage in and derive pleasure from. The findings may also illustrate the extent to which social deficits may be due to less engagement or less pleasure from social activities, as well as which aspects of schizophrenia-spectrum disorders are associated with these facets of social functioning.

Psychosis superspectrum I: Nosology, etiology, and lifespan development

This review describes the Hierarchical Taxonomy of Psychopathology (HiTOP) model of psychosis-related psychopathology, the psychosis superspectrum. The HiTOP psychosis superspectrum was developed to address shortcomings of traditional diagnoses for psychotic disorders and related conditions including low reliability, arbitrary boundaries between psychopathology and normality, high symptom co-occurrence, and heterogeneity within diagnostic categories. The psychosis superspectrum is a transdiagnostic dimensional model comprising two spectra-psychoticism and detachment-which are in turn broken down into fourteen narrow components, and two auxiliary domains-cognition and functional impairment. The structure of the spectra and their components are shown to parallel the genetic structure of psychosis and related traits. Psychoticism and detachment have distinct patterns of association with urbanicity, migrant and ethnic minority status, childhood adversity, and cannabis use. The superspectrum also provides a useful model for describing the emergence and course of psychosis, as components of the superspectrum are relatively stable over time. Changes in psychoticism predict the onset of psychosis-related psychopathology, whereas changes in detachment and cognition define later course. Implications of the superspectrum for genetic, socio-environmental, and longitudinal research are discussed. A companion review focuses on neurobiology, treatment response, and clinical utility of the superspectrum, and future research directions.

Childhood Schizotypy and Adolescent Mental Disorder

BACKGROUND AND HYPOTHESIS

Schizotypy provides a framework for understanding the developmental nature of psychotic disorders and a means of identifying "at-risk" individuals early in the lifespan. However, there is a lack of prospective longitudinal research examining the relationship between schizotypy in childhood and later psychotic and other mental disorders. We hypothesized that distinct profiles of schizotypy in childhood would be differentially associated with psychotic and other mental disorders emerging later in adolescence.

STUDY DESIGN

In a large population cohort of Australian young people (n = 26 837), we prospectively examined the relationship between person-centered profiles of schizotypy identified in middle childhood (age ~11 years) and adolescent diagnoses (age ~13-18 years) across 7 types of mental disorders using multinomial logistic regression.

RESULTS

Membership in any of 3 childhood schizotypy profiles (true schizotypy, affective schizotypy, or introverted schizotypy) was associated with an increased likelihood of being diagnosed with any type of mental disorder in adolescence; effects were strongest for the true schizotypy group (aOR = 3.07, 95% CI = 2.64, 3.57), followed by the introverted (aOR = 1.94, 95% CI = 1.75, 2.15) and affective (aOR = 1.29, 95% CI = 1.13, 1.47) schizotypy groups. Six of the 7 types of mental disorders measured (including psychotic disorders) were associated with at least 1 schizotypy group.

CONCLUSIONS

Schizotypy in middle childhood is an important correlate of mental disorders in adolescence; however, it does not appear to be specifically associated with psychotic disorders in this age group.

I don't understand how I feel: mediating role of impaired self-mentalizing in the relationship between childhood adversity and psychosis spectrum experiences

Introduction

Childhood adversity is associated with the severity of multiple dimensions of psychosis, but the mechanisms underpinning the close link between the two constructs is unclear. Mentalization may underlie this relationship, as impaired mentalizing is found in various stages of the psychosis continuum. Nonetheless, the differential roles of self- and other-mentalizing in psychosis are not well understood.

Methods

Parallel multiple mediation was conducted for the relationship between a diverse range of childhood adversity types, including intentional and nonintentional harm, and schizotypy (positive, negative, disorganized), psychotic-like experiences (PLE) and paranoia via self-mentalizing (attention to emotions and emotional clarity) and other-mentalizing in n = 1,156 nonclinically ascertained young adults.

Results

Significant parallel multiple mediation models were found for all psychotic outcomes except negative schizotypy. The associations between intentionally harmful childhood adversity and psychotic outcomes were significantly mediated by increased attention to emotions for most models and decreased emotional clarity for some models. No significant mediation was found for parental loss. Paternal abuse was only mediated by attention to emotions whereas the effects of maternal abuse were mediated by attention to emotions and emotional clarity. Other-mentalizing only showed mediating effects on one of thirty models tested.

Conclusion

Results highlight the mediating role of impaired self-mentalizing in the association between childhood adversity and psychosis. This is consistent with disturbances of self-concept and self-boundary characterizing, in particular, the positive dimension of psychosis. Maternal versus paternal figures may contribute differentially to the development of mentalizing. These results could inform future preventative interventions, focusing on the development and maintenance of self-mentalizing.

Impaired mnemonic discrimination in children and adolescents at risk for schizophrenia

People with schizophrenia and their high-risk, first-degree relatives report widespread episodic memory impairments that are purportedly due, at least in part, to failures of mnemonic discrimination. Here, we examined the status of mnemonic discrimination in 36 children and adolescents (aged 11-17 years) with and without familial risk for schizophrenia by employing an object-based recognition task called the Mnemonic Similarity Task (MST). The MST assesses the ability to discriminate between studied images and unstudied images that are either perceptually similar to studied images or completely novel. We compared 16 high-risk, unaffected first-degree relatives of people with schizophrenia, bipolar disorder, and/or schizoaffective disorder to 20 low-risk, control participants. High-risk participants showed worse mnemonic discrimination than low-risk participants, with no difference in recognition memory or perceptual discrimination. Our findings demonstrate that mnemonic discrimination deficits previously observed in people with schizophrenia are also present in their young, high-risk, first-degree relatives.

Schizotypal traits in a large sample of high-school and university students from Tunisia: correlates and measurement invariance of the arabic schizotypal personality questionnaire across age and sex

BACKGROUND

The main goal of the present study was to examine the characteristics of schizotypal traits and their correlations with genetic (i.e., family history of mental illness), demographic (i.e., age, sex), environmental (e.g., income, urbanicity, tobacco/alcohol/cannabis use), and psychological (i.e., personal history of mental illness other than psychosis) factors in Tunisian high-school and university students. Our secondary goal was to contribute the literature by examining the factor structure and factorial invariance of the Arabic Schizotypal Personality Questionnaire (SPQ) across sex and age (adolescents [12-18 years] vs. young adults [18-35 years]) groups.

METHOD

This was a cross-sectional study involving 3166 students: 1160 (36.6%) high-school students (53.0% females, aged 14.9 ± 1.8); and 2006 (63.4%) university students (63.9% females, aged 21.8 ± 2.3). All students were asked to complete a paper-and-pencil self-administered questionnaire containing sociodemographic characteristics as well as the Arabic version of the SPQ.

RESULTS

The total sample yielded total SPQ scores of 24.1 ± 16.6 out of 74. The SPQ yielded good composite reliability as attested by McDonald's omega values ranging from .68 to .80 for all nine subscales. Confirmatory Factor Analysis indicated that fit of the 9-factor model of SPQ scores was acceptable. This model is invariant (at the configural, metric and structural levels) across sex and age. Except for "Odd or eccentric behavior", all schizotypy features were significantly higher among female students compared to males. Multivariable analyses showed that female sex, being a university student, lowest family incomes, tobacco use, and having a personal history of psychiatric illness were significantly associated with higher positive, negative and disorganized schizotypy subscales scores.

CONCLUSION

Future research still needs to confirm our findings and investigate the contribution of the identified factors in the development of clinical psychosis. We can also conclude that the Arabic SPQ is appropriate for measuring and comparing schizotypy across age and sex in clinical and research settings. These findings are highly relevant and essential for ensuring the clinical utility and applicability of the SPQ in cross-cultural research.

The effects of base rate neglect on sequential belief updating and real-world beliefs

Base-rate neglect is a pervasive bias in judgment that is conceptualized as underweighting of prior information and can have serious consequences in real-world scenarios. This bias is thought to reflect variability in inferential processes but empirical support for a cohesive theory of base-rate neglect with sufficient explanatory power to account for longer-term and real-world beliefs is lacking. A Bayesian formalization of base-rate neglect in the context of sequential belief updating predicts that belief trajectories should exhibit dynamic patterns of dependence on the order in which evidence is presented and its consistency with prior beliefs. To test this, we developed a novel 'urn-and-beads' task that systematically manipulated the order of colored bead sequences and elicited beliefs via an incentive-compatible procedure. Our results in two independent online studies confirmed the predictions of the sequential base-rate neglect model: people exhibited beliefs that are more influenced by recent evidence and by evidence inconsistent with prior beliefs. We further found support for a noisy-sampling inference model whereby base-rate neglect results from rational discounting of noisy internal representations of prior beliefs. Finally, we found that model-derived indices of base-rate neglect-including noisier prior representation-correlated with propensity for unusual beliefs outside the laboratory. Our work supports the relevance of Bayesian accounts of sequential base-rate neglect to real-world beliefs and hints at strategies to minimize deleterious consequences of this pervasive bias.

The stress-vulnerability model on the path to schizophrenia: Interaction between BDNF methylation and schizotypy on the resting-state brain network

The interplay between schizophrenia liability and environmental influences has been considered to be responsible for the development of schizophrenia. Recent neuroimaging studies have linked aberrant functional connectivity (FC) between the default-mode network (DMN) and the frontoparietal network (FPN) in the resting-state to the underlying neural mechanism of schizophrenia. By using schizotypy as the proxy for genetic-based liability to schizophrenia and methylation of brain-derived neurotrophic factor (BDNF) to represent environmental exposure, this study investigated the impact of the interaction between vulnerability and the environment on the neurobiological substrates of schizophrenia. Participants in this study included 101 healthy adults (HC) and 46 individuals with ultra-high risk for psychosis (UHR). All participants were tested at resting-state by functional magnetic resonance imaging, and group-independent component analysis was used to identify the DMN and the FPN. The Perceptual Aberration Scale (PAS) was used to evaluate the schizotypy level. The methylation status of BDNF was measured by pyrosequencing. For moderation analysis, the final sample consisted of 83 HC and 32 UHR individuals. UHR individuals showed reduced DMN-FPN network FC compared to healthy controls. PAS scores significantly moderated the relationship between the percentage of BDNF methylation and DMN-FPN network FC. The strength of the positive relationship between BDNF methylation and the network FC was reduced when the schizotypy level increased. These findings support the moderating role of schizotypy on the neurobiological mechanism of schizophrenia in conjunction with epigenetic changes.

A network analysis on the relationship between loneliness and schizotypy

BACKGROUND

Schizotypy is a multidimensional personality trait related to the heightened risk for the development of schizophrenia spectrum disorders. While it has been suggested that loneliness may be associated with schizotypy in general, whether it relates to the specific schizotypal traits differentially remains unknown. Besides, as loneliness often co-occurs with depression and anxiety, it is important to delineate its relationship with schizotypy in consideration of these co-occurring emotional disturbances.

METHODS

A demographically diverse sample of young people was obtained from multiple sources. The validated sample consisted of 2089 participants (68.4% female, age range: 18-30). The structural relationship between loneliness and schizotypy was modelled using a network analytic approach. The Gaussian graphical model with loneliness and nine schizotypal traits as nodes was first estimated without, and then with adjustment for the levels of depressive and anxiety symptoms. Edges were estimated as unique associations between nodes.

RESULTS

'Suspiciousness', 'odd beliefs or magical thinking', 'no close friends', 'constricted affect' and 'excessive social anxiety' were linked to loneliness directly. Loneliness was found to be more strongly associated with 'suspiciousness' and 'no close friends' than other schizotypal traits. After adjustment for the levels of depressive and anxiety symptoms, the above direct edges remained robust.

LIMITATIONS

The use of cross-sectional data indicated only undirected associations between variables.

CONCLUSIONS

Loneliness was more strongly linked to some schizotypal traits than others, with the relationships maintaining above and beyond the effects of anxiety and depression. These findings warrant further investigation of the specific relationships between loneliness and individual schizotypal traits.

Activity system, schizotypal personality, and mentalization: A study between halted activity and COVID-19 conducted in Henan, China

The pandemic-related lifestyle has potentially imposed crucial disturbances on daily and long-term activities, which, in turn, were associated with thought disturbance. This study investigates how the characteristics of the activity system during pandemic-related restrictions are associated with other psychomental aspects. By focusing on PTSD, mentalization, and schizotypal personality, and by inquiring about the main components of the activity system of 852 college students (Zhengzhou, Henan, China)- including the goals orienting their activity, goals' terms and types, the motivation levels and sources, the activity type and engagement time, the flow of the activity, and how due to pandemic lifestyle-results revealed that the activity system's components have significant associations with PTSD, reflective function, and schizotypal traits. Additionally, some of the activity system's elements have a significant predictive role regarding schizotypal traits. The study considered that the life narrative during the pandemic has been disturbed; hence, this may have a crucial effect on mind coherence. Additionally, the outcomes from the pandemic context will support mental health interventions in other similar contexts where the life narrative is severely affected.

Schizotypal traits across the amyotrophic lateral sclerosis-frontotemporal dementia spectrum: pathomechanistic insights

BACKGROUND

Psychiatric presentations similar to that observed in primary psychiatric disorders are well described across the amyotrophic lateral sclerosis-frontotemporal dementia (ALS-FTD) spectrum. Despite this, schizotypal personality traits associated with increased risks of clinical psychosis development and poor psychosocial outcomes have never been examined. The current study aimed to provide the first exploration of schizotypal traits and its neural underpinnings in the ALS-FTD spectrum to gain insights into a broader spectrum of psychiatric overlap with psychiatric disorders.

METHODS

Schizotypal traits were assessed using the targeted Schizotypal Personality Questionnaire in 99 participants (35 behavioural variant FTD, 10 ALS-FTD and 37 ALS patients, and 17 age-, sex- and education-matched healthy controls). Voxel-based morphometry analysis of whole-brain grey matter volume was conducted.

RESULTS

Relative to controls, pervasive schizotypal personality traits across positive and negative schizotypy and disorganised thought disorders were identified in behavioural variant FTD, ALS (with the exception of negative schizotypy) and ALS-FTDALS-FTD patients (all p < .013), suggesting the presence of a wide spectrum of subclinical schizotypal symptoms beyond classic psychotic symptoms. Atrophy in frontal, anterior cingulate and insular cortices, and caudate and thalamus was involved in positive schizotypy, while integrity of the cerebellum was associated with disorganised thought disorder traits.

CONCLUSIONS

The frontal-striatal-limbic regions underpinning manifestation of schizotypy in the ALS-FTDALS-FTD spectrum are similar to that established in previous schizophrenia research. This finding expands the concept of a psychiatric overlap in ALS-FTD and schizophrenia, and suggests potentially common underlying mechanisms involving disruptions to frontal-striatal-limbic networks, warranting a transdiagnostic approach for future investigations.

The effect of schizotypy on spatial learning in an environment with a distinctive shape

In two experiments, participants completed the Oxford-Liverpool Inventory of Feelings and Experiences measuring schizotypal traits across four dimensions (unusual experiences, cognitive disorganization, introvertive anhedonia, and impulsive non-conformity). They then took part in a virtual navigation task where they were required to learn about the position of a hidden goal with reference to geometric cues of a rectangular arena or rely on colored wall panels to find the hidden goal in a square-shaped arena. Unusual experience and cognitive disorganization were significant predictors of the use of geometric cues, but no significant predictors were found for the use of wall panels. Implications to hippocampal function and the clinical domain are considered.

Ambiguous handedness and visuospatial pseudoneglect in schizotypy in physical and computer-generated virtual environments

Virtual reality (VR) technology has increased clinical attention in the health care of schizophrenia spectrum disorders in both diagnoses of the symptoms and assessment of schizotypal traits. However, the exact nature of VR-induced positive treatment effect in schizotypy is still unknown. In this study, VR technology was used as a non-invasive neurocognitive trigger to test the asymmetric visuospatial representational instability found in individuals with high schizotypy. The study aimed to reveal the brain functional hemispheric laterality in physical and virtual realities in individuals with schizotypal traits. Fifty-one healthy, right-handed participants (24 males and 27 females) were enrolled through public advertisements. Hemispheric functional asymmetry was measured by the Line Bisection Task (LBT). The results revealed that (a) LBT bias in the physical reality showed a handedness-related leftward pseudoneglect, however, similar handedness-related pseudoneglect in VR has not been found. (b) Comparing LBT bias in physically real and VR environments showed rightward drift in VR environments independently to the degree of handedness. (c) The schizotypy has no association with handedness, however, the cognitive schizotypy is related to the LBT bias. Higher cognitive schizotypy in VR associated with left hemispatial pseudoneglect. In conclusion, schizotypy is associated with ambiguous behavioral and cognitive functional laterality. In individuals with high cognitive schizotypy, the VR environment enhanced the representational articulation of the left hemispace. This effect may be originated from the enhancement of the right hemisphere overactivation and is followed by a lower mental control of the overt behavior.

Episodic memory impairment in children and adolescents at risk for schizophrenia: A role for context processing

People with schizophrenia experience episodic memory impairments that have been theorized to reflect deficits in processing context (e.g., spatio-temporal features tied to a specific event). Although past research has reported episodic memory impairments in young people at-risk for schizophrenia, the extent to which these impairments reflect context processing deficits remains unknown. We addressed this gap in the literature by examining whether children and adolescents at risk for schizophrenia exhibit context processing deficits during free recall, a memory task with high contextual demands. Our sample included three groups (N = 58, 9–16 years old) varying in risk for schizophrenia:16 high-risk, unaffected first-degree relatives of patients with schizophrenia, bipolar disorder, and/or schizoaffective disorder, 22 clinical control participants with a comorbid disorder (ADHD and/or an anxiety disorder), and 20 healthy control participants. Participants first completed a free recall task and then completed a recognition memory task. Based on established theories of episodic memory, we assumed that context processing played a more pivotal role in free recall than recognition memory. Consequently, if schizophrenia risk is associated with context processing deficits, then memory impairment should be present in free recall measures that are most sensitive to context processing (i.e., recall accuracy and temporal contiguity). Consistent with this prediction, free recall accuracy and temporal contiguity were lower for the high-risk group than the healthy controls, whereas recognition memory was comparable across groups. These findings suggest that episodic memory impairments associated with schizophrenia in unaffected, first-degree relatives may reflect context processing deficits.

Suicidal ideation, suicide literacy and stigma, disclosure expectations and attitudes toward help-seeking among university students: The impact of schizotypal personality traits

BACKGROUND

Similarly to patients with schizophrenia, non-clinical individuals with schizotypal traits have been reported to show an increased risk for suicide-related outcomes. We aimed to assess suicidal ideation, and to determine factors that may have associations with help-seeking attitudes in high schizotypal individuals as compared to low schizotypal individuals.

METHOD

We carried out a cross-sectional survey. The Schizotypal Personality Questionnaire, the attitudes toward seeking professional psychological help scale-short form, the disclosure expectations scale, the scale of suicide ideation, the stigma of suicide scale-short form, the literacy of suicide scale, and the depression anxiety stress scales were administered to 504 college students. A total of 51 students were classified in the high-schizotypy group, and 50 were classified in the low-schizotypy group.

RESULTS

High-schizotypal students experienced significantly more suicidal ideation, had greater literacy of suicide, had more glorification of suicide, had higher anticipated risks of disclosure and more negative help-seeking attitudes than low-schizotypal students. After controlling for sociodemographic (age, gender, income and tobacco use) and psychosocial variables (personal psychiatric history, family history of suicide, personal history of suicide attempt[s]), depression and suicide ideation), disclosure expectations had both a significant negative independent effect through anticipated risks, and a positive independent effect through anticipated benefits, on high-schizotypal students' help-seeking attitudes.

CONCLUSION

The apprehension and reluctance to seek help found in high-schizotypal students highlight an urgent need to further understand barriers to help-seeking among at-risk adolescents, and what may motivate them to reach out for support when they are more at-risk for suicide.

Polygenic risk for schizophrenia and schizotypal traits in non-clinical subjects

BACKGROUND

Schizotypy is a putative risk phenotype for psychosis liability, but the overlap of its genetic architecture with schizophrenia is poorly understood.

METHODS

We tested the hypothesis that dimensions of schizotypy (assessed with the SPQ-B) are associated with a polygenic risk score (PRS) for schizophrenia in a sample of 623 psychiatrically healthy, non-clinical subjects from the FOR2107 multi-centre study and a second sample of 1133 blood donors.

RESULTS

We did not find correlations of schizophrenia PRS with either overall SPQ or specific dimension scores, nor with adjusted schizotypy scores derived from the SPQ (addressing inter-scale variance). Also, PRS for affective disorders (bipolar disorder and major depression) were not significantly associated with schizotypy.

CONCLUSIONS

This important negative finding demonstrates that despite the hypothesised continuum of schizotypy and schizophrenia, schizotypy might share less genetic risk with schizophrenia than previously assumed (and possibly less compared to psychotic-like experiences).

High Predictive Accuracy of Negative Schizotypy With Acoustic Measures

Negative schizotypal traits potentially can be digitally phenotyped using objective vocal analysis. Prior attempts have shown mixed success in this regard, potentially because acoustic analysis has relied on small, constrained feature sets. We employed machine learning to (a) optimize and cross-validate predictive models of self-reported negative schizotypy using a large acoustic feature set, (b) evaluate model performance as a function of sex and speaking task, (c) understand potential mechanisms underlying negative schizotypal traits by evaluating the key acoustic features within these models, and (d) examine model performance in its convergence with clinical symptoms and cognitive functioning. Accuracy was good (> 80%) and was improved by considering speaking task and sex. However, the features identified as most predictive of negative schizotypal traits were generally not considered critical to their conceptual definitions. Implications for validating and implementing digital phenotyping to understand and quantify negative schizotypy are discussed.

Sharing positive events: Ecological momentary assessment of emotion regulation via social capitalization in schizotypy

Emotional deficits are prominent in schizophrenia-spectrum psychopathology and linked with poorer outcomes. Schizotypy, an underlying personality organization that putatively confers vulnerability to developing schizophrenia, has been associated with increased negative affect, decreased positive affect, and some difficulty with emotion regulation. This study explored the role of social capitalization, the upregulation of positive emotion when positive life events are shared with others, in schizotypy. Social capitalization is relevant for schizotypy given its association with social functioning and social motivation abnormalities. Using mobile assessment methods, a sample of college students (N=73) completed daily surveys via a mobile application two times per day for seven days and made daily ratings of mood and answered questions regarding any capitalization attempt for a positive event. Results indicated that higher schizotypy and not sharing an event were independently associated with lower happiness and increased sadness and anxiety. When an event was shared, lower schizotypy and supportive/enthusiastic response perception were independently associated with increased happiness. No significant interactions were observed between schizotypy and social capitalization variables. Future research would benefit from exploring the role that other common schizotypy concomitants, e.g., social anxiety or social disconnection, play in social capitalization and the extent this is helped or hindered via mass personal technological mediums.

The association of multidimensional schizotypy with symptoms and impairment across racial groups

The assessment of schizotypy and schizophrenia-spectrum psychopathology has historically been adversely impacted by multiple forms of measurement bias, including racial bias. The Multidimensional Schizotypy Scale (MSS) was developed using modern scale construction methods to minimize measurement bias in the assessment of schizotypic traits. However, studies have not examined the validity of the measurement across different racial groups. The present study examined whether the associations of MSS positive, negative, and disorganized schizotypy subscales with interview-assessed ratings of functioning, schizophrenia-spectrum personality traits, and depressive disorders were generally comparable across nonclinically ascertained samples of Black (n = 46), Asian (n = 87), and White (n = 116) young adults. Consistent with previous findings, all three schizotypy subscales were associated with impairment and schizotypal and paranoid traits. Negative schizotypy was associated with schizoid traits, and disorganized schizotypy was associated with depressive disorders. These associations were comparable across the racial groups, supporting the use of the MSS in these groups. Culturally and empirically valid assessments are essential for providing accurate assessments across racial/ethnic groups and reducing the risk of overpathologizing people of color. The present findings support the cross-cultural validity of the MSS; however, future studies should expand upon these findings by including more diverse samples and longitudinal designs.

Psychosocial Stress, Social Support, and the Escalation of Schizotypal Symptoms

ABSTRACT

Although research suggests that psychosocial stress is associated with an increase in schizotypal symptoms, the type of stressor associated with increased symptomatology is unclear, and no study has examined whether social support might mitigate the effects of stress on symptom change. In this study, 131 young adults completed measures of schizotypal symptoms, major life events, daily hassles, and perceptions of social support at baseline, and measures of stress and symptoms again 4 to 6 weeks later. Results indicated, after controlling for baseline measures, that for those scoring low on schizotypal measures at baseline, only low levels of social support were associated with increased symptoms. For those scoring high on the schizotypal scales at baseline, however, both major life events and daily hassles were associated with increased symptomatology, but only when perceptions of social support at baseline were low. The results suggest that it is important to assess both perceptions of social support and baseline symptomatology when examining whether major life events and daily stress are associated with increased psychotic symptoms. Both types of psychosocial stress are associated with an increase in symptoms, but only for those who are already showing above average symptoms and only when social support is low.

Adaptive and maladaptive features of schizotypy clusters in a community sample

Schizotypal personality traits correlate with psychopathology and impaired functional outcome. Yet advantageous aspects of positive schizotypy may exist which could promote resilience and creativity, and several studies have identified a high positive but low negative schizotypy group with some signs of adaptation. The aim of our study was to clarify whether such individuals demonstrate only traits associated with well-being, or they also have traits that predict impairment. Participants (N = 643 students, 71.5% female) completed measures of schizotypy, resilience, self-esteem, self-concept clarity, and absorption. We identified four clusters: an overall low schizotypy, an overall high schizotypy, a disorganised-interpersonal schizotypy and a positive schizotypy cluster. The overall high schizotypy cluster seemed to be the most vulnerable as it was the least resilient and showed widespread maladaptation, whereas the high positive schizotypy cluster had intact self-esteem and high resilience and its elevated absorption may hold the promise for adaptive outcomes such as creativity and positive spirituality. However, the high positive schizotypy cluster lacked self-concept clarity. The results suggest that individuals showing high positive and low negative schizotypy demonstrate features promoting mental well-being to an extent that is higher than in all the other clusters, while their self-concept impairment is similar to that observed in the high and the disorganised-interpersonal schizotypy clusters. Better understanding of these factors could be informative for prevention and treatment of psychosis-spectrum disorders.

Nonclinical psychotic-like experiences and schizotypy dimensions: Associations with hippocampal subfield and amygdala volumes

Schizotypy and psychotic‐like experiences (PLE) form part of the wider psychosis continuum and may have brain structural correlates in nonclinical cohorts. This study aimed to compare the effects of differential schizotypy dimensions, PLE, and their interaction on hippocampal subfields and amygdala volumes in the absence of clinical psychopathology. In a cohort of 367 psychiatrically healthy individuals, we assessed schizotypal traits using the Oxford‐Liverpool Inventory of Life Experiences (O‐LIFE) and PLE using the short form of the Prodromal Questionnaire (PQ‐16). Based on high‐resolution structural MRI scans, we used automated segmentation to estimate volumes of limbic structures. Sex and total intracranial volume (Step 1), PLE and schizotypy dimensions (Step 2), and their interaction terms (Step 3) were entered as regressors for bilateral amygdala and hippocampal subfield volumes in hierarchical multiple linear regression models. Positive schizotypy, but not PLE, was negatively associated with left amygdala and subiculum volumes. O‐LIFE Impulsive Nonconformity, as well as the two‐way interaction between positive schizotypy and PLE, were associated with larger left subiculum volumes. None of the estimators for right hemispheric hippocampal subfield volumes survived correction for multiple comparisons. Our findings support differential associations of hippocampus subfield volumes with trait dimensions rather than PLE, and support overlap and interactions between psychometric positive schizotypy and PLE. In a healthy cohort without current psychosis risk syndromes, the positive association between PLE and hippocampal subfield volume occurred at a high expression of positive schizotypy. Further studies combining stable, transient, and genetic parameters are required.

Association between traumatic stressful events and schizotypal symptoms among a community-based sample of adolescents: A 2-year longitudinal study

BACKGROUND

Traumatic stressful events (TSEs) are among the most studied risk factors for subsequent schizotypal symptoms. However, specificity and aggregate effects of trauma exposure on schizotypal symptoms remain unclear. This study investigates these relationships among a community-based sample of US adolescents.

MATERIAL AND METHODS

A sub-sample of 426 adolescents (51.6% female) from the Philadelphia Neurodevelopmental Cohort study were selected for longitudinal follow-up based on presence (n = 209) or absence (n = 217) of psychosis spectrum symptoms (PSS). At baseline, they completed assessments of demographic, TSEs, other psychopathology (e.g., PSS, anxiety, depression, and behavioral disorder) and family history of psychopathology. Schizotypal symptom dimensions (cognitive-perceptual, interpersonal and disorganized) were evaluated approximately two years later.

RESULTS

More than half of adolescents experienced at least one type of TSE. Adolescents with assaultive trauma reported about 1.5 times as many symptoms on all three schizotypal symptom dimensions, compared to adolescents with non-assaultive TSE, adjusting for demographic and family history variables. No statistical significance was found after further adjusting for other baseline psychopathology (p > 0.05). There was a significant aggregate effect of TSEs on cognitive-perceptual symptoms with small effect size (p < 0.001, Cohen's f2 = 0.034).

CONCLUSIONS

We found evidence of an association between aggregate TSEs and cognitive-perceptual symptoms, but trauma type was not associated with schizotypal symptom dimensions when controlling for potential confounders. Our findings highlight the importance of considering aggregate TSE effects and potential confounds when examining associations between TSEs and schizotypy. Trauma and psychosis spectrum screening may be important in the effort to provide trauma-informed care.

Schizotypal personality traits and multisensory integration: An investigation using the McGurk effect

Multisensory integration, the process by which sensory information from different sensory modalities are bound together, is hypothesized to contribute to perceptual symptomatology in schizophrenia, in whom multisensory integration differences have been consistently found. Evidence is emerging that these differences extend across the schizophrenia spectrum, including individuals in the general population with higher levels of schizotypal traits. In the current study, we used the McGurk task as a measure of multisensory integration. We measured schizotypal traits using the Schizotypal Personality Questionnaire (SPQ), hypothesizing that higher levels of schizotypal traits, specifically Unusual Perceptual Experiences and Odd Speech subscales, would be associated with decreased multisensory integration of speech. Surprisingly, Unusual Perceptual Experiences were not associated with multisensory integration. However, Odd Speech was associated with multisensory integration, and this association extended more broadly across the Disorganized factor of the SPQ, including Odd or Eccentric Behaviour. Individuals with higher levels of Odd or Eccentric Behaviour scores also demonstrated poorer lip-reading abilities, which partially explained performance in the McGurk task. This suggests that aberrant perceptual processes affecting individuals across the schizophrenia spectrum may relate to disorganized symptomatology.

Associations between schizotypal personality features, mentalizing difficulties and thought problems in a sample of community adolescents

AIM

Schizotypal trait expression and mentalizing impairments represent key factors associated with increased vulnerability for schizophrenia. In the current study, we analysed the nature of associations linking specific schizotypal personality features to mentalizing difficulties during adolescence. Furthermore, we examined the extent to which mentalizing difficulties mediate the relationship between schizotypal trait features and self-reported thought problems.

METHODS

One hundred and five community adolescents (M_age = 15.72; SD = 1.91) completed a recently developed self-report measure of mentalizing (Reflective Functioning Questionnaire [RFQ]), evaluating the degree of certainty (RFQc-scale) and uncertainty (RFQu-scale) with which individuals utilize mental state information to understand their own and others' behaviour. High scores on the RFQu-scale reflect poor usage of mental state information, while high scores on the RFQc-scale capture adaptive levels of certainty about mental states. Self-report questionnaires were also used to assess schizotypal trait expression, thought problems and symptoms of anxiety/depression.

RESULTS

Linear regression models indicated that schizotypal features of social anxiety and odd speech accounted for increased RFQu scores, while odd speech also accounted for reduced RFQc scores. RFQu partially mediated the effects of social anxiety and odd speech on the level of thought problems in the sample.

CONCLUSIONS

Present findings suggest that schizotypal features that impede interpersonal communication during adolescence are linked to difficulties in mental state understanding. Our study also provides original data suggesting that the effects of social anxiety and odd speech on psychosis-risk may partially depend upon the level of mentalizing uncertainty. Mentalizing difficulties may constitute important clinical assessment and early prevention treatment targets in adolescents who demonstrate schizotypal features.

The network structure of schizotypy in the general population

Schizotypal personality traits show similarity with schizophrenia at various levels of analysis. It is generally agreed that schizotypal personality is multidimensional; however, it is still debated whether impulsive nonconformity should be incorporated into theories and measurement of schizotypy. In addition, relatively little is known about the network structure of the four-dimensional model of schizotypal personality. To estimate the network structure of schizotypy, we used data from participants recruited from the community (N = 11,807) who completed the short version of the Oxford-Liverpool Inventory of Feelings and Experiences, a widespread self-report instrument that assesses the positive, negative, disorganised and impulsive domains of schizotypy. We performed community detection, then examined differences between communities in terms of centralities and compared the strength of edges within and between communities. We found communities that almost perfectly corresponded to the a priori-defined subscales (93% overlap, normalised mutual information = 0.74). Items in the disorganisation community had higher closeness centrality relative to items in the other communities (Cliff's Δs ranged from 0.55 to 0.83) and weights of edges within the disorganisation community were stronger as compared to the negative schizotypy and impulsive nonconformity communities (Cliff's Δs = 0.33). Our findings imply that the inclusion of impulsive nonconformity items does not dilute the classical three-factor structure of positive, negative and disorganised schizotypy. The high closeness centrality of disorganisation concurs with theories positing that cognitive slippage and associative loosening are core features of the schizophrenic phenotype.

Resting state alpha oscillatory activity is a valid and reliable marker of schizotypy

Schizophrenia is among the most debilitating neuropsychiatric disorders. However, clear neurophysiological markers that would identify at-risk individuals represent still an unknown. The aim of this study was to investigate possible alterations in the resting alpha oscillatory activity in normal population high on schizotypy trait, a physiological condition known to be severely altered in patients with schizophrenia. Direct comparison of resting-state EEG oscillatory activity between Low and High Schizotypy Group (LSG and HSG) has revealed a clear right hemisphere alteration in alpha activity of the HSG. Specifically, HSG shows a significant slowing down of right hemisphere posterior alpha frequency and an altered distribution of its amplitude, with a tendency towards a reduction in the right hemisphere in comparison to LSG. Furthermore, altered and reduced connectivity in the right fronto-parietal network within the alpha range was found in the HSG. Crucially, a trained pattern classifier based on these indices of alpha activity was able to successfully differentiate HSG from LSG on tested participants further confirming the specific importance of right hemispheric alpha activity and intrahemispheric functional connectivity. By combining alpha activity and connectivity measures with a machine learning predictive model optimized in a nested stratified cross-validation loop, current research offers a promising clinical tool able to identify individuals at-risk of developing psychosis (i.e., high schizotypy individuals).

Swedish Universities Scales of Personality: Relation to Other Personality Instruments

OBJECTIVE

To investigate associations between Swedish universities Scales of Personality (SSP) and scales of the following personality instruments: Structured Clinical Interview for DSM-III-R axis II screening questionnaire (SCID-II screen), revised NEO personality inventory (NEO-PI-R), revised Chapman scales (Chapman) and the psychotic traits questionnaire (STQ).

METHODS

Healthy individuals (n=406) completed self-report personality questionnaires including SSP and at least one more personality inventory. Correlations were calculated between the 13 different SSP subscales as well as SSP's three factors and factors and scales/subscales in SCID-II screen, NEO-PI-R, Chapman and STQ. The main factors of the various instruments were factor analysed. ICC were calculated.

RESULTS

SSP Neuroticism factor correlated with SCID-II cluster C (r=0.71), NEO Neuroticism (r=0.80) and Chapman Social anhedonia (r=0.62). SSP Extraversion factor correlated with NEO Extraversion (r=0.63) and SSP Aggressiveness factor with NEO Agreeableness (r=-0.62). Strong correlations between SSP factors and scales and scales of the other instruments were sparse, although weaker correlations were common.

CONCLUSION

SSP is a useful investigation tool when measuring personality traits related to temperament-like features. SSP partly correlates well to especially three of the NEO-PI-R factors. The different personality inventories are not completely comparable to each other. Instead, they measure personality aspects in partly different ways.

Cognitive-perceptual and disorganized schizotypal traits are nonlinearly related to atypical semantic content on tasks of semantic fluency

Language deficits emerge early in the course of schizophrenia, yet research findings in those at-risk for schizophrenia, such as those with schizotypy, are mixed. The purpose of the present study was to elucidate the relationship of language ability, measured via semantic fluency, to schizotypy, examining both linear and non-linear relations. Semantic fluency data from 295 individuals with varying amounts of schizotypal traits were analyzed utilizing traditional methods (i.e., counting words generated that fit a specific semantic category). The content of semantic fluency responses was also analyzed via a semantic infrequency score (i.e., how infrequent participant responses were relative to all responses generated for the category in the study sample) and a total semantic productivity score (i.e., how many unique words generated overall, including those that did not fit the semantic category). Using traditional methods of scoring, schizotypy was not related to semantic fluency. However, schizotypy was non-linearly related to semantic infrequency and productivity, reflecting atypical semantic activation and processing. In particular, cognitive-perceptual and disorganized, but not interpersonal, traits were related to semantic infrequency and productivity. Valuable content-based information is missed when only analyzing semantic fluency data via the traditional method in the schizophrenia spectrum population. Cognitive-perceptual and disorganized traits, attenuated thought disorder symptoms, evidence the strongest relationship to semantic fluency, further illustrating the link between language and schizophrenia symptoms along the schizophrenia spectrum.

Cognitive Gain or Handicap: Magical Ideation and Self-Absorption in Clinical and Non-clinical Participants

Background: This study aimed to examine magical ideation and absorption traits across non-clinical and clinical groups to determine their potential adaptive and maladaptive functions.

Method: We enrolled 760 healthy participants from neighboring communities (female = 53.2%). Moreover, we recruited 318 patients (female = 66.5%), which included 25, 183, and 110 patients with schizophrenia spectrum disorders, anxiety disorders, and mood disorders, respectively. Potentially adaptive and maladaptive sociocognitive functions were measured to determine the role of magical ideation and self-absorption in patients with psychiatric disorders.

Results: The degree of magical ideation and absorption gradually increased in the following order: anxiety disorders, mood disorders, and schizophrenia spectrum disorders. Furthermore, enhanced self-absorption-related enhanced consciousness traits were essential indicators of the presence of self-integration weakness in patients with schizophrenia spectrum disorders.

Conclusion: Magical ideation and psychological absorption may be considered as mental model construction functions, which result in both gains and handicaps in social adaptation.

Positive schizotypy and the experience of creativity: The distinctive roles of suspiciousness and dispositional mindfulness

Positive schizotypy has been shown to predict emergence of schizophrenia-spectrum disorders, with suspiciousness/paranoia regarded a key risk factor. However, magical thinking and unusual perceptual experiences, other aspects of positive schizotypy, are associated with creativity. We investigated whether suspiciousness attenuates the relationship of magical thinking and unusual experiences with creative experience, and explored the interaction of dispositional mindfulness with positive schizotypy and creative experience. 342 (256 females) healthy adults (mean age: 25.9; SD 8.4) completed online self-report measures of schizotypy, creative experience, and dispositional mindfulness. Moderation analysis showed that suspiciousness attenuated the positive relationship of magical thinking (b = -0.29, p = .03) and unusual perceptual experiences (b = -0.23, p = .01) with an aspect of creative experience related to positive affect - power/pleasure. This effect was not present for 4 other aspects of creative experience. Multiple linear regressions revealed higher dispositional mindfulness to interact with aspects of positive schizotypy associated with heightened creative experience of power/pleasure (b = 0.06, p = .03), clarity/preparation (b = 0.03, p = .004), and differing levels of anxiety associated with creative engagement (b = -0.06, p = .003; b = 0.03, p = .047). Higher dispositional mindfulness was also associated with lower suspiciousness (r_s = -0.33, p < .001). The study highlights the importance of considering the role of suspiciousness/paranoia when investigating the relationship between positive schizotypy and creativity. The findings provide support for the application of mindfulness-based interventions for mitigating psychosis-risk associated with suspiciousness, whilst supporting the otherwise favourable association of positive schizotypy with creativity.

Body-environment integration: Temporal processing of tactile and auditory inputs along the schizophrenia continuum

According to the dimensional approach to psychosis, there is a continuum from low schizotypy to schizophrenia patients. The temporal aspect of sensory processing seems to be compromised across such continuum, as suggested by different studies separately investigating unisensory or multisensory domains. Most of these studies have so far focused primarily on the temporal processing of visual and auditory stimuli, either in schizotypy or schizophrenia, while leaving the tactile domain and the integration of touch with other senses mostly unexplored. Given the relevance of body-related perceptual abnormalities for psychosis proneness, we aimed at filling this gap in the literature across two studies. We asked participants with increasing levels of schizotypy (study 1) and schizophrenia patients (study 2) to perform three simultaneity judgement tasks: a unimodal tactile task, a unimodal auditory task and a bimodal audio-tactile task. Each task allowed estimating a simultaneity range (SR), as a proxy of the individual tolerance to asynchronies in the tactile, auditory and audio-tactile domains, respectively. Results showed larger SRs as the level of schizotypy increases. Specifically, the linear effect of schizotypy levels on the audio-tactile task was stronger than on the auditory task, which in turn was greater than the effect on the tactile task (study 1). Differently, schizophrenia patients showed larger SRs than controls in all the three tasks (study 2). The current study is the first empirical investigation across the continuum from low schizotypy to schizophrenia of the tolerance to asynchronies in the processing of external (auditory) and body-related (tactile) inputs.

High schizotypy traits are associated with reduced hippocampal resting state functional connectivity

Altered hippocampal functioning is proposed to play a critical role in the development of schizophrenia-spectrum disorders. Previous resting state functional Magnetic Resonance Imaging (rs-fMRI) studies report disrupted hippocampal connectivity in patients with psychosis and in individuals with clinical high risk, yet hippocampal connectivity has not been investigated in people with high schizotypy traits. Here we used rs-fMRI to examine hippocampal connectivity in healthy people with low (LS, n = 23) and high levels (HS, n = 22) of schizotypal traits assessed using the Schizotypy Personality Questionnaire. Using a bilateral hippocampal seed region, we examined resting state functional connectivity (RSFC) between hippocampus and striatal, thalamic and prefrontal cortex regions of interest. Compared to LS, HS participants showed lower RSFC between hippocampus and striatum and between hippocampus and thalamus. Whilst the group effect of reduced hippocampal RSFC in striatal and thalamic regions was driven by total schizotypy scores, positive schizotypy subfactor scores were significantly positively correlated with hippocampus-caudate/thalamus RSFC. Group differences in RSFC were not observed between hippocampus and prefrontal cortex. These results demonstrate that subclinical schizotypal traits are associated with altered hippocampal connectivity in striatal and thalamic regions and provide further support that hippocampal dysconnectivity confers risk for schizophrenia spectrum disorders.

Integration of the ICD-11 and DSM-5 Dimensional Systems for Personality Disorders Into a Unified Taxonomy With Non-overlapping Traits

The promise of replacing the diagnostic categories of personality disorder with a better-grounded system has been only partially met. We still need to understand whether our main dimensional taxonomies, those of the International Classification of Diseases, 11th Revision (ICD-11) and the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), are the same or different, and elucidate whether a unified structure is possible. We also need truly independent pathological domains, as they have shown unacceptable overlap so far. To inquire into these points, the Personality Inventory for DSM-5 (PID-5) and the Personality Inventory for ICD-11 (PiCD) were administered to 677 outpatients. Disattenuated correlation coefficients between 0.84 and 0.93 revealed that both systems share four analogous traits: negative affectivity, detachment, dissociality/antagonism, and disinhibition. These traits proved scalar equivalence too, such that scores in the two questionnaires are roughly interchangeable. These four domains plus psychoticism formed a theoretically consistent and well-fitted five-factor structure, but they overlapped considerably, thereby reducing discriminant validity. Only after the extraction of a general personality disorder factor (g-PD) through bifactor analysis, we could attain a comprehensive model bearing mutually independent traits.

Schizotypal traits are not related to multisensory integration or audiovisual speech perception

Multisensory integration, the binding of sensory information from different sensory modalities, may contribute to perceptual symptomatology in schizophrenia, including hallucinations and aberrant speech perception. Differences in multisensory integration and temporal processing, an important component of multisensory integration, are consistently found in schizophrenia. Evidence is emerging that these differences extend across the schizophrenia spectrum, including individuals in the general population with higher schizotypal traits. In the current study, we investigated the relationship between schizotypal traits and perceptual functioning, using audiovisual speech-in-noise, McGurk, and ternary synchrony judgment tasks. We measured schizotypal traits using the Schizotypal Personality Questionnaire (SPQ), hypothesizing that higher scores on Unusual Perceptual Experiences and Odd Speech subscales would be associated with decreased multisensory integration, increased susceptibility to distracting auditory speech, and less precise temporal processing. Surprisingly, these measures were not associated with the predicted subscales, suggesting that these perceptual differences may not be present across the schizophrenia spectrum.

The association of striatal volume and positive schizotypy in healthy subjects: intelligence as a moderating factor

BACKGROUND

Schizotypy, a putative schizophrenia endophenotype, has been associated with brain-structural variations partly overlapping with those in psychotic disorders. Variations in precuneus structure have been repeatedly reported, whereas the involvement of fronto-striatal networks - as in schizophrenia - is less clear. While shared genetic architecture is thought to increase vulnerability to environmental insults, beneficial factors like general intelligence might buffer their effect.

METHODS

To further investigate the role of fronto-striatal networks in schizotypy, we examined the relationship of voxel- and surface-based brain morphometry and a measure of schizotypal traits (Schizotypal Personality Questionnaire, with subscores Cognitive-Perceptual, Interpersonal, Disorganised) in 115 healthy participants [54 female, mean age (s.d.) = 27.57(8.02)]. We tested intelligence (MWT-B) as a potential moderator.

RESULTS

We found a positive association of SPQ Cognitive-Perceptual with putamen volume (p = 0.040, FWE peak level-corrected), moderated by intelligence: with increasing IQ, the correlation of SPQ Cognitive-Perceptual and striatal volume decreased (p = 0.022). SPQ Disorganised was positively correlated with precentral volume (p = 0.013, FWE peak level-corrected). In an exploratory analysis (p < 0.001, uncorrected), SPQ total score was positively associated with gyrification in the precuneus and postcentral gyrus, and SPQ Disorganised was negatively associated with gyrification in the inferior frontal gyrus.

CONCLUSIONS

Our findings support the role of fronto-striatal networks for schizotypal features in healthy individuals, and suggest that these are influenced by buffering factors like intelligence. We conclude that protective factors, like general cognitive capacity, might attenuate the psychosis risk associated with schizotypy. These results endorse the idea of a continuous nature of schizotypy, mirroring similar findings in schizophrenia.

Role for Positive Schizotypy and Hallucination Proneness in Semantic Processing

Semantic processing underpins the organization of verbal information for both storage and retrieval. Deficits in semantic processing are associated with both the risk for and symptoms presented in schizophrenia. However, studies are mixed and could reflect the confounding effects of medication and symptom heterogeneity. Therefore, we considered whether two risk phenotypes, positive schizotypy and hallucinatory predisposition, present in the general population were associated with differential responding profiles for a semantic processing task. One hundred and eighty-three participants completed the Schizotypal Personality Questionnaire, Launay-Slade Hallucination Scale, National Adult Reading Test, a handedness measure, and a computerized semantic relatedness judgment task. Pairs of words were related through their dominant or subordinate meanings, or unrelated. Participants were divided into four groups using a mean split on cognitive-perceptual (positive) schizotypy and hallucination proneness. Significant differences between groups were found for reaction time on the semantic relatedness task, with the high cognitive-perceptual schizotypy groups responding significantly slower to all word pairs compared to their low scoring counterparts. There was some evidence that high hallucination proneness was associated with significantly faster reaction times which may reflect disinhibitive processes, however additional support is required. The results suggest that these two components of psychosis risk are associated with different patterns of responding to semantic processing. More diffuse activation of semantic information appeared to be associated with positive schizotypy, while those predisposed to hallucinations appeared to respond quicker. These results have significant implications in the re-conceptualization of hallucination proneness as distinct from positive schizotypy. Additional research is required to investigate the association between psychotic-like experiences separate from personality variables such as positive schizotypy and semantic processing.

Don't worry, be happy: Protective factors to buffer against distress associated with psychotic experiences

BACKGROUND

Around 6-7% of the general population report psychotic experiences (PEs). Positive PEs (e.g. hearing voices) may increase the risk of development of psychotic disorder. An important predictor of the transition to a psychotic disorder is secondary distress associated with PEs. We examined the moderating effect of potential protective factors on this secondary distress.

METHODS

Data come from 2870 individuals of the HowNutsAreTheDutch study. PEs were assessed with the Community Assessment of Psychic Experience (CAPE) questionnaire and were divided into three subdomains ("Bizarre experiences", "Delusional ideations", and "Perceptual anomalies"). Protective factors explored were having a partner, having a pet, benevolent types of humor, optimism and the high levels of personality traits emotional stability (reversed neuroticism), extraversion, openness to experience, conscientiousness, and agreeableness. We examined whether these protective factors moderated (lowered) the association between frequency of PEs and PE-associated distress.

RESULTS

Due to low prevalence of perceptual anomalies in the sample, this domain was excluded from analysis. No moderating effects were observed of protective factors on the association between bizarre experiences and distress. Having a partner and high levels of optimism, self-enhancing humor, openness, extraversion and emotional stability moderated the association between delusional ideations and secondary distress, leading to lower levels of distress.

CONCLUSIONS

Several protective factors were found to moderate the association between frequency and secondary distress of delusional ideations, with high levels of the protective factors being associated with lower levels of distress. A focus on protective factors could be relevant for interventions and prevention strategies regarding psychotic phenomena.

Social anhedonia and clinical outcomes in early adulthood: A three-year follow-up study within a community sample

Social anhedonia has been employed in psychometric high risk studies to identify putative schizotypes. The current study reports three-year longitudinal results from a community study of social anhedonia: the Maryland Longitudinal Study of Schizotypy (MLSS). The initial recruitment for the MLSS involved mailed questionnaire screening of 2434 18-year olds. Baseline and three-year follow-up laboratory assessments were subsequently conducted with individuals identified as being high in social anhedonia (N = 79) and a comparison sample (N = 79). Across the assessments both groups showed maturational improvement on all clinical symptom measures with declining symptom severity at the follow-up compared to baseline and there were no group differences in personality disorder diagnoses at follow-up. However, compared to the control group, over the three-year follow-up individuals in the social anhedonia group were found to have elevated schizophrenia-spectrum personality disorder (Cluster A) characteristics, greater negative symptom characteristics, and lower global functioning. The social anhedonia group also had lower educational attainment, higher unemployment, and higher rates of mental health service utilization than did the control group. Within the social anhedonia group, social support and family relationships were cross-sectionally related to symptom severity at follow-up, although social support and family variables from baseline were not predictive of clinical symptom outcomes at follow-up. Results indicate that social anhedonia is associated with persistent schizophrenia-spectrum symptoms and functional impairment in early adulthood.

Semantic Search in Psychosis: Modeling Local Exploitation and Global Exploration

Impairments in category verbal fluency task (VFT) performance have been widely documented in psychosis. These deficits may be due to disturbed “cognitive foraging” in semantic space, in terms of altered salience of cues that influence individuals to search locally within a subcategory of semantically related responses (“clustering”) or globally between subcategories (“switching”). To test this, we conducted a study in which individuals with schizophrenia (n = 21), schizotypal personality traits (n = 25), and healthy controls (n = 40) performed VFT with “animals” as the category. Distributional semantic model Word2Vec computed cosine-based similarities between words according to their statistical usage in a large text corpus. We then applied a validated foraging-based search model to these similarity values to obtain salience indices of frequency-based global search cues and similarity-based local cues. Analyses examined whether diagnosis predicted VFT performance, search strategies, cue salience, and the time taken to switch between vs search within clusters. Compared to control and schizotypal groups, individuals with schizophrenia produced fewer words, switched less, and exhibited higher global cue salience, indicating a selection of more common words when switching to new clusters. Global cue salience negatively associated with vocabulary ability in controls and processing speed in schizophrenia. Lastly, individuals with schizophrenia took a similar amount of time to switch to new clusters compared to control and schizotypal groups but took longer to transition between words within clusters. Findings of altered local exploitation and global exploration through semantic memory provide preliminary evidence of aberrant cognitive foraging in schizophrenia.