Three-factor model of schizotypal personality: invariance across culture, gender, religious affiliation, family adversity, and psychopathology

Abnormalities in emotion regulation are associated with negative, but not positive or disorganized schizotypy: An experience sampling study

BACKGROUND

Schizotypy, a multidimensional construct with positive, negative, and disorganized dimensions, represents a vulnerability marker for the development of schizophrenia. Although there has been increasing evidence linking schizotypy to emotion regulation (ER) deficits, the specific association between different schizotypal dimensions and alterations in ER strategy use in daily life remains poorly understood.

METHODS

Using the experience sampling method (ESM), the present study examined the associations between positive, negative, and disorganized schizotypy and ER strategy use in daily life in a nonclinical young adult sample (N = 258). Participants were instructed to report their ER strategy use 5 times a day for 14 days. Four adaptive ER strategies (reflection, reappraisal, social sharing, and distraction) and two maladaptive ER strategies (suppression and rumination) were included.

RESULTS

Multilevel modeling analyses showed that positive schizotypal traits predicted greater use of adaptive ER strategies, while negative schizotypal traits predicted less use of adaptive ER strategies and more frequent use of emotional suppression in daily life. No associations between disorganized schizotypal traits and any ER strategy use were found.

CONCLUSION

Schizotypy dimensions are differentiated by preferences for different ER strategies in daily life. The findings suggest a strong association between negative schizotypy and notable dysfunctions in ER, emphasizing the significance of negative schizotypy as a vulnerability factor for psychosis.

Factor structure and measurement invariance of Schizotypal Personality Questionnaire-Brief Revised (Updated) in India

AIM

Schizotypal Personality Questionnaire-Brief Revised-Updated (SPQ-BRU) is an easy-to-conduct, theoretically consistent, and psychometrically better measure of schizotypal personality. However, its study is limited to developed countries. Thus, in the present study, we tested the factor structure and measurement invariance of SPQ-BRU in India.

METHODS

A sample of 734 college students was selected from two sites (n = 614 from Muzaffarnagar in western Uttar Pradesh and n = 120 from Guhana in Haryana). Confirmatory factor analysis was used to test the good fitness of the different models of SPQ-BRU and the measurement invariance across sex and region.

RESULTS

The first-order nine-factor model was a better-fit model (among a set of first-order and second-order models), whereas the second-order three-factor model was a more parsimonious good-fit model of SPQ-BRU. The nine-factor model was strongly invariant across sex and region. Women had higher social anxiety, ideas of reference, and lower constricted affect than men. Moreover, the Gohana sample was higher on several schizotypal personality facades than the Muzaffarnagar sample.

CONCLUSIONS

The present study supported the cross-cultural validity of schizotypal personality and partially established a reliable and valid SPQ-BRU-Hindi language version.

Schizotypy and perceptual span in a non-clinical sample: a virtual reality study

INTRODUCTION

Individuals with high schizotypy or schizophrenia exhibit difficulties in distributing their attention across space, leading to a reduction in their "perceptual span" - the extent of visual space that can be attended to at once. In this study, we aim to explore the correlation between schizotypy and perceptual span in a non-clinical sample to investigate whether perceptual span correlates with schizotypy across its range.

METHODS

Schizotypy was assessed in fifty-five participants using the Schizotypy Personality Questionnaire (SPQ; Raine, 1991). Participants were required to attend to two dynamic targets displayed in a head-mounted virtual reality display. Perceptual span was estimated as the lateral angle of separation between the two targets beyond which performance in the task dropped to threshold.

RESULTS

Participants with higher schizotypy scores performed significantly worse on the task. Of all the factors associated with schizotypy, the shared variance between Disorganisation and Cognitive/Perceptual Factors was most predictive of task performance.

CONCLUSION

The results support the hypothesis that schizotypy predicts perceptual span in non-clinical samples. Furthermore, the demonstration of a reduced perceptual span in individuals with higher trait schizotypy shows that variations in an individual's capacity to divide attention across space can be accurately captured using a virtual reality head-mounted display.

Threatening Beliefs About Self and Others Moderate the Association Between Psychoticism and Psychological Distress

ABSTRACT

Psychoticism is a multidimensional personality construct involving odd or eccentric behavior, quasi-psychotic experiences, mistrust, interpersonal detachment, and liability for schizophrenia-spectrum disorders, as well as significant distress. Recent advances suggest it can be understood as a dimension that is continuously distributed in the population, leading to questions about factors that contribute to distress and dysfunction among people with a schizotypal liability. We investigated in a large nonclinical sample of young adults whether associations between psychoticism and psychological distress would increase in the presence of threatening beliefs. In our study ( N = 2127), we found that the association between psychoticism and psychological distress is moderated by threatening beliefs including self-criticism, fear of compassion, and socially prescribed perfectionism. These results suggest that distress increases among people with schizotypal traits in the context of negative beliefs about self and others. We discuss implications for clinical practice and directions for further research.

Examining Schizotypal Personality Scales Within and Across Interpersonal Circumplex Surfaces

Differing perspectives on the operationalization of schizotypal personality pathology (STPP) have led to numerous multidimensional assessment measures. The current study applied the interpersonal construct validation approach to self-report data from 856 undergraduate students to formally examine the interpersonal content, similarities, and differences in the subscales of four measures of STPP within and across two interpersonal circumplex surfaces using a bootstrapping methodology for computing confidence intervals around circumplex structural summary method parameters. Results suggested that negative-like expressions of STPP are prototypically and distinctively interpersonal constructs associated with cold and socially avoidant interpersonal problems and hypersensitivity to others' warmth and affection. Positive-like expressions of STPP as assessed by two out of four measures were prototypically and distinctively interpersonal constructs associated with vindictiveness. Across four measures, there was notable overlap in interpersonal correlates among related subscales, suggesting convergent validity. However, subscales containing social anxiety content were associated with more submissive (i.e., socially avoidant) interpersonal problems than subscales without social anxiety content.

Finding normal-to-better neurocognitive indexes in individuals with schizotypal traits using a social role task

Schizophrenia patients make more errors and have longer reaction times (RTs) than healthy controls in most cognitive tasks. Deficits are also observed in subclinical participants having high scores on the schizotypal personality questionnaire (SPQ). They are accompanied by smaller amplitudes of the event-related brain potentials (ERPs) that index attention and semantic- and working-memory. These functions are thus thought to be impaired in individuals having various schizophrenia attributes (SzAs). Nevertheless, normal RTs were recently found in SzAs during a particular self-referential task where half of the stimuli were names of extraordinary social roles (e.g., genius). Each name (ordinary or extraordinary) was presented individually, and participants were asked to decide whether or not they would consider themselves performing the role at any moment of their lives. To further test an absence of cognitive deficits in this task, the ERPs elicited by names of social roles were also examined in 175 healthy participants. The absence of longer RTs in high- than in low-SPQs was replicated. Moreover, the ERPs of high SPQs had larger occipital N1s, larger P2s and larger occipital N400s than those of low SPQs while late positive potentials (LPPs) were of similar amplitudes. Such results are consistent with clinical observations of greater attention and faster processing of stimuli related to extraordinary/delusional beliefs. Further studies should test whether the cognitive deficits found in SzAs are due to the use of tasks and stimuli that are less within their focus of interest than within that of healthy controls.

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.

Mental rotation and schizotypal personality traits: A Bayesian approach

People diagnosed with schizophrenia exhibit mental rotation differences, suggesting that clinical levels of positive symptoms, such as psychotic hallucinations, are related to disruptions in their monitoring and manipulation of mental representations. According to the psychosis continuum, findings in people with a high level of schizotypal personality traits are expected to be qualitatively similar, but research concerning this topic is scarce. A spared mental imagery manipulation in this population only could suggest that this ability might be a possible protective factor, or that the emergence of clinical-level positive symptoms could be paired with disruptions in this capacity. To explore this issue, 205 undergraduate students (122 women) completed a novel mental rotation task identifying the stimulus that was a 90, 180, or 270° rotation of a black circle with colored portions and were assessed with the Schizotypal Personality Questionnaire. Men performed better in most conditions. No relationship was detected between schizotypal personality traits and accuracy in the task. These results do not support that mental imagery manipulation disruptions may be related to schizotypal personality traits in non-clinical populations. Thus, they might instead be associated with the onset of psychosis disorders as mental representation handling is hindered. However, additional research is required including the general population, as well as those with higher levels of psychotic symptoms and psychosis disorders. Future research could also focus on working memory processes related to mental representation manipulations of different sensory modalities such as auditory mental representations and their relationship with schizotypal personality traits and clinical populations.

Race and self-reported paranoia: Increased item endorsement on subscales of the SPQ

There is a dearth of research examining how individual-level and systemic racism may lead to elevated diagnostic and symptom rates of paranoia in Black Americans. The present study employed item response theory methods to investigate item- and subscale-level functioning in the Schizotypal Personality Questionnaire (SPQ) in 388 Black and 450 White participants across the schizophrenia-spectrum (i.e., non-psychiatric controls, individuals with schizophrenia, schizoaffective disorder, or schizotypal personality disorder). It was predicted that (1) Black participants would score significantly higher than Whites on the Suspiciousness and Paranoid Ideation subscale of the SPQ, while controlling for total SPQ severity and relevant demographics and (2) Black participants would endorse these subscale items at a lower latent severity level (i.e., total SPQ score) compared to Whites. Generalized linear modeling showed that Black participants endorsed higher scores on subscales sampling paranoia (e.g., Suspiciousness and Paranoid Ideation), while White participants endorsed higher rates within disorganized/positive symptomatology subscales (e.g., Odd or Eccentric Behavior). IRT analyses showed that Black individuals also endorse items within the Suspiciousness and Paranoid Ideation subscale at lower latent severity levels, leading to inflated subscale scores when compared to their White counterparts. Results indicate prominent race effects on self-reported paranoia as assessed by the SPQ. This study provides foundational data to parse what could be normative endorsements of paranoia versus indicators of clinical risk in Black Americans. Implications and recommendations for paranoia research and assessment are discussed.

Polygenic risk for schizophrenia as a moderator of associations between childhood trauma and schizotypy

Recent evidence shows that genetic and environmental risk factors for psychotic disorders are associated with higher levels of schizotypy (or psychosis proneness) in the general population. However, little is known about how these risk factors interact. We specifically examined whether genetic loading for schizophrenia moderates the association between childhood trauma severity and schizotypy. Schizotypy was measured using the Schizotypal Personality Questionnaire (SPQ), and childhood trauma severity was measured with the Childhood Trauma Questionnaire (CTQ) among a total of 168 participants (comprising 51 healthy individuals, 56 diagnosed with schizophrenia, and 61 with bipolar disorder). Polygenic risk scores (PRS) for schizophrenia were calculated for all participants and examined as a potential moderator of associations between total scores on the CTQ and schizotypy total scores and dimensions (i.e., cognitive-perceptual, interpersonal, disorganised). Multiple linear regression models revealed associations between childhood trauma and all dimensions of schizotypy, but no associations between PRS and schizotypy. A significant interaction between PRS and childhood trauma was evident for the interpersonal and disorganised dimensions of schizotypy, as well as the total score, reflecting positive associations between childhood trauma severity and these two schizotypal dimensions, only for individuals with low or average PRS for schizophrenia. This suggests that trauma may be able to increase risk for psychosis independently of any genetic vulnerability. The present findings are consistent with the idea of several risk pathways for the development of psychotic disorders.

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.

Autistic-Like Traits and Positive Schizotypy as Diametric Specializations of the Predictive Mind

According to the predictive-processing framework, only prediction errors (rather than all sensory inputs) are processed by an organism's perceptual system. Prediction errors can be weighted such that errors from more reliable sources will be more influential in updating prior beliefs. It has previously been argued that autism-spectrum conditions can be understood as resulting from a predictive-processing mechanism in which an inflexibly high weight is given to sensory-prediction errors that results in overfitting their predictive models to the world. Deficits in executive functioning, theory of mind, and central coherence are all argued to flow naturally from this core underlying mechanism. The diametric model of autism and psychosis suggests a simple extension of this hypothesis. If people on the autism spectrum give an inflexibly high weight to sensory input, could it be that people with a predisposition to psychosis (i.e., people high in positive schizotypy) give an inflexibly low weight to sensory input? In this article I argue that evidence strongly supports this hypothesis. An inflexibly low weight given to sensory input can explain such disparate features of positive schizotypy as increased exploratory behavior, apophenia, hyper theory of mind, hyperactive imagination, attentional differences, and having idiosyncratic worldviews.

The positive dimension of schizotypy is associated with a reduced attenuation and precision of self-generated touch

The brain predicts the sensory consequences of our movements and uses these predictions to attenuate the perception of self-generated sensations. Accordingly, self-generated touch feels weaker than an externally generated touch of identical intensity. In schizophrenia, this somatosensory attenuation is substantially reduced, suggesting that patients with positive symptoms fail to accurately predict and process self-generated touch. If an impaired prediction underlies the positive symptoms of schizophrenia, then a similar impairment should exist in healthy nonclinical individuals with high positive schizotypal traits. One hundred healthy participants (53 female), assessed for schizotypal traits, underwent a well-established psychophysics force discrimination task to quantify how they perceived self-generated and externally generated touch. The perceived intensity of tactile stimuli delivered to their left index finger (magnitude) and the ability to discriminate the stimuli (precision) was measured. We observed that higher positive schizotypal traits were associated with reduced somatosensory attenuation and poorer somatosensory precision of self-generated touch, both when treating schizotypy as a continuous or categorical variable. These effects were specific to positive schizotypy and were not observed for the negative or disorganized dimensions of schizotypy. The results suggest that positive schizotypal traits are associated with a reduced ability to predict and process self-generated touch. Given that the positive dimension of schizotypy represents the analogue of positive psychotic symptoms of schizophrenia, deficits in processing self-generated tactile information could indicate increased liability to schizophrenia.

A Developmental Study of Mirror-Gazing-Induced Anomalous Self-Experiences and Self-Reported Schizotypy from 7 to 28 Years of Age

INTRODUCTION

The mirror-gazing task (MGT) is an experimental paradigm inducing anomalous perceptions and anomalous experiences of self-face (ASEs) in the general population, ranging from changes in light and color, to face deformation, to experiencing one's specular image as another identity. Subclinical ASEs have been related to the emergence of the risk for developing psychotic disorders, and inducing such states in the general population could shed light on the factors underlying interindividual differences in proneness to these phenomena. We aimed to examine the influence of schizotypal personality traits on proneness to experiencing induced ASEs from a developmental perspective, from childhood to adulthood.

METHODS

Two hundred and sixteen children, adolescents, and young adults participated in the MGT, and their schizotypal personality traits were assessed with the Schizotypal Personality Questionnaire. Statistical analyses assessed the relationship between schizotypy dimensions and induced ASEs, and we further tested their dynamic relationship as function of age (from childhood to adulthood).

RESULTS

Results confirmed the developmental trajectory of the different schizotypy dimensions, with scores peaking during adolescence, and proneness to induced ASEs seemed to follow a similar developmental trajectory. Moreover, positive (p = 0.001) and disorganized (p = 0.004) dimensions were found to contribute to the proneness to experiencing induced ASEs. Finally, the developmental model showed that positive schizotypy (p = 0.035) uniquely distinguished between experiencing other-identity phenomena between childhood and adulthood.

CONCLUSION

This study has the potential to inform research on early detection of psychosis through a developmental approach and links the concept of schizotypy with processes of perceptual self-distortions.

Schizotypal personality traits and the social learning of fear

Schizotypy can be defined as a combination of traits qualitatively similar to those found in schizophrenia, but milder in their expression, that can be found in clinical and non-clinical populations. In this research, we explore, to our knowledge, for the first time, whether schizotypal personality traits may affect the acquisition of conditioned fear by social means only. Apart from being an essential capacity to ensure learning in safe environments, social fear learning shares important characteristics with direct fear acquisition, which also makes it a great candidate for developing successful extinction procedures. Undergraduate students (n = 72) performed a task of social fear learning. In this task, participants watched a video of a person that simulated to receive electric shocks (unconditioned stimulus; US) paired with a coloured square (conditioned stimulus plus; CS+), while another coloured square was never paired (conditioned stimulus minus; CS−) with the shock. After that, they were presented with a similar sequence of coloured screens. Their Skin Conductance Responses (SCRs) were registered during the whole process. Once they finished, they completed the Schizotypal Personality Questionnaire (SPQ). Our results revealed that participants with a low score in the Cognitive-Perceptual factor of the SPQ exhibited higher SCRs when they saw the US than when they saw the CS− (all ps < 0.01) during the learning phase. Nevertheless, those with higher scores did not present any difference in their SCRs toward both stimuli (all ps > 0.05), a pattern that has been similarly found in schizophrenia. During the final trials of the test phase, participants with the highest scores in the Disorganized factor were the only ones that maintained a higher SCR towards the CS+ than towards the CS− (p = 0.006), which could be associated with an impairment in their extinction processes.

Cumulative sociodemographic disadvantage partially mediates associations between childhood trauma and schizotypy

OBJECTIVES

Risk for psychosis in the general population is characterized by a set of multidimensional traits that are referred to as schizotypy. Higher levels of schizotypy are associated with socioeconomic disadvantage and childhood trauma, just as these risk factors are associated with schizophrenia and bipolar disorder. Here, we set out to investigate whether cumulative sociodemographic disadvantage mediates associations between childhood trauma and schizotypy in adulthood.

METHODS

A sociodemographic cumulative risk (SDCR) score was derived from six risk indices spanning employment, education, income, socioeconomic status, marital, and living circumstances for 197 participants that included both healthy (n = 57) and clinical samples with schizophrenia or schizoaffective disorder (n = 65) or bipolar disorder (n = 75). A series of multiple linear regressions was used to examine the direct and indirect associations among childhood trauma (measured with the Childhood Trauma Questionnaire), the SDCR index, and levels of schizotypy (measured with the Schizotypal Personality Questionnaire).

RESULTS

Schizotypy was independently associated with trauma and the SDCR index. In addition, the SDCR index partially mediated associations between trauma and schizotypy.

CONCLUSIONS

These findings in a mixed sample of healthy and clinical participants represent the full spectrum of schizotypy across health and illness and suggest that effects of childhood trauma on schizotypal personality organization may operate via cumulative socioeconomic disadvantage in adulthood.

PRACTITIONER POINTS

The strong associations between trauma and schizotypy suggest that systematic health screening of children exposed to early life trauma may assist to identify those at risk of developing psychosis. Clinicians should pay attention to various indicators of sociodemographic disadvantage in patients prone to psychosis, in addition to any exposure to trauma during childhood.

The impact of lifetime interpersonal and intentional trauma on cognition and vulnerability to psychosis in bipolar disorder

Background

Studies have shown that over half of individuals with bipolar disorder experience early-life trauma, which may influence clinical outcomes, including suicidality and presence of psychotic features. However, studies report inconsistent findings regarding the effect of trauma on cognitive outcomes in bipolar disorder.

Aims

Our study explores the effect of lifetime trauma on the level of vulnerability to psychosis and cognitive performance in participants with bipolar disorder.

Method

We evaluated lifetime trauma history in 236 participants with a diagnosis of bipolar disorder type 1 or 2, using the Structured Clinical Interview for DSM-IV and the Childhood Trauma Questionnaire. We classified trauma types based on the Substance Abuse and Mental Health Services Administration's concept of trauma, which characterises the type of experienced trauma (e.g. interpersonal and intentional, accidental or naturally occurring). Our primary outcome measures of interest were vulnerability to psychosis (Schizotypal Personality Questionnaire), cognitive performance (MATRICS Consensus Cognitive Battery) and social functioning (Social Adjustment Scale Self-Report).

Results

Multivariate analysis of covariance showed a significant effect of trauma type on the Schizotypal Personality Questionnaire cognitive–perceptual domain (F(3) = 6.7, P < 0.001). The no-trauma group had lower cognitive–perceptual schizotypal features compared with the accidental and intentional trauma (P < 0.001) and interpersonal and intentional trauma (P = 0.01) groups.

Conclusions

Our results highlight the need for careful trauma inquiry in patients with bipolar disorder, and consideration of how trauma-focused or -informed treatments may be an integral part of treatment planning to improve outcomes in bipolar disorder.

Bifactor Structure of the Schizotypal Personality Questionnaire Across the Schizotypy Spectrum

Despite widespread use in schizophrenia-spectrum research, uncertainty remains around an empirically supported and theoretically meaningful factor structure of the Schizotypal Personality Questionnaire (SPQ). Current identified structures are limited by reliance on exclusively nonclinical samples. The current study compared factor structures of the SPQ in a sample of 335 nonpsychiatric individuals, 292 schizotypy-spectrum individuals (schizophrenia, schizoaffective disorder, or schizotypal personality disorder), and the combined group (N = 627). Unidimensional, correlated, and hierarchical models were assessed in addition to a bifactor model, wherein subscales load simultaneously onto a general factor and a specific factor. The best-fitting model across samples was a two-specific factor bifactor model, consistent with the nine symptom dimensions of schizotypy as primarily a direct manifestation of a unitary construct. Such findings, for the first time demonstrated in a clinical sample, have broad implications for transdiagnostic approaches, including reifying schizotypy as a construct underlying diverse manifestations of phenomenology across a wide range of severity.

The Imbalanced Plasticity Hypothesis of Schizophrenia-Related Psychosis: A Predictive Perspective

A considerable number of studies have attempted to account for the psychotic aspects of schizophrenia in terms of the influential predictive coding (PC) hypothesis. We argue that the prediction-oriented perspective on schizophrenia-related psychosis may benefit from a mechanistic model that: 1) gives due weight to the extent to which alterations in short- and long-term synaptic plasticity determine the degree and the direction of the functional disruption that occurs in psychosis; and 2) addresses the distinction between the two central syndromes of psychosis in schizophrenia: disorganization and reality-distortion. To accomplish these goals, we propose the Imbalanced Plasticity Hypothesis - IPH, and demonstrate that it: 1) accounts for commonalities and differences between disorganization and reality distortion in terms of excessive (hyper) or insufficient (hypo) neuroplasticity, respectively; 2) provides distinct predictions in the cognitive and electrophysiological domains; and 3) is able to reconcile conflicting PC-oriented accounts of psychosis.

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.

The Relationship Between Multisensory Temporal Processing and Schizotypal Traits

Recent literature has suggested that deficits in sensory processing are associated with schizophrenia (SCZ), and more specifically hallucination severity. The DSM-5's shift towards a dimensional approach to diagnostic criteria has led to SCZ and schizotypal personality disorder (SPD) being classified as schizophrenia spectrum disorders. With SCZ and SPD overlapping in aetiology and symptomatology, such as sensory abnormalities, it is important to investigate whether these deficits commonly reported in SCZ extend to non-clinical expressions of SPD. In this study, we investigated whether levels of SPD traits were related to audiovisual multisensory temporal processing in a non-clinical sample, revealing two novel findings. First, less precise multisensory temporal processing was related to higher overall levels of SPD symptomatology. Second, this relationship was specific to the cognitive-perceptual domain of SPD symptomatology, and more specifically, the Unusual Perceptual Experiences and Odd Beliefs or Magical Thinking symptomatology. The current study provides an initial look at the relationship between multisensory temporal processing and schizotypal traits. Additionally, it builds on the previous literature by suggesting that less precise multisensory temporal processing is not exclusive to SCZ but may also be related to non-clinical expressions of schizotypal traits in the general population.

Attenuated Resting-State Functional Anticorrelation between Attention and Executive Control Networks in Schizotypal Personality Disorder

Exploring the disruptions to intrinsic resting-state networks (RSNs) in schizophrenia-spectrum disorders yields a better understanding of the disease-specific pathophysiology. However, our knowledge of the neurobiological underpinnings of schizotypal personality disorders mostly relies on research on schizotypy or schizophrenia. This study aimed to investigate the RSN abnormalities of schizotypal personality disorder (SPD) and their clinical implications. Using resting-state data, the intra- and inter-network of the higher-order functional networks (default mode network, DMN; frontoparietal network, FPN; dorsal attention network, DAN; salience network, SN) were explored in 22 medication-free, community-dwelling, non-help seeking individuals diagnosed with SPD and 30 control individuals. Consequently, while there were no group differences in intra-network functional connectivity across DMN, FPN, DAN, and SN, the SPD participants exhibited attenuated anticorrelation between the right frontal eye field region of the DAN and the right posterior parietal cortex region of the FPN. The decreases in anticorrelation were correlated with increased cognitive–perceptual deficits and disorganization factors of the schizotypal personality questionnaire, as well as reduced independence–performance of the social functioning scale for all participants together. This study, which links SPD pathology and social functioning deficits, is the first evidence of impaired large-scale intrinsic brain networks in SPD.

Exploring Identity Disturbance and Psychotic Spectrum Symptoms as Predictors of Borderline and Schizotypal Personality Disorders

INTRODUCTION

Borderline personality disorder (BPD) and schizotypal personality disorder (SPD) were introduced in DSM-III and retained in DSM-5 Section II. They often co-occur and some aspects of the clinical differentiation between the 2 diagnoses remain unclear (e.g., psychotic-like features and identity disturbance).

METHODS

The present study explored if self-reported identity disturbance and psychosis proneness could discriminate between the BPD and SPD DSM-5 diagnoses. All patients were interviewed with the Schedules for Clinical Assessment in Neuropsychiatry and the Structured Clinical Interview for DSM-5 Personality Disorders, and administered the Inventory of Personality Organization, Self-Concept and Identity Measure, Schizotypal Personality Questionnaire, Perceptual Aberration Scale, and the Magical Ideation Scale.

RESULTS

A total of 105 patients were initially assessed, 26 were excluded, and the final sample (N = 79) was composed of 34 BPD patients, 25 SPD patients, and 20 patients with co-occurring SPD and BPD. The BPD group (n = 34) was first compared with the pure SPD group (n = 25), and secondly with the total group of patients diagnosed with SPD (n = 25 + 20). Logistic regression analyses indicated that primitive defenses and disorganization best differentiated the BPD and the pure SPD group, while primitive defenses and interpersonal factor along with perceptual aberrations best differentiated the BPD and the total SPD group.

CONCLUSION

Identity disturbance did not predict the diagnostic groups, but BPD patients were characterized by primitive defenses, which are closely related to identity disturbance. Pure SPD was characterized by oddness/eccentricity, while the lack of specificity for cognitive-perceptual symptoms suggests that the positive symptoms do not differentiate BPD from SPD.

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.

[Structure of schizotypal traits in the Russian population]

Establishing the structure of schizotypal traits and its cross-cultural and demographic universality is an important condition for increasing the effectiveness of prognosis of schizophrenic spectrum disorders and basic research on their etiology. The present study aimed to explore the structure of schizotypal traits measured by the Schizotypal Personality Questionnaire (SPQ-74) in the Russian population. Exploratory and confirmatory factor analyses of the factor structure of SPQ-74 were performed using a sample of 1316 people of a wide age range. It is shown that, in the Russian population, the four-factor «paranoid» model of N. Stefanis et al. had the best fit for the data. The multivariate confirmatory analysis evidenced the gender invariance of the model.

The Attenuated Psychosis Syndrome and Facial Affect Processing in Adolescents With and Without Autism

BACKGROUND

Autism and schizophrenia spectrum disorders both represent severely disabling neurodevelopmental disorders with marked impairments in social functioning. Despite an increased incidence of psychosis in autism, and substantial overlap in symptoms and cognitive markers, it is unclear whether such phenotypes are specifically related to risk for psychosis or perhaps reflect more general, idiosyncratic autism traits. The attenuated psychosis syndrome (APS) is primarily defined by the presence of attenuated psychotic symptoms, which currently constitute the best and most-replicated clinical predictors of psychosis, and are common in clinical youth with and without autism. The aims of this study were to test the hypothesis that facial affect processing is impaired in adolescents with APS and to explore whether such deficits are more indicative of psychotic or autistic phenotypes on a categorical and dimensional level.

MATERIALS AND METHOD

Fifty-three adolescents with APS and 81 typically developing controls (aged 12-18) were included. The APS group consisted of adolescents with (n = 21) and without (n = 32) a diagnosis of autism spectrum disorder. Facial affect recognition was assessed with the Amsterdam Neuropsychological Tasks using a cascade model of cognitive processing, in which disturbances in "lower-level" cognitive abilities (pattern recognition), affect "higher-level" cognitive processes (face recognition and facial affect recognition). For associations with schizotypal and autistic-like traits the Schizotypal Personality Questionnaire and Social Communication Questionnaire were used in a confirmatory item factor analysis framework.

RESULTS

Contrary to expectation, APS in adolescents was not associated with impairments in pattern, face, or facial affect recognition. However, the APS group with autism spectrum disorder showed a general latency in response time to social and non-social stimuli. Dimensionally assessed schizotypal and autistic-like traits did not predict the accuracy or the speed of face or facial affect recognition.

CONCLUSION

Facial affect processing performance was not associated with APS in adolescence and represents an unlikely early vulnerability marker for psychosis. APS individuals with a more autistic-like profile were characterized by slower responses to social- and non-social stimuli, suggesting that the combined effect of APS and autism spectrum disorder on cognition is larger than for APS alone.

Personality and the Expression of Symptomatology in Schizophrenia and Bipolar Disorder

Researchers and clinicians have begun using dimensions rather than categories to classify psychopathology with a reliance on personality questionnaires to tap traits that can inform dimensional characterizations. A neglected concern is whether in severe psychopathology questionnaire-based assessments of personality reflect a lifetime propensity toward a diagnosis, as some personality-psychopathology models posit, or reflect the transient effects of current symptoms, as a complication model of personality-psychopathology would suggest. Accurate characterization of psychopathology is necessary to understand etiology and prescribe clinical care. We studied 127 adults with schizophrenia, schizoaffective, or bipolar disorder who completed well-validated measures of personality, current symptomatology, and lifetime psychopathology. We found that normative personality traits were related to current symptoms but unrelated to lifetime symptomatology, whereas the schizotypal trait of cognitive-perceptual distortions predicted lifetime psychosis severity. Questionnaire-based assessments of normative personality are likely affected by current symptom states and may fail to yield a stable characterization of psychopathology.

Metacognitively oriented psychotherapy for schizotypal personality disorder: A two-case series

Schizotypal personality disorder represents a broad range of maladaptive behaviour, which has been linked to both personality disorder and schizophrenia spectrum disorders; however, to date, little effort has been devoted to developing psychosocial treatment approaches to address it. In response, we conducted two case studies exploring the effects of two metacognitively oriented forms of psychotherapy: metacognitive interpersonal therapy and metacognitive reflection and insight therapy for patients with schizotypal personality disorder. We chose these two forms of therapy as they have been successfully delivered, respectively, to persons with other personality disorders and schizophrenia spectrum disorders. Both treatments consisted of weekly individual psychotherapy sessions over a period of 6 months. General symptoms were assessed during the first week of treatment, at treatment end and at 1 month following treatment using the Symptom Check List-90-Revised, while schizotypal traits were assessed with the Structured Clinical Interview for DSM-5. Both patients completed all sessions, and there were no reports of any adverse outcomes. Both patients achieved reliable change in symptoms (ranging from 4.98 to 9.81) and a significant reduction in schizotypal features. Results provide preliminary evidence of the feasibility of metacognitively oriented interventions for schizotypal personality disorder. © 2019 John Wiley & Sons, Ltd.

Severe childhood trauma and clinical and neurocognitive features in schizotypal personality disorder

OBJECTIVE

Literature suggests that childhood trauma increases vulnerability for schizophrenia-spectrum disorders, including schizotypal personality disorder (SPD). Yet, it remains unexplored whether childhood trauma predicts symptom load and the level of neurocognitive functioning in SPD.

METHOD

We included 225 individuals with SPD and 127 healthy controls. Childhood trauma was evaluated using the Childhood Trauma Questionnaire, and schizotypal traits were assessed using the Schizotypal Personality Questionnaire. Standard neurocognitive assessments covered six cognitive domains.

RESULTS

All types of reported childhood trauma were significantly associated with SPD, in a linear fashion. Severe sexual abuse showed the greatest magnitude of association with higher cognitive-perceptual load (e.g., ideas of reference, odd belief or magical thinking); severe emotional neglect was associated with interpersonal scores (e.g., excessive social anxiety, constricted affect) within the SPD group. SPD individuals who reported severe trauma showed worse cognitive functioning (i.e., working memory, verbal/visual learning and memory, as well as verbal fluency).

CONCLUSIONS

Particular severe childhood trauma types were associated with higher cognitive-perceptual and interpersonal symptoms in SPD, along with worse cognitive functioning. These findings highlight the need for clinicians to enquire about childhood trauma in SPD patients, since unaddressed early adverse experiences may carry long-term negative consequences.

The Schizotypal Personality Questionnaire - Child (SPQ-C): Psychometric properties and relations to behavioral problems with multi-informant ratings

The Schizotypal Personality Questionnaire (SPQ) is one of the most widely used screening tools for schizotypy in adults. The Schizotypal Personality Questionnaire-Child version (SPQ-C) was recently developed to assess schizotypy in children and has a similar three-factor structure to the adult SPQ (i.e., Cognitive-Perceptual, Interpersonal-Affective, and Disorganization). However, few studies to date have reported on the psychometric properties and the usefulness of the SPQ-C in Eastern populations, including Mainland China. This study presents the first psychometric assessment of the Chinese SPQ-C in Mainland China. Exploratory factor analysis and confirmatory factor analysis were used to assess the factor structure of the SPQ-C in 1668 children (M = 12.10, SD = 0.60 years) from the China Jintan Child Cohort Study. Our findings document a three-factor structure and partial measurement invariance across residential location and gender, replicating the psychometric properties of the SPQ-C in English. The Chinese SPQ-C further correlates with standard behavioral problems (i.e., Child Behavior Checklist, Youth Self-Report and Teacher Report Form), demonstrating construct validity and utility as a child psychopathology assessment tool. Our findings provide the first robust psychometric evidence for a three-factor structure of the Chinese SPQ-C in a large Mainland Chinese sample, and suggest that the SPQ-C is suitable as a screening tool for schizotypy in community children who may be at risk for behavioral problems and later psychosis.

Schizotypal Traits are Linked to Dopamine-Induced Striato-Cortical Decoupling: A Randomized Double-Blind Placebo-Controlled Study

The dopamine hypothesis of schizophrenia implies that alterations in the dopamine system cause functional abnormalities in the brain that may converge to aberrant salience attribution and eventually lead to psychosis. Indeed, widespread brain disconnectivity across the psychotic spectrum has been revealed by resting-state functional magnetic resonance imaging (rs-fMRI). However, the dopaminergic involvement in intrinsic functional connectivity (iFC) and its putative relationship to the development of psychotic spectrum disorders remains partly unclear-in particular at the low-end of the psychosis continuum. Therefore, we investigated dopamine-induced changes in striatal iFC and their modulation by psychometrically assessed schizotypy. Our randomized, double-blind placebo-controlled study design included 54 healthy, right-handed male participants. Each participant was assessed with the Schizotypal Personality Questionnaire (SPQ) and underwent 10 minutes of rs-fMRI scanning. Participants then received either a placebo or 200 mg of L-DOPA, a dopamine precursor. We analyzed iFC of 6 striatal seeds that are known to evoke modulation of dopamine-related networks. The main effect of L-DOPA was a significant functional decoupling from the right ventral caudate to both occipital fusiform gyri. This dopamine-induced decoupling emerged primarily in participants with low SPQ scores, while participants with high positive SPQ scores showed decoupling indifferently of the L-DOPA challenge. Taken together, these findings demonstrate that schizotypal traits may be the result of dopamine-induced striato-occipital decoupling.

Factor mixture analysis of paranoia in young people

BACKGROUND

Paranoid thoughts are relatively common in the general population and can increase the risk of developing mental health conditions. In this study, we investigate the latent structure of paranoia in a sample of young people.

METHODS

Cross-sectional survey; 243 undergraduate students (males: 44.9%) aged 24.3 years (SD 3.5). The participants completed the Green et al. Paranoid Thought Scales GPTS, a 32-item scale assessing ideas of social reference and persecution; the 12-item General Health Questionnaire (GHQ-12), and the 74-item Schizotypal Personality Questionnaire (SPQ). Confirmatory factor analysis (CFA) was used to confirm the two-factor structure of the GPTS. Factor mixture modeling analysis (FMMA) was applied to map the best combination of factors and latent classes of paranoia.

RESULTS

The GPTS showed excellent internal reliability and test-retest stability. Convergent validity was good, with stronger links with measures of ideas of reference and of suspiciousness than with other measures of psychosis-proneness. CFA showed excellent fit for the two-factor solution. FMMA retrieved a three-class solution with 176 subjects (72.5%) assigned to a baseline class, 54 (22.2%) to a "suspicious and mistrustful" class, and 13 (5.3%) to a "paranoid thinking" class. Compared to the baseline class, the other two classes had a higher risk of psychological distress and psychosis-proneness.

CONCLUSIONS

The latent structure of paranoid thinking in young people appears dimensional. Although caution is advised when generalizing from studies on college students, screening for paranoid ideation in young people who complain about psychological distress might prove useful to prevent the development of severe and potentially debilitating conditions.

Gender moderates the relationship between stressful life events and psychopathology: Findings from a national study

BACKGROUND

While data suggest a strong relationship between trauma exposure and psychopathology, less research has investigated relationships between psychopathology and stressful life events more broadly, and how these relationships may differ by gender.

AIM

To examine strengths of associations between stressful life events and psychiatric disorders (i.e., past-year Axis I and lifetime Axis II, per DSM-IV) and how they may differ by gender.

METHODS

Data from Wave 1 of the National Epidemiological Survey on Alcohol and Related Conditions (NESARC; n = 43,093) were analyzed using chi-square tests and multinomial logistic regression analyses. Participants were categorized according to occurrence of stressful life events (low, moderate, and high).

RESULTS

Women as compared to men were more likely to report moderate (p < 0.0001) or high occurrence stressful life events (p < 0.0001). Increasing experiences of stressful life events were associated with increasing odds of most past-year Axis I and lifetime Axis II disorders in both gender groups, with the largest odds typically observed in association with more frequent stressful life events. Associations between stressful life events and multiple psychiatric disorders were stronger in women compared to men.

CONCLUSIONS

Stressful life events are associated with multiple Axis I and Axis II psychiatric disorders in both men and women. This relationship is moderated by gender. Screening female patients who endorse significant stressors for mood, anxiety, and substance-use problems might be particularly important. The stronger associations in women between stressful life events and personality disorders in particular warrant further investigation.

A reassessment of the higher-order factor structure of the German Schizotypal Personality Questionnaire (SPQ-G) in German-speaking adults

The Schizotypal Personality Questionnaire (SPQ) is a widely-used self-report instrument for the assessment of schizotypal personality traits. However, the factor structure of scores on English and non-English translations of the SPQ has been a matter of debate. With little previous factorial evaluation of the German version of the SPQ (SPQ-G), we re-assessed the higher-order factor structure of the measure. A total of 2,428 German-speaking adults from Central Europe (CE) and the United Kingdom (UK) completed the SPQ-G. Confirmatory factor analysis - testing proposed 2-, 3-, and 4-factor models of SPQ-G scores - indicated that the 4-factor solution had best fit. Partial measurement invariance across cultural group (CE and UK) and sex was obtained for the 4-factor model. Further analyses showed CE participants had significantly higher scores than UK participants on one schizotypal facet. These results suggest that scores on the SPQ-G are best explained in terms of a higher-order, 4-factor solution in German migrant and non-migrant adults.

The Network Structure of Schizotypal Personality Traits

Elucidating schizotypal traits is important if we are to understand the various manifestations of psychosis spectrum liability and to reliably identify individuals at high risk for psychosis. The present study examined the network structures of (1) 9 schizotypal personality domains and (2) 74 individual schizotypal items, and (3) explored whether networks differed across gender and culture (North America vs China). The study was conducted in a sample of 27001 participants from 12 countries and 21 sites (M age = 22.12; SD = 6.28; 37.5% males). The Schizotypal Personality Questionnaire (SPQ) was used to assess 74 self-report items aggregated in 9 domains. We used network models to estimate conditional dependence relations among variables. In the domain-level network, schizotypal traits were strongly interconnected. Predictability (explained variance of each node) ranged from 31% (odd/magical beliefs) to 55% (constricted affect), with a mean of 43.7%. In the item-level network, variables showed relations both within and across domains, although within-domain associations were generally stronger. The average predictability of SPQ items was 27.8%. The network structures of men and women were similar (r = .74), node centrality was similar across networks (r = .90), as was connectivity (195.59 and 199.70, respectively). North American and Chinese participants networks showed lower similarity in terms of structure (r = 0.44), node centrality (r = 0.56), and connectivity (180.35 and 153.97, respectively). In sum, the present article points to the value of conceptualizing schizotypal personality as a complex system of interacting cognitive, emotional, and affective characteristics.

The effect of being left home alone at age 3 years on schizotypy and antisocial behavior at ages 17 and 23 years

OBJECTIVE

Negative home environments are associated with both schizophrenia-spectrum disorders and crime, but whether this is due to the social or cognitive sequelae of such environments is unclear. This study investigates the effect of early home environments on adult mental health.

METHOD

Using data from the Mauritius Child Health Project, a multiple time-point prospective study where all children born in 1969 in two towns (Quatre Bornes and Vacaos) were recruited at age 3 years (N = 1794), a group of children left home alone at age 3 (n = 34) were compared to children cared for by siblings/relatives (n = 222), or by mothers (n = 1498) on antisocial behavior and schizotypal personality at ages 11, 17, and 23 years.

RESULTS

Home alone children showed higher scores on psychotic behavior and conduct disorder at age 17, and also schizotypal personality and crime at 23 years compared to the other groups. No negative behavioral or cognitive effects were observed at age 11. Findings were not accounted for by social adversity or ethnicity and appear to be 'sleeper effects' in that they do not emerge until later adolescence and into adulthood.

CONCLUSIONS

Findings appear to be the first to show the negative effects of dual-parental daytime absence on adult schizotypy and crime, a finding that cannot be accounted for by verbal and spatial cognitive impairments. Results suggest an early common psychosocial denominator to the two comorbid conditions of antisocial behavior and schizotypy.

Down the rabbit hole: assessing the influence of schizotypy on the experience of the Barbie Doll Illusion

INTRODUCTION

"Body swapping" illusions have been used to explore factors contributing to the experience of "owning" an artificial body. Preliminary research indicated that those people diagnosed with schizophrenia experience more vivid illusions of this kind than do "normal" individuals.

OBJECTIVES

Here, we explored whether participants who rated themselves "high" on the cognitive-perceptual factor of the Schizotypal Personality Questionnaire (SPQ) experienced a more compelling sense of immersion in a variation of the body swapping illusion: The Barbie Doll Illusion. We also hypothesised that these individuals would experience a change in size perception when immersed in the illusion.

METHOD

Forty-four participants wore a pair of Head-Mounted Display goggles connected to a video-camera, and thus a doll's body replaced their own body in their visual field. In two conditions, touch was either applied synchronously or asynchronously to the doll's and each participant's leg. After each condition, participants filled out a questionnaire relating to their experience in the illusion. When both conditions were completed, they filled out the SPQ.

RESULTS

Our first hypothesis was confirmed, which suggested that people with higher cognitive-perceptual SPQ scores do indeed experience a more compelling Barbie Doll Illusion; however, our second hypothesis was not supported.

CONCLUSION

Our study demonstrated, for the first time, that proneness to the positive and interpersonal factors of schizotypy in a normal population is sufficient to produce a compelling sense of swapping bodies.

Comparisons of schizotypal traits across 12 countries: Results from the International Consortium for Schizotypy Research

BACKGROUND

Schizotypal traits are expressions of underlying vulnerability to psychotic disorders which have a potential impact on mental health status, neurocognition, quality of life, and daily functioning. To date, little research has examined epidemiologic landscape of schizotypal traits at the cross-national level. Our aim was to study the expression of schizotypal traits by sex, age, and country in a combined sample gathered from 12 countries.

METHODS

A total of 27,001 participants completed the Schizotypal Personality Questionnaire (SPQ). The mean age of participants was 22.12 (SD=6.28); 37.5% (n=10,126) were males.

RESULTS

Schizotypal traits varied according to sex, age, and country. Females scored higher than males in the positive dimension, whereas males scored higher in the disorganization dimension. By age, a significant decrease in the positive schizotypal traits was observed. Epidemiological expression of schizotypal traits varied by country. Moreover, several interactions by sex, age, and country were found.

CONCLUSIONS

This pattern is similar to those found in patients with psychosis and psychotic-like experiences. These findings provide new insights and the opportunity to explore the phenotypic expression of schizotypal traits at cross-national level.

Quick Identification of the Risk of Psychosis: The Italian Version of the Prodromal Questionnaire-Brief

Background:

Diagnosing people during the prodromal phase of an incipient psychosis can improve the chance of better outcome. In busy clinical settings, the ideal tool is a brief, easy-to-complete self-report questionnaire.

Objective:

To test the psychometric properties of the Italian version of one of the most used screening tools for the identification of the risk of psychosis, the Prodromal Questionnaire-Brief (PQ-B).

Methods:

Cross-sectional design. A convenience sample of college students was enrolled via snowball procedure (n=243; men: 45%). After understanding and signing the consent form, the participants received a booklet containing the following questionnaires: the 21-item Prodromal Questionnaire-Brief (PQ-B); the 12-item General Health Questionnaire (GHQ-12), and the 74-item Schizotypal Personality Questionnaire (SPQ). Receiver operating characteristic (ROC) analysis was used to assess the capacity of the PQ-B to identify individuals at risk of psychosis as independently defined based on the combination of GHQ-12 and SPQ thresholds.

Results:

The Italian version of the PQ-B revealed good internal consistency, test-retest reliability, and adequate convergent and divergent validity. The Youden method retrieved a cut-off = 7 for the PQ-B frequency score and a cut-off = 22 for the PQ-B distress score. Both PQ-B scores had a perfect (99%) negative predictive value.

Conclusion:

The PQ-B is a promising screening tool in two-stage protocols. The major advantage of the PQ-B is to exclude cases that are unlikely to be at risk of psychosis.

Brief assessment of schizotypal traits: A multinational study

The Schizotypal Personality Questionnaire-Brief (SPQ-B) was developed with the aim of examining variations in healthy trait schizotypy, as well as latent vulnerability to psychotic-spectrum disorders. No previous study has studied the cross-cultural validity of the SPQ-B in a large cross-national sample. The main goal of the present study was to analyze the reliability and the internal structure of SPQ-B scores in a multinational sample of 28,426 participants recruited from 14 countries. The mean age was 22.63years (SD=7.08; range 16-68years), 37.7% (n=10,711) were men. The omega coefficients were high, ranging from 0.86 to 0.92 for the total sample. Confirmatory factor analysis revealed that SPQ-B items were grouped either in a theoretical structure of three first-order factors (Cognitive-Perceptual, Interpersonal, and Disorganized) or in a bifactor model (three first-order factors plus a general factor of schizotypal personality). In addition, the results supported configural but not strong measurement invariance of SPQ-B scores across samples. These findings provide new information about the factor structure of schizotypal personality, and support the validity and utility of the SPQ-B, a brief and easy tool for assessing self-reported schizotypal traits, in cross-national research. Theoretical and clinical implications for diagnostic systems, psychosis models, and cross-national mental health strategies are derived from these results.

Assessment of Cognition and Personality as Potential Endophenotypes in the Western Australian Family Study of Schizophrenia

Phenotypic heterogeneity is a major barrier to understanding the genetic architecture underlying schizophrenia. Incorporating endophenotypes is one way to reduce heterogeneity and facilitate more powerful genetic analysis. Candidate endophenotypes require systematic assessment against endophenotype criteria, and a ranking of their potential utility for genetic analysis. In this study we assess 20 cognitive and personality measures in a sample of 127 families with at least 2 cases of schizophrenia per family (n = 535) plus a set of 30 control families (n = 121) against 4 endophenotype criteria: (a) be associated with the illness but not be a part of its diagnosis, (b) be heritable, (c) co-segregate with the illness in families, and (d) be found in unaffected relatives at a higher rate than in the general population. The endophenotype ranking score (endophenotype ranking variable [ERV]) was used to rank candidate endophenotypes based on their heritability and genetic correlation with schizophrenia. Finally, we used factor analysis to explore latent factors underlying the cognitive and personality measures. Evidence for personality measures as endophenotypes was at least equivalent to that of the cognitive measures. Factor analysis indicated that personality and cognitive traits contribute to independent latent dimensions. The results suggest for this first time that a number of cognitive and personality measures are independent and informative endophenotypes. Use of these endophenotypes in genetic studies will likely improve power and facilitate novel aetiological insights.

Psychometric properties of the Malay Schizotypal Personality Questionnaire: Measurement invariance and latent mean comparisons in Malaysian adults

INTRODUCTION

The Schizotypal Personality Questionnaire (SPQ) is a widely used self-report measurement instrument for the assessment of schizotypal personality traits. However, the factor structure of the SPQ has been a matter of some debate. As a contribution to this debate, we examined the factor structure of the SPQ in Malaysian adults.

METHOD

A total of 382 Malaysian adults completed a Malay translation of the SPQ. Confirmatory factory analysis was used to examine the fit of 3- and 4-factor solutions for the higher-order dimensionality of the SPQ. Ethnic invariance for the best-fitting model was tested at the configural, metric, and scalar levels, and a multivariate analysis of variance was used to examine sex and ethnicity differences in domain scores.

RESULTS

The 4-factor model provided a better fit to the data than did the 3-factor model. The 4-factor model also demonstrated partial measurement invariance across ethnic groups. Latent mean comparisons for sex and ethnicity revealed a number of significant differences for both factors, but effect sizes were small.

DISCUSSION

The 4-factor structure of the SPQ received confirmatory support and can be used in Malay-speaking populations.

Developmental Aspects of Schizotypy and Suspiciousness: a Review

Purpose of the Review

This review identifies the early developmental processes that contribute to schizotypy and suspiciousness in adolescence and adulthood. It includes the most recent literature on these phenomena in childhood.

Recent Findings

The early developmental processes that affect schizotypy and paranoia in later life are complex. In contrast to existing studies of psychiatric patients and clinical/nonclinical adult populations, the study of schizotypy and suspiciousness in young children and adolescents is possible due to new child-appropriate dimensional assessments. New assessments and the advancement of technology (e.g., virtual reality in mental health) as well as statistical modeling (e.g., mediation and latent-class analyses) in large data have helped identified the developmental aspects (e.g., psychosocial, neurocognitive and brain factors, nutrition, and childhood correlates) that predict schizotypy and suspiciousness in later life.

Summary

Prospective longitudinal designs in community youths can enhance our understanding of the etiology of schizophrenia-spectrum disorders and, in the future, the development of preventive interventions by extending adult theories and interventions to younger populations.

The structure of schizotypal personality traits: a cross-national study

BACKGROUND

Schizotypal traits are considered a phenotypic-indicator of schizotypy, a latent personality organization reflecting a putative liability for psychosis. To date, no previous study has examined the comparability of factorial structures across samples originating from different countries and cultures. The main goal was to evaluate the factorial structure and reliability of the Schizotypal Personality Questionnaire (SPQ) scores by amalgamating data from studies conducted in 12 countries and across 21 sites.

METHOD

The overall sample consisted of 27 001 participants (37.5% males, n = 4251 drawn from the general population). The mean age was 22.12 years (s.d. = 6.28, range 16-55 years). The SPQ was used. Confirmatory factor analysis (CFA) and Multilevel CFA (ML-CFA) were used to evaluate the factor structure underlying the SPQ scores.

RESULTS

At the SPQ item level, the nine factor and second-order factor models showed adequate goodness-of-fit. At the SPQ subscale level, three- and four-factor models displayed better goodness-of-fit indices than other CFA models. ML-CFA showed that the intraclass correlation coefficients values were lower than 0.106. The three-factor model showed adequate goodness of fit indices in multilevel analysis. The ordinal α coefficients were high, ranging from 0.73 to 0.94 across individual samples, and from 0.84 to 0.91 for the combined sample.

CONCLUSIONS

The results are consistent with the conceptual notion that schizotypal personality is a multifaceted construct and support the validity and utility of SPQ in cross-cultural research. We discuss theoretical and clinical implications of our results for diagnostic systems, psychosis models and cross-national mental health strategies.

The Schizotypal Personality Questionnaire-Brief lacks measurement invariance across three countries

The Schizotypal Personality Questionnaire-Brief (SPQ-B) is a commonly-used tool for measuring schizotypal personality traits and due to its wide application, its cross-cultural validity is of interest. Previous studies suggest that the SPQ-B either has a three- or four-factor structure, but the majority of studies have been conducted in Western contexts and little is known about the psychometric properties of the scale in other populations. In this study factorial invariance testing across three cultural contexts-Australia, China and Chile was conducted. In total, 729 young adults (Mean age = 23.99 years, SD = 9.87 years) participated. Invariance testing did not support the four-factor model across three countries. Confirmatory Factor Analyses revealed that neither the four- nor three-factor model had strong fit in any of the settings. However, in comparison with other competing models, the four-factor model showed the best for the Australian sample, while the three-factor model was the most reasonable for both Chinese and Chilean samples. The reliability of the SPQ-B scores, estimated with Omega, ranged from 0.86 to 0.91. These findings suggest that the SPQ-B factors are not consistent across different cultural groups. We suggest that these differences could be attributed to potential confounding cultural and translation issues.

Personality Inventory for DSM-5 (PID-5) in Clinical Versus Nonclinical Individuals: Generalizability of Psychometric Features

The Personality Inventory for Diagnostic and Statistical Manual of Mental Disorders–Fifth Edition (PID-5) was developed for the assessment of pathological traits in clinical settings. However, most research on the PID-5 is derived from nonclinical samples. To date, the comparability and generalizability of PID-5 constructs across nonclinical and clinical samples have not been adequately investigated. Therefore, we investigated the measurement invariance, five-factor structure, and factor correlations across clinical and nonclinical samples. The clinical sample ( n = 598) comprised patients with nonpsychotic disorders (81% women; mean age = 28.95), whereas a matched nonclinical sample ( n = 598) comprised community-dwelling individuals (81% women; mean age = 29.59). Measurement invariance was analyzed using a 13-step, two-group exploratory structural equation modeling approach. The results demonstrated acceptable psychometric properties for both samples and supported strong measurement invariance across the groups at the domain level.