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Schizophrenia spectrum disorders are debilitating conditions which cause adverse consequences for people with the disorder, their relatives, and general society. Impairments in social cognition, especially in emotion processing, have been found to be a primary determinant of poor community functioning. Cognitive remediation can reduce social cognitive dysfunction when it is provided early in illness progression and individually tailored. Nonetheless, current diagnostic methods for schizophrenia spectrum disorders, such as clinical interviews, are not entirely reliable, can be impractical, and often depend upon the progression of symptoms to ensure accuracy. Functional near-infrared spectroscopy (fNIRS) is an emerging neuroimaging technique that may be applied to identify biomarkers of emotion processing impairment in the early stages of schizophrenia. fNIRS overcomes many limitations of current assessment methods, is practically advantageous compared to alternative neuroimaging techniques, and is well suited for measuring parts of the prefrontal cortex (PFC), a region established in the cognitive processing of emotion. Nonetheless, before fNIRS can be considered for use in practice, its capacity to reliably detect activation during emotion processing and distinguish between high and low schizotypy needs to be evaluated. This thesis aims to determine the capacity of fNIRS for detecting prefrontal activation during emotion processing and identify differences in activation between people with high and low schizotypy., Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Applied Psychology, Griffith Health, Full Text

Background: Mentalization is an umbrella concept defined as the ability to interpret one's and others' mental states. Previous studies have hypothesized that mentalization may be a crucial resilience factor that significantly moderates the likelihood of developing psychotic disorders in individuals with both state and trait risk factors for the illness. Purpose: The study reviews the role of mentalizing abilities (e.g., reflective functioning, Theory of Mind (ToM), and metacognition) in young adults with At-Risk Mental States (ARMS) and schizotypal traits. Specifically, the objective is to include articles that (a) evaluate the links between low mentalizing and both state (ARMS/CHR) and trait (schizotypy) risk for psychosis (b) compare the differences in mentalizing abilities between individuals with ARMS, schizotypy, full-blown psychosis, and healthy controls. Method: Electronic databases (PsycINFO, PubMed, Scopus, and Google Scholar) were used to search for articles, while Rayyan was employed to facilitate the screening and selection of studies. Eligible studies are original English-language; peer-reviewed research articles on populations that met validated risk diagnostic criteria for psychosis, ARMS, and healthy controls; empirical studies evaluating the association or differences between psychotic risk and mentalizing abilities. Non-English language studies, the ones not considering state or trait risk for psychosis, and qualitative studies were excluded. After the application of the PRISMA checklist and the inclusion and exclusion criteria previously mentioned, 10 articles were extracted. The systematic review has been registered on Prospero (CRD42023397594). Results: Low levels of reflective functioning and metacognition may predict a transition to psychosis. In addition, reflective functioning and metacognitive impairments are associated with attenuated psychotic symptoms in both state risk groups and in non-clinical individuals with schizotypal traits. Conc

The aim of the study is to test a model specifying the relations between personality traits, war-related traumas, PTSD and depression, as well as the measurement aspects of the model. This study was carried out in hospital on 400 male participants. Five-Factor Model of personality was complemented by a recently proposed trait Disintegration representing proneness to psychotic-like experiences/behaviors in the general population. The proposed model had excellent fit, despite its complexity. The results show that PTSD or depression symptoms after traumas are largely related to the number of traumas, Neuroticism, Extraversion, and Disintegration, and their different configurations and quantities. Disintegration turned out to be one of the most important dispositional correlates of depression and PTSD, but also of trauma exposure. © 2021

Sensory deficits are a feature of autism and schizophrenia, as well as the upper end of their non-clinical spectra. The mismatch negativity (MMN), an index of pre-attentive auditory processing, is particularly sensitive in detecting such deficits; however, little is known about the relationship between the visual MMN (vMMN) to facial emotions and autism and schizophrenia spectrum symptom domains. We probed the vMMN to happy, sad, and neutral faces in 61 healthy adults (18–40 years, 32 female), and evaluated their degree of autism and schizophrenia spectrum traits using the Autism Spectrum Quotient (AQ) and Schizotypal Personality Questionnaire (SPQ). The vMMN to happy faces was significantly larger than the vMMNs to sad and neutral faces. The vMMN to happy faces was associated with interpersonal difficulties as indexed by AQ Communication and Attention to Detail subscales, and SPQ associated with more interpersonal difficulties. These data suggest that pre-attentive processing of positive affect might be more specific to the interpersonal features associated with autism and schizophrenia. These findings add valuable insights into the growing body of literature investigating symptom-specific neurobiological markers of autism and schizophrenia spectrum conditions.

The Hierarchical Taxonomy of Psychopathology consortium aims to develop a comprehensive self-report measure to assess psychopathology dimensionally. The current research describes the initial conceptualization, development, and item selection for the thought disorder spectrum and related constructs from other spectra. The thought disorder spectrum is defined primarily by the positive and disorganized traits and symptoms of schizophrenia-spectrum disorders. The Thought Disorder Sub-Workgroup identified and defined 16 relevant constructs and wrote 10 to 15 items per each construct. These items were administered, along with detachment and mania items, to undergraduates and people with serious mental illness. Three hundred and sixty-five items across 25 scales were administered. An exploratory factor analysis of the scale scores suggested a two-factor structure corresponding to positive and negative symptoms for two samples. The mania scales loaded with the positive factor, while the detachment scales loaded with the negative factor. Item-level analyses resulted in 19 preliminary scales, including 215 items that cover the range of thought disorder pathology, and will be carried forward for the next phase of data collection/analysis.

La investigación alrededor del constructo esquizotipia responde a un campo de extenso desarrollo desde su denominación décadas atrás, que incluye los trastornos del espectro de la esquizofrenia (TEE) y al trastorno de personalidad esquizotípica (TPE), aunque persisten controversias marcadas por la dificultad de establecer consensos definitivos. La necesidad de consolidar los avances en la evaluación de este campo volvió operativa la formulación de esta investigación, se realizó una revisión de la literatura internacional, que contempló 65 trabajos de investigación publicados en la última década (2010-2020). A partir de una síntesis del conocimiento acumulativo, se definieron las herramientas de evaluación válidas y en uso, para su caracterización psicométrica, clínica y de personalidad, además de las implicaciones clínicas encontradas en sus resultados. También se discute el avance de nociones como el continuum de la psicosis y la taxonomía, finalmente se dedica un apartado a un modelo y herramienta multidimensional., Introduction: research carried out regarding the psychological concept of schizotypy responds to a field of extensive development since its conceptualization decades ago, which includes schizophrenia spectrum disorders (SSD) and schizotypal personality disorder (SPD). However, controversies still persist marked by the difficulty of establishing definitive consensus. Objective: the research purpose aimed to synthesize the empirical evidence involved in the use of various methodologies and tools for understanding schizotypy. Methodology: A systematic review was carried out in the following databases: Web of Science, Scopus, PubMed, Taylor and Francis, Wiley, Science Direct, Google Scholar, and PsycNet. By using the PRISMA guidelines, 65 studies published in the last decade (2010-2020) were discriminated. Results: The synthesis of cumulative knowledge made it possible to define schizotypy as an integrating multidimensional construct and to identify valid assessment tools in use, in its psychometric, clinical, and personality characterizations. Discussion/Conclusions: Clinical implications found in these reports are addressed, as well as notions of the continuum of psychoses, taxonomic, and multidimensional models.

BACKGROUND: Autism spectrum disorder (ASD) and schizotypal personality disorder can be difficult to distinguish. Deficits in social relationships and social interaction, present in both conditions, are known to impair quality of life. The aim of the present study was to investigate if schizotypal symptoms affect quality of life among adults diagnosed with autism spectrum disorder and to study the association between schizotypy and autistic traits among them. METHODS: Participants diagnosed with autism spectrum disorder (n = 110) completed questionnaires exploring schizotypy (Schizotypal Personality Questionnaire - Brief Revised (SPQ-BR)), autistic traits (The Ritvo Autism, Asperger Diagnostic Scale-Revised Screen 14 items), anxiety and depression (The Hospital Anxiety and Depression scale) and quality of life (Brunnsviken Brief Quality of Life Scale and the European quality of life index version 5D). RESULTS: Schizotypy was found to be associated with anxiety, depressive and autistic symptoms, and poor quality of life. Although schizotypy was a predictor for impaired quality of life, this relationship was mediated by symptoms of anxiety and depression, plausibly inherent to autism. Autistic traits were positively associated with all higher order constructs of the SPQ-BR, i.e. positive and negative schizotypy, disorganization and social anxiety, as well as with poor quality of life. CONCLUSIONS: There is considerable overlap between schizotypy and autism that needs to be considered in research. Prominent schizotypal traits in people with ASD may constitute an endophenotype coinciding with a particularly poor quality of life. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03570372 : Internet-based Treatment for Adults with Autism Spectrum Disorder (MILAS)., Funding agencies:Örebro UniversityÖrebro University Hospital Research Foundation Nyckelfonden OLL-785311Forskningskommitten Region Örebro County OLL-785501 OLL-736321 OLL-833131 OLL-887401Örebro Regional Council, ALF grant OLL-935396 OLL-879651Regional Research Council in Mid Sweden RFR-556731

Non-reductive ideation is characterized by a tendency to attribute causality to non-physical powers and mysterious forms of intelligent agency such as conspiracist ideation, belief in specific conspiracy theories, and belief in the paranormal. Scholars have identified numerous individual correlates of non-reductive ideation but do not examine shared patterns across multiple predictors to determine subtypes of individuals with different psychological profiles. We address this gap by considering a large set of predictors in a diverse cross-section of the US public (N=792) to uncover latent subtypes of individuals with varying tendencies toward non-reductive ideation. Schizotypal and neurotic tendencies were the strongest predictors of non-reductive ideation, while sociopolitical identity (e.g., political ideology) contributed little explanatory power. We find five distinct latent classes distinguished by: schizotypal and paranoid ideation, alienated skepticism toward people/society, and a negative sense of self. We discuss these results in light of previous findings and suggest directions for future research.

Studying epistemically unwarranted beliefs (EUB) is relevant at basic, applied, and social levels. However, EUB scales validated in Spain are scare. Consequently, we aimed to develop and validate a scale of this kind. One thousand four hundred and sixty participants answered to a preliminary version of the questionnaire. Exploratory and confirmatory factor analyses revealed the final form of PEUBI: a 36-item instrument with five related factors (Superstitions, Occultism and Pseudoscience, Traditional Religion, Extraordinary Life Forms, and Conspiracy Theories). The results showed that the items were little affected by social desirability bias. PEUBI factor scores showed good internal consistency (estimates between .85 and .97), test-retest reliability (estimates between .75 and .93), and convergent-divergent validity. Sociodemographic differences were also explored, observing lower levels of EUB in men, elders, from pure sciences and technology, and atheists. In conclusion, PEUBI is a valid and reliable psychometric instrument to assess paranormal, pseudoscientific and conspiracy beliefs in Spanish adults.

Previous studies have brought conflicting results regarding the effects of valence and arousal in visual word processing. Some authors have pointed to participants' individual differences as one of the possible explanations for these inconsistencies. The main aim of the present research was to examine whether participants' individual differences in the level of epistemically unwarranted beliefs (EUB) contribute to these conflicting results. Therefore, participants who varied in their level of paranormal, pseudoscientific and conspiracy beliefs (assessed by self-report measures) performed a lexical decision task (LDT) and a recognition memory task. Linear mixed-effects models over LDT response times revealed that the effects of words' emotional content (both valence and arousal) were modulated by the degree of individuals' EUB. In addition, signal detection theory analyses showed that in the recognition task (but not in the LDT) response bias became more liberal as individuals' EUB increased. These patterns of effects were not general to all EUB instances. The obtained results highlight the need to consider participants' individual differences in affective word processing and signal detection. In addition, this study reveals some basic psychological mechanisms that would underlie EUB, a fact that has both theoretical and applied relevance.

People with schizophrenia or subclinical schizotypal traits exhibit impaired recognition of facial expressions. However, it remains unclear whether the detection of emotional facial expressions is impaired in people with schizophrenia or high levels of schizotypy. The present study examined whether the detection of emotional facial expressions would be associated with schizotypy in a non-clinical population after controlling for the effects of IQ, age, and sex. Participants were asked to respond to whether all faces were the same as quickly and as accurately as possible following the presentation of angry or happy faces or their anti-expressions among crowds of neutral faces. Anti-expressions contain a degree of visual change that is equivalent to that of normal emotional facial expressions relative to neutral facial expressions and are recognized as neutral expressions. Normal expressions of anger and happiness were detected more rapidly and accurately than their anti-expressions. Additionally, the degree of overall schizotypy was negatively correlated with the effectiveness of detecting normal expressions versus anti-expressions. An emotion–recognition task revealed that the degree of positive schizotypy was negatively correlated with the accuracy of facial expression recognition. These results suggest that people with high levels of schizotypy experienced difficulties detecting and recognizing emotional facial expressions.

Antecedentes: la evidencia empírica ha demostrado que la esquizotipia es un constructo útil para analizar y comprender los trastornos psicóticos. Sin embargo, todavía quedan por resolver varias cuestiones. Método: en esta revisión selectiva y crítica se abordan algunas limitaciones, se discuten interrogantes y se comentan direcciones futuras de trabajo. Resultados: en primer lugar, se presenta una delimitación conceptual y se comenta la evidencia acumulada en diferentes estudios y niveles de análisis en el campo de la esquizotipia. A continuación, se examinan nuevos modelos psicopatológicos, como el modelo de red, y se presentan las diferentes herramientas desarrolladas y validadas para su evaluación. Seguidamente, se abordan algunas inquietudes metodológicas de fondo y se presentan nuevas técnicas y procedimientos psicométricos, como la evaluación ambulatoria y bioconductual. También se analizan algunos de los problemas inherentes en la investigación entre países y culturas. Finalmente, se establecen las conclusiones y se abordan nuevos desafíos y direcciones futuras de investigación. Conclusiones: esta revisión selectiva y crítica plantea que es necesario continuar trabajando en la construcción de un modelo científico sólido y refutable e incorporar nuevas pruebas científicas en el campo de la esquizotipia., Background: Empirical evidence suggests that schizotypy is a useful construct for analyzing and understanding psychotic disorders. However, several issues remain to be resolved. Method: This selective, critical review, addresses some questions and limitations, and discusses future directions of work. Results: First, we present a conceptual outline and discuss the evidence from translational and interdisciplinary studies on schizotypy. Next, we examine and discuss newer analytical and methodological approaches, including network and machine learning approaches. We also discuss newer psychometric identification approaches, such as those using biobehavioral and ambulatory assessment. Next, we review recent cross-cultural studies in schizotypy research. Finally, we identify new challenges and directions and draw conclusions. Conclusions: This selective, critical review suggests that new methods can contribute to the construction of a solid scientific model of schizotypy as a risk construct.

The influence of psychosocial stressors on psychosis risk has usually been studied in isolation and after the onset of the disorder, potentially ignoring important confounding relationships or the fact that some stressors that may be the consequence of the disorder rather than preexisting. The study of subclinical psychosis could help to address some of these issues. In this study, we investigated whether there was (i) an association between dimensions of subclinical psychosis and several psychosocial stressors including: childhood trauma, self-reported discrimination experiences, low social capital, and stressful life experiences, and (ii) any evidence of environment-environment (ExE) interactions between these factors. Data were drawn from the EUGEI study, in which healthy controls (N = 1497) and siblings of subjects with a psychotic disorder (N = 265) were included in six countries. The association between psychosocial stressors and subclinical psychosis dimensions (positive, negative and depressive dimension as measured by the Community Assessment of Psychic Experiences (CAPE) scale) and possible ExE interactions were assessed using linear regression models. After adjusting for sex, age, ethnicity, country, and control/sibling status, childhood trauma (beta for positive dimension: 0.13, negative: 0.49, depressive: 0.26) and stressful life events (positive: 0.08, negative: 0.16, depressive: 0.17) were associated with the three dimensions. Lower social capital was associated with the negative and depression dimensions (negative: 0.26, depressive: 0.13), and self-reported discrimination experiences with the positive dimension (0.06). Our findings are in favor of independent, cumulative and non-specific influences of social adversities in subclinical psychosis in non-clinical populations, without arguments for E x E interactions.

Introduction: Schizophrenia symptomatology exists on a continuum ranging from subclinical psychotic-like experiences in the general population (schizotypy) to full-blown clinical symptoms. High schizotypy individuals are at an increased risk for developing clinical diagnoses, yet previous work has not investigated key neural abnormalities of schizophrenia in these samples. Methods: To ensure findings are informative for clinical risk, we only recruited individuals scoring at the extreme low/high end of the Schizotypy Personality Questionnaire. 27 high schizotypy (HS) and 26 low schizotypy (LS) individuals to take part in two functional magnetic resonance imaging (fMRI) tasks assessing social learning. Participants also underwent a resting state fMRI and a magnetic resonance spectroscopy scan. Results: HS subjects, compared to LS, present with abnormal learning of social information. HS overestimate the volatility of social cues and are slower to learn about global changes in social context. Furthermore, HS subjects show reduced neural activity in the dopaminergic midbrain and increased frontal cortex activity in response to prediction errors during social learning. HS subjects also present with a reduced resting-state functional connectivity between hippocampus and striatum/thalamus and with reduced GABA and Glu metabolite levels in the prefrontal cortex. Discussion: HS subjects, representing the earliest risk for clinical transition to schizophrenia, already present with key neural abnormalities implicated in progression, mainly abnormal hippocampal functioning and abnormal GABA/Glu levels. These results encourage investigations of HS to facilitate a comprehensive view of risk/protective factors for clinical transition. The results also show that HS subjects already present with abnormal hierarchical learning as seen in clinical samples. HS subjects neutrally underweight prediction errors indicating an improper proce

The phenomenon of somatosensory attenuation describes the perception that self-generated touch feels weaker than externally generated touch of identical intensity. Previous studies have shown that besides intensity, self-generated touches feel less pleasant and less ticklish than identical externally generated touches. However, previous studies did not systematically assess attenuation across a range of stimuli that can elicit intensity, pleasantness, and ticklishness more efficiently. This thesis aims to replicate these previous observations across a range of tactile stimuli of different intensities and velocities and investigate whether people who attenuate their self-generated touches to a greater extent do so for all aforementioned qualities. Previous studies have shown that participants with lower levels of somatosensory attenuation have more schizotypal personality traits. Twelve volunteers participated in three perceptual tasks where they received touches on their sole generated either by a robot(External) or the participants(Self). Following the strokes, participants had to rate the sensation from 0(not at all) to 100(extremely). For the intensity task, we manipulated the intensity of the applied forces (1,2,3,4N). For the pleasantness and ticklishness tasks, we manipulated the velocity of the applied strokes (0.3,1,10,30cm/s). After the tasks, participants completed a Schizotypal Personality Questionnaire (SPQ). Significant somatosensory attenuation was observed in all tasks, but for specific, not all, stimuli: forces of 4N in terms of intensity, strokes of 1cm/s in terms of pleasantness, and strokes of 10cm/s and 30cm/s in terms of ticklishness. These results suggest that the ability to suppress the tactile consequences of self-generated touch occurs in all three tactile qualities.

Background: Formal thought disorder was constitutively linked to the original concept of schizophrenia and has since been one of central features supporting its diagnosis. Bleuler considered formal thought disorder as a fundamental symptom of schizophrenia among other fundamental symptoms, including ego disorders. The contemporary concept of self-disorder represents a more developed, nuanced, and systematic approach to disturbances of self-experience than the Bleulerian concept of ego disorders. As fundamental symptoms, on Bleuler's account, are persistently present in every case, an association between these symptoms could be expected. The purpose of this study was to examine the association between self-disorder and formal thought disorder. Methods: A sample of 94 diagnostically heterogeneous patients was examined for formal thought disorder using clinical rating and a proverb test. The proverb test was analyzed for two different aspects of formal thought disorder: literal responses and bizarre responses. The sample was comprehensively assessed for psychopathology, including self-disorder as measured with the Examination of Anomalous Self-Experience scale. Results: The patients, who provided bizarre responses, had a higher level of self-disorder, more negative symptoms, lower level of social functioning, and lower level of intelligence. Bizarre answers aggregated in patients diagnosed within the schizophrenia spectrum compared with patients outside the schizophrenia spectrum. We found moderate correlations between the two measures of formal thought disorder (clinically rated and bizarre responses) and self-disorder (0.454 [p < 0.01] and 0.328 [p < 0.01]). Literal responses did not differ between diagnostic groups and also did not correlate with bizarre responses. Specificity of bizarre responses for a diagnosis within schizophrenia spectrum was 86.89%, whereas sensitivity was 40.85%. Conclusion: The close relation between formal thought disorder and self

OBJECTIVE: Social deficits are already exhibited by people at risk for schizophrenia-spectrum disorders. Technological advances have made passive detection of social deficits possible at granular levels. METHOD: In this real-world study, we tested if schizotypy status (high/low) predicted two types of social behavior: (1) being around other people; and (2) actively socializing with others. We also examined if schizotypy influences relationships between social behavior and affect using subjective and objective instruments. RESULTS: Our findings revealed that socializing with others was significantly decreased in the high schizotypy group. Positive affect increased in social situations and predicted later social behavior in those low, but not high, in schizotypy. CONCLUSION: Decreased social behavior in schizotypy may be explained, in part, by these individuals being less incentivized than their peers to pursue social situations. Future studies should test this explanation in larger samples exhibiting elevated positive, negative, and disorganized schizotypy traits.

Dezintegracija predstavlja svojevrsnu operacionalizaciju šizotipije, crte ličnosti koja se odnosi na sklonost ka doživljavanju propsihotičnih iskustava kod pripadnika opšte populacije, i koja leži na kontinumu sa šizofrenijom. Zbog metodoloških prednosti u odnosu na ispitivanje klinički obolelih, istraživači sve češće ispituju pripadnike opšte populacije radi identifikovanja riziko faktora za obolevanje od šizofrenije. Nastojeći da odgonetnu mehanizme koje stoje u osnovi kognitivnih deficita kod šizotipije, posredstvom primene različitih kognitivnih zadataka, istraživači raspravljaju o postojanju teškoća u procesiranju konteksta i brzini obrade informacija. Zbog nedovoljno istražene oblasti, varijabilnosti postojećih podataka i činjenice da se o pomenutim deficitima uglavnom izvode zaključci na osnovu primene pojedinačnih kognitivnih zadataka, ovo istraživanje je imalo za cilj da ispita postojanje teškoća u procesiranju konteksta i brzini obrade informacija posredstvom primene više kognitivnih zadataka i time doprinese podrobnijem razumevanju ove oblasti. Za merenje procesiranja konteksta su korišćena tri zadatka: Ebinghausova iluzija, Diz-Rediger-Mekdermotova paradigma i AX test kontinuiranog izvođenja, dok je za merenje brzine obrade informacija korišćeno četiri zadatka: retroaktivno maskiranje, zadatak šifra i zadaci prostog i izbornog vremena reakcije. Kao prediktori u istraživanju korišćeni su sociodemografski podaci, inteligencija (merena Ravenovim progresivnim matricama), bazične crte ličnosti (merene HEXACO modelom) i dezintegracija (merena upitnikom DELTA). Celokupna baterija je postavljena na platformu za online testiranje Total Assessment. Ispitivanje je sprovedeno u kontrolisanim uslovima. U istraživanju je učestvovalo 215 pripadnika studentske populacije (31 % muškaraci i 69 % žene, prosečne starosti 22.65, SD = 4.24). U odnosu na osnovni cilj istraživanja i postavljenu istraživačku hipotezu, potvrđeno je da dezintegracija u odnosu na bazične crte lično, Disintegration is a kind of operationalization of schizotypy, personality traits related to the propensity for experiencing pro-psychotic experiences in the general population, which is located on the same continuum with schizophrenia. Due to its methodological advantages over the investigations on clinical population, researchers increasingly investigate members of the general population in order to identify risk factors for developing schizophrenia. Trying to establish the mechanisms that underlie cognitive deficits in schizotypy, through the application of various cognitive tasks, the researchers argue about the existence of difficulties in processing context and information processing speed. Due to insufficiently researched area, the variability of the existing data, and the fact that conclusions about deficits are performed mainly based on the usage of single cognitive tasks, the aim of this study is to explore the existence of difficulties in processing context and information processing speed through by using a few cognitive tasks and thus contribute to a more detailed understanding of this field. The context processing is measured by using three tasks: Ebinghaus illusion, Deese-Roediger-McDermott paradigm and AX continuous performance task, while the processing speed is measured by four tasks: backward masking task, digit-symbol task and tasks of simple and choice reaction time. As predictors were used a socio-demographic data, intelligence (measured by Raven's progressive matrices), a basic personality traits (measured by HEXACO model) and disintegration (measured by DELTA questionnaire). The entire battery is placed on a platform for online testing Total Assessment. The study was conducted in a controlled environment. A total of 215 students participated in survey (31% men and 69% women, mean age 22.65, SD = 4.24). Relative to the main aim of the research and the proposed research hypotheses, it was confirmed that the disintegration, beyond basic personali

OBJECTIVES: The main goal of the present study was to analyze the network structure of schizotypy dimensions in a representative sample of adolescents from the general population. Moreover, the network structure between schizotypy, mental health difficulties, subjective well-being, bipolar-like experiences, suicide ideation and behavior, psychotic-like experiences, positive and negative affect, prosocial behavior, and IQ was analyzed. METHOD: The study was conducted in a sample of 1,506 students selected by stratified random cluster sampling. The Oviedo Schizotypy Assessment Questionnaire, the Personal Wellbeing Index-School Children, the Paykel Suicide Scale, the Mood Disorder Questionnaire, the Strengths and Difficulties Questionnaire, the Prodromal Questionnaire-Brief, the Positive and Negative Affect Schedule for Children Shortened Version, and the Matrix Reasoning Test were used. RESULTS: The estimated schizotypy network was interconnected. The most central nodes in terms of standardized Expected Influence (EI) were 'unusual perceptual experiences' and 'paranoid ideation'. Predictability ranged from 8.7% ('physical anhedonia') to 52.7% ('unusual perceptual experiences'). The average predictability was 36.27%, implying that substantial variability remained unexplained. For the multidimensional psychosis liability network predictability values ranged from 9% (estimated IQ) to 74.90% ('psychotic-like experiences'). The average predictability was 43.46%. The results of the stability and accuracy analysis indicated that all networks were accurately estimated. CONCLUSIONS: The present paper points to the value of conceptualizing psychosis liability as a dynamic complex system of interacting cognitive, emotional, behavioral, and affective characteristics. In addition, provide new insights into the nature of the relationships between schizotypy, as index of psychosis liability, and the role played by risk and protective factors.

There is a well-established relationship between cannabis use and psychosis, although the exact nature of this relationship is not fully understood. Recent studies have observed significant genetic overlap between a diagnosis of schizophrenia and lifetime cannabis use. Expanding on this work, the current study aimed to examine whether genetic overlap also occurs for subclinical psychosis (schizotypy) and cannabis use, as well as examining the phenotypic association between the traits. Phenotypic correlations were calculated for a variety of schizotypy and cannabis phenotypes in the UK Biobank (UKB), and single nucleotide polymorphism (SNP)-based heritability estimates and genetic correlations were calculated for these UKB phenotypes as well as for several other variables taken from recent genomewide association studies. Positive phenotypic correlations were observed between 11 out of 12 pairs of the cannabis use and schizotypy phenotypes (correlation range.05-.18), indicating a robust association between increased symptoms of schizotypy and cannabis use. SNP-based heritability estimates for two schizotypy phenotypes remained significant after multiple testing correction: social anhedonia (h2SNP =.08, SE =.02, N = 4025) and ever seen an unreal vision (h2SNP =.35, SE =.10, N = 150,717). Finally, one significant genetic correlation was observed between schizotypy and cannabis use, a negative correlation between social anhedonia and number of times used cannabis (rg = -.30, p =.012). The current study suggests the relationship between cannabis use and psychosis is also seen in subclinical symptoms of psychosis, but further research with larger samples is needed to determine the biological mechanisms underlying this association.

Creativity is hugely important in our everyday lives. Understanding what makes some people more creative than others is not just important in traditional creative fields. Creative problem solving is the key to solving all significant challenges we face as a society, including but not limited to technological, political and environmental challenges. Mental illness, in both popular culture and in psychological science, have long been linked to creative thought. Many eminent creatives, both past and current, attribute their success to their mental illness. For example, in schizophrenia, the grandiose thinking and florid hallucinations that characterise this disorder may be supportive of creative thinking. However, schizophrenia is characterised by severe cognitive deficits that, according to models of creativity, would be disadvantageous to creative thinking. Schizotypy is a personality trait that is characterised by some features of schizophrenia (unusual thinking, poor interpersonal communication), but is not accompanied by the same severe cognitive deficits seen in schizophrenia. Based on this view, it is reasonable to assume that people high on schizotypal traits may be more creative than those who are low on schizotypal traits. While there a number of studies examining this relationship, findings are inconsistent, with effect sizes ranging from -.42 to .8. In my thesis, I explored a) whether there was a relationship between schizotypy and creativity and b) whether that relationship could be explained by underlying differences in cognitive processing (associative processing and executive control). I predicted that positive schizotypy in particular (typified by unusual thinking, superstitious beliefs) would be positively correlated with schizotypy in three different measures of creativity (two performance based tasks and one self-report measure) in two different samples of participants. In Chapters 3 + 4, I tested the relationship between schizotypy and creativity u

[Objectives] The main goal of the present study was to analyze the network structure of schizotypy dimensions in a representative sample of adolescents from the general population. Moreover, the network structure between schizotypy, mental health difficulties, subjective well-being, bipolar-like experiences, suicide ideation and behavior, psychotic-like experiences, positive and negative affect, prosocial behavior, and IQ was analyzed., [Method] The study was conducted in a sample of 1,506 students selected by stratified random cluster sampling. The Oviedo Schizotypy Assessment Questionnaire, the Personal Wellbeing Index–School Children, the Paykel Suicide Scale, the Mood Disorder Questionnaire, the Strengths and Difficulties Questionnaire, the Prodromal Questionnaire–Brief, the Positive and Negative Affect Schedule for Children Shortened Version, and the Matrix Reasoning Test were used., [Results] The estimated schizotypy network was interconnected. The most central nodes in terms of standardized Expected Influence (EI) were ‘unusual perceptual experiences’ and ‘paranoid ideation’. Predictability ranged from 8.7% (‘physical anhedonia’) to 52.7% (‘unusual perceptual experiences’). The average predictability was 36.27%, implying that substantial variability remained unexplained. For the multidimensional psychosis liability network predictability values ranged from 9% (estimated IQ) to 74.90% (‘psychotic-like experiences’). The average predictability was 43.46%. The results of the stability and accuracy analysis indicated that all networks were accurately estimated., [Conclusions] The present paper points to the value of conceptualizing psychosis liability as a dynamic complex system of interacting cognitive, emotional, behavioral, and affective characteristics. In addition, provide new insights into the nature of the relationships between schizotypy, as index of psychosis liability, and the role played by risk and protective factors.

Schizotypy, characterised as a cluster of personality traits, provides a unifying framework for understanding risk, aetiology, developmental trajectory, and prognosis for psychopathology. Besides reflecting a latent liability for psychosis, schizotypy also allows investigation of individual differences beyond clinical settings. Impaired social functioning has been well-documented as a feature of psychiatric disorders and is posited to present before illness onset, remain stable over illness course, and persist long after symptomatic remission. Despite the transdiagnostic nature of loneliness and its likely frequent co-occurrence with schizotypal traits, the role of loneliness and poor social functioning in schizotypy research has been scarce. The broad aim of this thesis is to elucidate the underlying mechanisms of social functioning in individuals with schizotypy, social anhedonia and psychotic-like experiences (PLEs). One of the more specific aims was the examination of the role of facial expressions of emotion, loneliness, and social support in their relationships with schizotypy.

Shizotipija je konstrukt koji se koristi kako bi se opisala grupa osoba sa simptomima koji ne ispunjavaju kriterijume za postavljanje dijagnoze shizofrenije, ali imaju sličnosti sa ovim kompleksnim i heterogenim psihiajtrijskim oboljenjem. MKB-10 opisuje shizotipiju kao privremeno stanje (shizotipalni poremećaj), dok je DSM-5 opisuje kao trajniji poremećaj (shizotipalni poremećaj ličnosti). S obzirom da se shizotipija prostire kroz normalnu, supkliničku i kliničku populaciju, temeljno teorijsko razumevanje ovog koncepta može biti od pomoći prilikom razvijanja mera procene shizotipije. Do sada, najveći deo psihometrijske evaluacije shizotipije bazirao se na varijetetima individualnih razlika (poremećaja) ličnosti. Ovaj članak se fokusira na evoluciju termina shizotipije, na razumevanje ovog fenomena, mogućnosti psihometrijske procene u skladu sa trenutnim modelima ličnosti i na klinička razmatranja koja bi dovela do poboljšane detekcije i intervencije u ovoj oblasti., Schizotypy is a construct used to describe a group of persons with symptoms which do not fulfill criteria for schizophrenia, but have some similarities with this complex and heterogeneous psychiatric disorder. ICD-10 describes schizotypy as a state (schizotypal disorder), while DSM-5 labels it as a trait marker (schizotypal personality disorder). Considering how schizotypy encompasses through the normal, subclinical and clinical population, a thorough theoretical understanding of this concept could be helpful in developing measures of assessment. So far, most of the tools for psychometric evaluation of schizotypy have focused only on abnormal personality. The present article focuses on the evolution of the term schizotypy, its current understanding, the possibilities of psychometric assessment in relation to contemporary constructs of personality and on clinical considerations for improved detection and intervention in this field.

Eysenck's model of personality (PEN) was one of the most influential personality models in the 20th century. A unique characteristic of this model is the claim of psychosis-proneness being incorporated into it as one of its three basic traits - Psychoticism. The main goal of this systematic review and meta-analysis is to find out the associations between PEN traits and a diverse set of operationalizations of psychosis-proneness (PP). We set the benchmark for assuming their distinctness to a correlation coefficient amounting to 0.40. A systematic review has been conducted, yielding 350 correlations of interest. By computing inverse sampling variance weighted mean correlation coefficients, we found the following associations between psychosis-proneness and Psychoticism, Extraversion, and Neuroticism, respectively: 0.21, -0.09, and 0.30. All prediction intervals around the three mean effect sizes do include zero, suggesting that psychosis-proneness is only marginally captured by the PEN model. Moderator analyses further demonstrated this distinctness and the lack of phenotypic validity of the Psychoticism scale/construct.

The study objective was to examine childhood adversity in association with intra-individual changes and inter-individual differences in subclinical psychosis in a representative community cohort over a 30-year period of observation. We analyzed two psychosis syndromes derived from the SCL-90-R – schizotypal signs and schizophrenia nuclear symptoms – in 335 participants. Participants were repeatedly assessed between 1978 (around age 20) and 2008 (around age 50). We focused specifically on inter-individual differences and intra-individual changes over time by applying structural equation modeling, generalized linear models, and generalized estimating equations. Several weak inter-individual differences revealed that increased schizotypal signs are related to various childhood adversities, such as being repeatedly involved in fights and parents having severe conflicts among themselves. We also found a significant positive association between schizotypal signs and the total number of adversities a subject experienced. This pointed toward a modest dose-response relationship. The intra-individual change in schizotypal signs over time was rather weak, although some adjustment did occur. In contrast, inter-individual schizophrenia nuclear symptoms were mainly unrelated to childhood adversity. However, some striking intra-individual changes in distress were noted over time, especially those linked with severe punishment and the total adversity score. In conclusion, we have confirmed previous positive findings about the association between childhood adversity and subsequent subclinical psychosis symptoms: An increase in adversity is weakly related to an increase of the psychosis symptom load. However, depending on the kind of adversity experienced the psychosis symptom load decreases gradually in adult life.

Maternal depressed mood during pregnancy is common, but studies on the offspring of antenatally depressed mothers, with a long follow-up, are scarce. The aim was to study whether the adult offspring of antenatally depressed mothers are at an elevated risk of psychoses, depression, bipolar disorder, antisocial and borderline personality disorder, and schizotypal and affective traits. Parental severe mental disorder was considered as both a genetic and environmental risk factor for mental disorders. The data are based on the unselected, prospective, population-based Northern Finland 1966 Birth Cohort of 12,058 live-born children. The data were collected beginning from pregnancy and ending mid-adulthood. The mothers were asked about their mood during pregnancy at the antenatal clinic at 24–28 gestational weeks. Of the mothers, 13.9% rated themselves as depressed (11.8%) or very depressed (2.1%) during pregnancy. Parents’ severe, hospital-treated mental disorders, and the cohort members’ mental disorders were identified mainly by using the Finnish Care Register for Health Care. In this study, the adult offspring of antenatally depressed mothers had an increased risk of depression, and the male offspring for antisocial personality disorder, compared to cohort members without antenatally depressed mothers. The offspring with both maternal antenatal depressed mood and parental severe mental disorder had a markedly elevated risk of schizophrenia and depression, compared to cohort members without one or both of the risk factors. This is the first study where the offspring of antenatally depressed mothers were followed till mid-adulthood, also taking into account parental severe mental disorders. Based on the findings, the prevention of and early intervention in antenatal depression, especially in families with severe mental illness, might present an opportunity to reduce the risk of mental disorders in the offspring., Tiivistelmä Äitien raskausajan masennus on yleistä, mutta pitkiä seurantatutkimuksia raskausaikana masentuneiden äitien lapsista on vähän. Tutkimuksen tavoitteena oli selvittää, onko raskausaikana masentuneiden äitien aikuisilla jälkeläisillä kohonnut riski sairastua skitsofreniaan, masennukseen, kaksisuuntaiseen mielialahäiriöön, epäsosiaaliseen tai epävakaaseen persoonallisuushäiriöön, ja ilmeneekö heillä enemmän skitsotyyppisiä tai affektiivisia piirteitä. Vanhempien vakavien mielenterveydenhäiriöiden katsottiin olevan sekä mahdollisia geneettisiä että ympäristöön liittyviä riskitekijöitä jälkeläisten mielenterveyshäiriöille. Tutkimus perustuu yleisväestöön pohjautuvaan, prospektiiviseen Pohjois-Suomen vuoden 1966 syntymäkohorttiin, johon kuuluu 12 058 elävänä syntynyttä lasta. Kohortin jäseniä on seurattu sikiöajalta keski-ikään, aina 49 ikävuoteen saakka. Äitien raskaudenaikaista mielialaa tiedusteltiin raskausviikoilla 24–28 neuvolassa. 13,9 % äideistä raportoi mielialansa masentuneeksi (11,8 %) tai hyvin masentuneeksi (2.1%) raskausaikana. Vanhempien vakavat mielenterveydenhäiriöt ja kohortin jäsenten mielenterveyshäiriöt selvitettiin pääosin hoitoilmoitusrekisteritiedoista. Tutkimuksessa raskaudenaikana masentuneiden äitien lapsilla havaittiin kohonnut depressioriski sekä kohonnut epäsosiaalisen persoonallisuushäiriön riski miehillä, verrattuna kohortin jäseniin, joiden äitien mieliala ei ollut masentunut raskausaikana. Kohortin jäsenillä, joiden äideillä oli raskausajan masennusta ja toisella vanhemmista vakava mielenterveyshäiriö, oli kohonnut riski sairastua skitsofreniaan ja depressioon, verrattuna heihin, joilla oli vain yksi tai ei kumpaakaan näistä riskitekijöistä. Tämä on ensimmäinen tutkimus, jossa raskausaikana masentuneiden äitien lapsia on seurattu keski-ikään saakka, huomioiden myös vanhempien vakavat mielenterveydenhäiriöt. Tutkimuksen tulosten perusteella äidin raskausajan masennusoireiden varhaisen tunnistamisen ja hoidon voitaisiin ajatella

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., Funding Agencies:National Institute of Environmental Health Sciences National Institutes of Health R01-ES-018858 K02-ES-019878 K01-ES015877

A large literature has demonstrated an abnormal sense ofagency (SOA) in schizophrenic individuals. One limitation ofsuch studies is that they focus exclusively on cognitive orperceptual judgments, thus failing to address affective aspectsof SOA. In our recent work, we have used instrumentaldivergence – the distance between outcome probabilitydistributions associated with available actions – as a formalmeasure of agency, demonstrating an influence of this noveldecision variable on behavioral choice preferences andassociated neural computations in neurotypical adults. Here,we show that the preference for high instrumental divergence(i.e., for high-agency environments) is significantlymodulated by individual differences in positive and negativeschizotypy dimensions. Implications for future assessmentsof clinical populations are discussed.

Evidence is growing that persons along the schizophrenia spectrum, i.e., those who also display subclinical psychotic symptoms, exhibit deficits across a broad range of neuropsychological domains. Because sex differences in the association between cognitive deficits and psychosis have thus far been mostly neglected, we believe that ours is the first study specifically focused upon those differences when examining the relationship between subclinical psychosis and processing speed. Using a sample of 213 persons from the general population from Zurich, Switzerland, psychotic symptoms were assessed with three different questionnaires including the Schizotypal Personality Questionnaire, an adaptation of the Structured Interview for Assessing Perceptual Anomalies, and the Paranoia Checklist. Processing speed was assessed with the WAIS digit-symbol coding test. Two higher-order psychosis domains were factor-analytically derived from the various psychosis subscales and then subjected to a series of linear regression analyses. The results demonstrate that in both men and women associations between subclinical psychosis domains and processing speed were weak to moderate (β ranging from − 0.18 to − 0.27; all p < 0.05). However, we found no sex-differences in the interrelation of subclinical psychosis and processing speed (ΔR2 < 0.005; p > 0.30). In conclusion, it appears that sex differences in psychosis manifest themselves only at the high end of the continuum (full-blown schizophrenia) and not across the sub-threshold range. The small magnitude of the effects reported herein conforms to the etiopathology of the disorder. Since schizophrenia and related disorders from the spectrum are assumed to be multifactorial diseases, it follows that many etiological components of small effect are involved.

The latent structure of schizotypy and psychosis-spectrum symptoms remains poorly understood. Furthermore, molecular genetic substrates are poorly defined, largely due to the substantial resources required to collect rich phenotypic data across diverse populations. Sample sizes of phenotypic studies are often insufficient for advanced structural equation modeling approaches. In the last 50 years, efforts in both psychiatry and psychological science have moved toward (1) a dimensional model of psychopathology (eg, the current Hierarchical Taxonomy of Psychopathology [HiTOP] initiative), (2) an integration of methods and measures across traits and units of analysis (eg, the RDoC initiative), and (3) powerful, impactful study designs maximizing sample size to detect subtle genomic variation relating to complex traits (the Psychiatric Genomics Consortium [PGC]). These movements are important to the future study of the psychosis spectrum, and to resolving heterogeneity with respect to instrument and population. The International Consortium of Schizotypy Research is composed of over 40 laboratories in 12 countries, and to date, members have compiled a body of schizotypy- and psychosis-related phenotype data from more than 30000 individuals. It has become apparent that compiling data into a protected, relational database and crowdsourcing analytic and data science expertise will result in significant enhancement of current research on the structure and biological substrates of the psychosis spectrum. The authors present a data-sharing infrastructure similar to that of the PGC, and a resource-sharing infrastructure similar to that of HiTOP. This report details the rationale and benefits of the phenotypic data collective and presents an open invitation for participation.

OBJECTIVE: The aim of the present study is to examine the heterogeneity of attenuated psychotic symptoms (PS) and related personality factors using a cluster analytic approach. METHOD: A large sample of participants from the general population was evaluated in terms of attenuated symptomatology (psychotic and affective) and two personality factors: encoding style and impulsivity traits. RESULTS: Cluster analysis emphasized the existence of five independent clusters: High Psychosis, High Positive, High Negative, High Impulsive-Low Psychosis, and Low Psychosis. Cluster comparisons demonstrated that the personality factors and PS are differentially involved in the clusters. CONCLUSIONS: The present study demonstrated that reliable and relatively distinct clusters of individuals from the general population can be identified based on established PS and related personality factors. The fact that a variety of profiles was observed contributes to a better understanding of the nature of the heterogeneity characterizing PS and has clear theoretical and clinical implications.

Several studies have demonstrated that expression of a psychosis phenotype can be observed below the threshold of its clinical detection. To date, however, no conceptual certainty has been reported for the validity and reliability of sub-clinical psychosis. Our main objectives were to assess the prevalence rates and severity of various psychosis symptoms in a representative community sample. Furthermore, we wanted to analyze which latent factors are depicted by several currently used psychosis questionnaires. We also examined how those latent factors for sub-clinical psychosis are linked to psychosocial factors, normal personality traits, and coping abilities related to chronic stress. Most of the eight subscales from the Paranoia Checklist and the Structured Interview for Assessing Perceptual Anomalies had a very similar type of distribution, i.e., an inverse Gaussian (Wald) distribution. This supported the notion of a continuity of psychotic symptoms, which we would expect to find for continuously distributed symptoms within the general population. Sub-clinical psychosis can be reduced to two different factors – one representing odd beliefs about the world and odd behavior, and the other one representing anomalous perceptions (such as hallucinations). Persons with odd beliefs and behavior are under greater burden and more susceptible to psychosocial risks than are persons with anomalous perceptions. These sub-clinical psychosis syndromes are also related to stable personality traits. In conclusion, we obtained strong support for the notion that there is no natural cut-off separating psychotic illness from good health. Sub-clinical psychosis of any kind is not trivial because it is associated with various types of social disability.

The current thesis investigates individual differences that are associated with insight. Traditionally, this research question has been tested by measuring the associations between measures of individual difference of interest (e.g., fluid intelligence, creativity, etc.), and the ability to solve “insight problems.” We firstly explore the result of this trend (Chapter 3), investigating the role of convergent thinking, divergent thinking, and schizotypy in insight and non-insight problem solving. Results indicate that convergent thinking (the ability to solve problems) is the strongest and most reliable predictor of insight problem-solving abilities. Two questions are raised by the use of accuracy as an indicator of insight processes: to what extent are aha experiences and accuracy related, and how reliably can insight problems elicit experiences of insight. We investigate the relationship between problem-solving success (accuracy) and insight (Chapter 4), and the reliability of insight problems in eliciting insight (Chapter 5). We found a positive relationship between correctly solved insight problems and ratings of insight phenomenology (e.g., aha experience, pleasure). While the tendency for insight problems to elicit insight was marginally reliable, this reliability was substantially greater when calculating reliability of ratings of aha experience in correctly solved problems only. The importance of accuracy in experiencing insight emphasised an issue that was consistent throughout the thesis: the necessity for problem-solving abilities in order to solve insight problems and thus elicit the feeling of insight. In Chapter 6, we explore the role of divergent thinking, convergent thinking, and schizotypy in the tendency to report the experience of insight in the problem- solving process. We found that including accuracy in the model as a predictor of aha experience shifted the ability of particular individual difference variables (i.e., divergent thinking and posit

Objective The aim of the present study is to examine the heterogeneity of attenuated psychotic symptoms (PS) and related personality factors using a cluster analytic approach. Method A large sample of participants from the general population was evaluated in terms of attenuated symptomatology (psychotic and affective) and two personality factors: encoding style and impulsivity traits. Results Cluster analysis emphasized the existence of five independent clusters: High Psychosis, High Positive, High Negative, High Impulsive-Low Psychosis, and Low Psychosis. Cluster comparisons demonstrated that the personality factors and PS are differentially involved in the clusters. Conclusions The present study demonstrated that reliable and relatively distinct clusters of individuals from the general population can be identified based on established PS and related personality factors. The fact that a variety of profiles was observed contributes to a better understanding of the nature of the heterogeneity characterizing PS and has clear theoretical and clinical implications.

The Clinical Assessment Interview for Negative Symptoms (CAINS) was designed in accordance with the recent theory and research in social affective neuroscience and to address the psychometric and conceptual limitations of other instruments assessing negative symptoms. The present study aimed to provide a large-scale validation of the CAINS in China and examine its applicability and validity evidence across the schizophrenia spectrum. Using confirmatory factor analysis, our results replicated the original findings in the US development samples that the CAINS possesses a stable 2-factor structure, namely "motivation/pleasure" and "expression". We also found significant correlations between the CAINS and other negative symptom measures. The CAINS demonstrated good discriminant validity in differentiating negative symptoms in people with schizophrenia, nonpsychotic first-degree relatives and people with social anhedonia. People with schizophrenia exhibited significantly higher CAINS subscale scores than first-degree relatives and healthy controls. In addition, first-degree relatives had higher "motivation/pleasure" scores than healthy controls. The "motivation/pleasure" subscale scores of individuals with social anhedonia were also significantly higher than healthy controls.

Delayed motor developmental milestones have been reported to be associated with schizophrenia in previous studies, but no study has examined the relationship between early motor developmental milestones and schizotypy. We have examined this relationship in a prospective birth cohort. In the Northern Finland Birth Cohort 1966, data on 9 early motor developmental milestones were collected prospectively from visits to child welfare centers, and data on adult schizotypy were collected through a questionnaire (N = 4557–4674). Positive schizotypy was measured by the Perceptual Aberration Scale (PAS), negative schizotypy was measured by Physical Anhedonia Scale (PhAS) and Social Anhedonia Scale (SAS). Three related scales were included: Schizoidia Scale (SCHD), Hypomanic Personality Scale (HPS), and Bipolar II Scale (BIP2). We examined the milestone–schizotypy associations before and after excluding cases of schizophrenia from this population-based sample. Hierarchical regression analyses adjusted for covariates and separately for both genders were performed. In men, each extra month of delay in achievement of touching thumb with index finger, sitting unsupported, standing up, walking with support, or walking unsupported was associated with an increase in PAS, PhAS, or SCHD scores, or decrease in BIP2 score (P < 0.05). In women, each extra month of delay in achievement of turning from back to tummy was associated with an increase in PhAS and SAS scores (P < 0.05). Schizotypy is associated with delayed motor developmental milestones in early-life, but there is some heterogeneity with regards to types of milestones and gender. These findings suggest delayed motor development confers risk across the continuum of schizophrenia syndrome.

Schizotypy is regarded as a trait vulnerability marker for psychosis. The study of this personality trait in otherwise healthy samples affords opportunities to research potential co-occurring risk factors for psychosis, without the confounds inherent to psychiatric diagnosis. The current thesis is focused on the expression of schizotypy alongside neurodevelopmental, language and affective risk factors for psychosis. The specific risk factors investigated were neurological soft signs (NSS), semantic processing, affective temperament, and psychological distress. Additionally, this thesis investigated whether propensity to hallucinate had an effect on these factors when combined with psychometric schizotypy. Language abnormalities have also been extensively researched in schizotypy and along the psychosis continuum. Given the overlap between the psychosis continuum and language abnormalities such as those seen in dyslexia, this thesis also sought to determine whether risk factors for psychosis are also present in a dyslexia sample. This thesis is made up of a combination of five studies, some of which are published and submitted manuscripts, with the remainder being manuscripts in preparation for publication. Study One investigated the relationship between schizotypy and distress. Affective temperament was found to mediate this relationship. Contrary to predictions hallucination predisposition was not found to exert significant effects on either the direct or indirect relationship between schizotypy and distress. Study Two explored whether NSS are expressed differently in those with high and low levels of schizotypy and additionally, whether hallucination predisposition interacts with this effect. Results indicated that those with high overall schizotypy express significantly more NSS, and that hallucination predisposition has additive effects on this association. Study Three looked at the expression of NSS in a dyslexia sample. It was found that individuals with dysle