Oxford-Liverpool Inventory Of Feelings Research Articles

Schizotypy, affective temperaments and anhedonia in bipolar depression.

"Schizotypy" is a term describing personality traits reflected in emotional, perceptual and cognitive styles. Affective temperaments are trait-like features which were observed to be stable in time and predispose to mood disorders. The purpose of this study was to examine relationship between schizotypal features, affective temperaments and anhedonia in patients with bipolar depression. 54 patients with bipolar depression were included in the study. Participant were administered the following psychometric tools: Dimensional Anhedonia Rating Scale (DARS), Snaith-Hamilton Pleasure Scale (SHAPS), Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE), Temperament Evaluation of Memphis, Pisa, Paris, and San Diego Autoquestionnaire (TEMPS-A), and Quick Inventory of Depressive Symptomatology - Self-Report (QIDS-SR). Correlations between the variables were calculated and linear regression models were built. Only hyperthymia (affective temperament) and introvertive anhedonia (schizotypal domain) were statistically significantly correlated with anhedonia. In regression models, introvertive anhedonia predicted higher whereas hyperthymic features lower severity of anhedonia (measured by the SHAPS scale). Hyperthymic features are protective and introvertive anhedonia is a risk factor for consummatory anhedonia.

Psychotic and autistic traits among magicians and their relationship with creative beliefs.

There is a common perception that creativity is associated with psychopathology. Previous studies have shown that members of creative groups such as comedians, artists and scientists scores higher than the norm on psychotic traits, and scientists in STEM (science, technology, engineering and mathematics) fields score highly on autistic traits. To test whether magicians, a creative group that has not been studied before, also score highly on psychopathological traits and autism, and to test the associations of creative self-efficacy and creative identity with schizotypal and autistic traits among magicians. A sample of 195 magicians and 233 people from the general population completed measures of schizotypal traits (Oxford-Liverpool Inventory of Feelings and Experiences) and autism (Abridged Version of the Autism-Spectrum Quotient), as well as the Short Scale of Creative Self. Magicians were also compared with other creative groups with respect to schizotypal traits, based on previously published data. Magicians scored lower than the general population sample on three of the four schizophrenia measures (cognitive disorganisation, introvertive anhedonia and impulsive nonconformity) but did not differ with respect to unusual experiences or autism scores. Magicians scored higher on creative self-efficacy and creative personal identity than the general sample. Magicians' scores on schizotypal traits were largely lower than those of other creative groups. Originality of magic was positively correlated with unusual experiences (r = 0.208), creative self-efficacy (r = 0.251) and creative identity (r = 0.362). This is the first study to show a creative group with lower scores than norms on psychotic traits. The results highlight the unique characteristics of magicians and the possible myriad associations between creativity and mental disorders among creative groups.

Psychological variables associated with resistance to treatment with serotonin and noradrenaline reuptake inhibitors in fibromyalgia

ObjectiveThe treatment of fibromyalgia (FM) often offers only partial pain relief. Among the most effective drugs for FM pain are serotonin and noradrenalin reuptake inhibitors (SNRI). Few studies investigated the affective temperaments and personality features in FM. Our objective was to explore the associations between the affective temperaments, personality traits, schizotypy and response to SNRI treatment in FM. Methods60 FM patients: 30 responsive to SNRI (FM T[+]), 30 non-responsive to SNRI (FM T[−] and 30 healthy controls were recruited. Resistance to SNRI was defined as <30% pain reduction during at least 8-week treatment. Subjects were assessed by physician and filled self-report questionnaires: Temperament Scale of Memphis, Pisa and San Diego- autoquestionnaire, Ten Item Personality Inventory, Oxford-Liverpool Inventory of Feelings and Experiences and Fibromyalgia Impact Questionnaire (FIQ). ANOVA analysis and simple logistic regressions were used to examine the links between psychological variables and lack of response to SNRI. ResultsFM T[−] presented higher scores in total FIQ and in physical, work, well-being, pain, fatigue/sleep, stiffness domains than FM T[+]. FM T[−] showed higher levels of: irritable and anxious temperaments, neuroticism, schizotypy than FM T[+]. The levels of depressive, irritable and anxious temperaments, introversion, neuroticism and schizotypy were linked to lack of response to SNRI. ConclusionsFM T[+] and FM T[−] differ in clinical presentation and psychological features. The levels of affective temperaments, personality and schizotypal traits are associated with lack response to SNRI in FM.

Validation of the Korean Version of the Community Assessment of Psychic Experiences in General Population.

The Community Assessment of Psychic Experiences has been widely translated and commonly used as a measure for psychotic experiences and psychosis proneness in clinical and research environments worldwide. This study aimed to establish the psychometric properties (reliability and validity) and factor structure of a Korean version of the Community Assessment of Psychic Experiences (K-CAPE) in the general population. A total of 1,467 healthy participants completed K-CAPE and other psychiatric symptom-related scales (Paranoia scale, Patient Health Questionnaire-9, Dissociative Experiences Scale-II, and Oxford-Liverpool Inventory of Feelings and Experiences) via online survey. K-CAPE's internal reliability was analyzed using Cronbach's alpha coefficient. Confirmatory factor analysis (CFA) was performed to investigate whether the original three-factor model (positive, negative, and depressive) and other hypothesized multidimensional models (including positive and negative subfactors) were suitable for our data. Exploratory factor analysis (EFA) was conducted to explore better alternative factor solutions with a follow-up CFA. To assess convergent and discriminant validity, we examined correlations between K-CAPE subscales with other established measures of psychiatric symptoms. K-CAPE showed good internal consistency in all original three subscales (all greater than α=0.827). The CFA demonstrated that the multidimensional models exhibited relatively better quality than the original three-dimensional model. Although the model fit indices did not reach their respective optimal thresholds, they were within an acceptable range. Results from the EFA indicated 3-5 factor solutions. In 3-factor solution, "negative-avolition" items were founded to be loaded more consistently with depressive items than with the negative dimension. In 4-factor solution, positive items were divided into two subfactors: "positive-bizarre experiences" and "positive-delusional thoughts," while negative symptoms were separated into two distinct subfactors in 5-factor solution: "negative-avolition (expressive)," and "negative-social (experiential)." The correlation coefficients between K-CAPE subscales and corresponding measurements were significant (p<0.001), confirming the convergent and discriminant validity. Our study provides evidence to support the reliability and validity of the K-CAPE and its use as a measure of psychotic symptoms in the Korean population. Although alternative factor structures did not improve the model fit, our EFA findings implicate the use of subfactors to investigate more specific domains of positive and negative symptoms. Given the heterogeneous nature of psychotic symptoms, this may be useful in capturing their different underlying mechanisms.

Trait schizotypy and the psychosis prodrome: Current standard assessment of extended psychosis spectrum phenotypes

Schizotypy has become an increasingly important construct for elaborating psychotic disorders that vary along the schizophrenic spectrum. However, different schizotypy inventories vary in conceptual approach and measurement. In addition, commonly used schizotypy scales have been seen as qualitatively different from screening instruments for prodromal schizophrenia like the Prodromal Questionnaire-16 (PQ-16). Our study investigated the psychometric properties of three schizotypy questionnaires (the Schizotypal Personality Questionnaire-Brief, Oxford-Liverpool Inventory of Feelings and Experiences, and the Multidimensional Schizotypy Scale) as well as the PQ-16 in a cohort of 383 non-clinical subjects. We initially evaluated their factor structure using Principal Component Analysis (PCA) and used Confirmatory Factor Analysis (CFA) to test a newly proposed composition of factors. PCA results support a three-factor structure of schizotypy that accounts for 71% of the total variance, but also shows cross-loadings of some schizotypy subscales. CFA of the newly composed schizotypy factors (together with an added neuroticism factor) shows good fit. Analyses including the PQ-16 indicate considerable overlap with measures of trait schizotypy, suggesting that the PQ-16 might not be quantitatively or qualitatively different from schizotypy measurements. Taken together, results indicate that there is good support for a three-factor structure of schizotypy but also that different schizotypy measurements grasp facets of schizotypy differently. This points towards the need for an integrative approach for assessing the construct of schizotypy.

Structural Relationships Among Mental Boundaries, Childhood Imaginary Companions, Creative Experiences, and Entity Encounters.

This study investigated relationships between thin mental boundary functioning, creativity, imaginary companions (ICs), and anomalous '(entity) encounter experiences.' A convenience sample of 389 respondents completed the Revised Transliminality Scale, Oxford-Liverpool Inventory of Feelings and Experiences, Creative Experiences Questionnaire, Survey of Strange Events, and a measure of Childhood Imaginary Companions. Competing testing with path analysis found that the best-fitting model was consistent with the causal chain of 'Thin Boundaries (transliminality and schizotypy) → Creative Experiences → ICs → (Entity) Encounter Experiences.' These results suggest that deep-types of ICs (i.e., showing apparent independent agency) are perhaps most accurately characterized as syncretic cognitions versus hallucination-like experiences. The authors examine these findings relative to study limitations, as well as discussing the need for future research that approaches ICs as a special mental state that can facilitate allied altered-anomalous experiences. In this context, this study furthered understanding of relationships between conscious states related to mental boundaries, childhood imaginary companions, creative experiences, and entity encounters.

Distinct neural signatures of schizotypy and psychopathy during visual word‐nonword recognition

Previous behavioural data indicate lower word‐nonword recognition accuracy in association with a high level of positive schizotypy, psychopathy, or motor impulsivity traits, each with some unique contribution, in the general population. This study aimed to examine the neural underpinnings of these associations using functional magnetic resonance imaging (fMRI) in a volunteer sample. Twenty‐two healthy English‐speaking adults completed self‐report measures of schizotypy (Oxford‐Liverpool Inventory of Feelings and Experiences [O‐LIFE]), psychopathy (Triarchic Psychopathy Measure [TriPM]), and impulsivity (Barratt Impulsiveness Scale [BIS‐11]) and underwent whole‐brain fMRI while performing a lexical decision task (LDT) featuring high and low‐frequency words, real nonwords, and pseudohomophones. Higher positive schizotypy (Unusual Experiences) was associated with lower cerebellum activity during identification of low‐frequency words (over real nonwords). Higher Boldness (fearless dominance) and Meanness (callous aggression) facets of psychopathy were associated with lower striatal and posterior cingulate activity when identifying nonwords over words. Higher Motor Impulsivity was associated with lower activity in the fusiform (bilaterally), inferior frontal (right‐sided), and temporal gyri (bilaterally) across all stimuli‐types over resting baseline. Positive schizotypy, psychopathy, and impulsivity traits influence word‐nonword recognition through distinct neurocognitive mechanisms. Positive schizotypy and psychopathy appear to influence LDT performance through brain areas that play only a supportive (cerebellum) or indirect role in reading‐related skills. The negative association between Motor Impulsivity and activations typically found for phonological processing and automatic word identification indicates a reduced bilateral integration of the meaning and sound of mental word representations, and inability to select the appropriate outputs, in impulsive individuals.

No influence of sex on the relationship between schizotypy factors and executive control across the schizophrenia spectrum

Sex differences in symptoms and executive control across schizophrenia spectrum disorders (SSD) are consistently reported. Similarly, these findings of sex differences are also observed in schizotypy, that is, schizophrenia-like features occurring in healthy individuals in the absence of a clinical diagnosis. This study aimed to examine the relationships between performance on three major domains of executive control: performance monitoring, response inhibition, and cognitive set-shifting, and schizotypy factor scores in both SSD patients and healthy controls (HCs), and whether sex moderated any relationships observed. A total of 111 (67 males and 44 females) patients with SSD and 258 (129 males and 129 females) HCs were included in this study. Schizotypal personality traits (in both SSD and HC) was assessed using the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE). Executive control performance was assessed using seven tasks. Stepwise linear regressions revealed that performance on cognitive set-shifting tasks was significantly associated with the introvertive anhedonia, cognitive disorganisation, and unusual experiences subscales of the O-LIFE. When sex was examined as a moderator, it was not a significant moderator of any of the relationships between cognitive set-shifting tasks and schizotypy factors. The results suggest that independent of sex, cognitive set-shifting ability is associated to an increased vulnerability to schizotypal personality traits, although performance monitoring and response inhibition did not.

Examining relationships between state and trait psychotic symptoms and quality of life in schizophrenia spectrum disorders

Positive and negative symptoms are core aspects of schizophrenia and have been shown to influence patient quality of life (QOL). Previous studies have largely focused on current or state symptoms, with limited work on the contributions of trait symptoms to QOL. This study sought to examine the relationship between both state and trait symptoms and objective and subjective QOL. Fifty-three schizophrenia spectrum disorder patients and 47 healthy controls were recruited. State symptomatology was assessed using the Positive and Negative Syndrome Scale in the patients only. In all participants, trait symptoms were assessed using the Oxford-Liverpool Inventory of Feelings and Experiences, and QOL using Lehman's QOL Interview. Hierarchical linear regression analyses, controlling for depression and neurocognition, revealed that negative state symptoms were related to objective QOL within the patients, while negative trait symptoms were associated with both objective and subjective QOL in patients and healthy controls. No relationships were observed with positive state or trait symptoms and either QOL measure. The findings suggest a degree of complexity in the associations between symptoms and QOL, with primacy for negative symptoms at both state and trait levels. A greater appreciation of trait symptoms may help explain non-complementary QOL changes following symptom remission.

Clarifying the roles of schizotypy and psychopathic traits in lexical decision performance

IntroductionSome studies suggest that lexical recognition is impaired in people with schizophrenia, psychopathy and/or antisocial personality disorders, but not affective disorders. We examined the extent to which various traits dimensionally linked to one or more of these disorders are associated with lexical recognition performance in the general population. MethodsSeventy-eight healthy English-speaking participants completed self-report measures of schizotypy, psychopathy, impulsivity, depression, anxiety and stress. All participants were assessed on a one-choice variant of a lexical decision task (LDT). ResultsMeanness and Boldness traits of psychopathy (Triarchic Psychopathy Measure), and positive schizotypy (Unusual Experiences, Oxford-Liverpool Inventory of Feelings and Experiences) were associated with poor word-nonword accuracy, and predicted a significant amount of unique variance (Meanness, 12%; Boldness, 4.8%; Positive Schizotypy, 4.4%; total 21%) in performance. Higher motor impulsivity predicted 30% of the variance in low-frequency words recognition accuracy, but only in non-native English speakers. Affective traits were not associated with LDT performance. ConclusionPsychopathic traits show stronger negative associations with lexical recognition performance than schizotypal traits, and impulsivity may differently influence lexical decision performance in native and non-native speakers. Further studies are needed to replicate these findings, especially the influence of language familiarity in the impulsivity-performance relationship, and to clarify the influence of corresponding symptom dimensions in lexical recognition abilities, taking language familiarity, migration status, and comorbidity into account, in people with schizophrenia, psychopathy, and/or antisocial personality disorders.

Schizotypy in Parkinson\u2019s disease predicts dopamine-associated psychosis

Psychosis is the most common neuropsychiatric side-effect of dopaminergic therapy in Parkinson’s disease (PD). It is still unknown which factors determine individual proneness to psychotic symptoms. Schizotypy is a multifaceted personality trait related to psychosis-proneness and dopaminergic neurotransmission in healthy subjects. We investigated whether (1) PD patients exhibit lower schizotypy than controls and (2) dopamine-related neuropsychiatric side-effects can be predicted by higher schizotypy. In this cross-sectional study, we used the Oxford-Liverpool Inventory of Feelings and Experiences in 56 PD patients (12 women, mean ± sd age: 61 ± 11 years) receiving their usual dopaminergic medication and 32 age-matched healthy controls (n = 32; 18 women, mean ± sd age: 57 ± 6 years). We further compared schizotypy scores of patients with (n = 18, 32.1%) and without previously experienced psychosis. We found that patients exhibited lower schizotypy than controls. Further, patients with a history of psychosis exhibited higher schizotypy than patients without these symptoms. Using an information theoretic measure and a machine learning approach, we show that schizotypy yields the greatest predictive value for dopamine-associated hallucinations compared to other patient characteristics and disease related factors. Our results indicate an overlap between neural networks associated with schizotypy and the pathophysiology of PD and a relationship between schizotypy and psychotic side-effects of dopaminergic medication.

Semantic priming and schizotypal personality: reassessing the link between thought disorder and enhanced spreading of semantic activation.

The term schizotypy refers to a group of stable personality traits with attributes similar to symptoms of schizophrenia, usually classified in terms of positive, negative or cognitive disorganization symptoms. The observation of increased spreading of semantic activation in individuals with schizotypal traits has led to the hypothesis that thought disorder, one of the characteristics of cognitive disorganization, stems from semantic disturbances. Nevertheless, it is still not clear under which specific circumstances (i.e., automatic or controlled processing, direct or indirect semantic relation) schizotypy affects semantic priming or whether it does affect it at all. We conducted two semantic priming studies with volunteers varying in schizotypy, one with directly related prime-target pairs and another with indirectly related pairs. Our participants completed a lexical decision task with related and unrelated pairs presented at short (250 ms) and long (750 ms) stimulus onset asynchronies (SOAs). Then, they responded to the brief versions of the Schizotypal Personality Questionnaire and the Oxford-Liverpool Inventory of Feelings and Experiences, both of which include measures of cognitive disorganization. Bayesian mixed-effects models indicated expected effects of SOA and semantic relatedness, as well as an interaction between relatedness and directness (greater priming effects for directly related pairs). Even though our analyses demonstrated good sensitivity, we observed no influence of cognitive disorganization over semantic priming. Our study provides no compelling evidence that schizotypal symptoms, specifically those associated with the cognitive disorganization dimension, are rooted in an increased spreading of semantic activation in priming tasks.

T162. THICKER PREFRONTAL CORTEX IS ASSOCIATED WITH SUBCLINICAL NEGATIVE SYMPTOMS IN SCHIZOTYPY - AN ENIGMA CONSORTIUM META-ANALYSIS

BackgroundNegative symptoms can be seen to represent a continuum from subclinical manifestations in the general population to severe symptoms in schizophrenia. Neuroanatomical studies show evidence of fronto-striatal structural abnormalities linked to negative symptoms in patients with schizophrenia (Walton et al. 2018). However, it remains an open question whether these structural associations are also observed in ostensibly healthy individuals reporting subclinical negative symptoms. The present study used structural T1-weighted brain imaging data from the ENIGMA Schizotypy Working Group to investigate the relationship between subclinical negative symptoms and fronto-striatal structural measures.MethodsWe included 2,235 healthy unmedicated individuals with varying levels of schizotypy from 17 centers around the world. The complete sample had a weighted mean (range) age of 29.2 (15.9–39.6) and 59.4% (51–100) were male. Subclinical negative symptoms were assessed at each site separately using factor scores from self-report schizotypy questionnaires (i.e., the Community Assessment of Psychic Experiences, the Oxford-Liverpool Inventory of Feelings and Experiences, or the Schizotypal Personality Questionnaire). Based on prior studies in schizophrenia, we obtained cortical thickness from 22 frontal regions-of-interest (ROIs) and subcortical volumes from 6 striatal ROIs using FreeSurfer. We performed meta-analyses of effect sizes (standardized regression coefficients) from a model predicting mean cortical thickness by subclinical negative symptom scores, adjusting for age, sex, and site. The same analysis was repeated for subcortical volumes including intracranial volume as additional covariate.ResultsMeta-analyses revealed significant positive associations between subclinical negative symptoms and cortical thickness of the left frontal pole (βstd=0.091; pFDR=0.009), right medial orbitofrontal cortex (βstd=0.083; pFDR=0.009) and right anterior cingulate cortex (βstd=0.07; pFDR=0.011).DiscussionUsing a large sample of healthy unmedicated individuals with varying levels of schizotypal personality traits, this ENIGMA meta-analysis showed that subclinical negative symptoms are associated with thicker prefrontal cortex. The present data are contrary to previous findings in schizophrenia, which demonstrates a relationship between negative symptoms and lower prefrontal cortical thickness (Walton et al. 2018). These divergent neural correlates suggest that thicker cortex could be a potential compensatory mechanism preventing individuals with schizotypy from the clinical manifestation of severe negative symptoms. Alternatively, greater prefrontal cortical thickness could also be associated with pathological processes along the negative symptom continuum prior to clinical manifestation.

Schizotypy and Risk-Taking Behaviour: the Contribution of Urgency

The Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) defines schizotypy as a multidimensional psychopathology construct comprising Unusual Experiences, Cognitive Disorganisation, Impulsive Nonconformity, and Introvertive Anhedonia. Previous research indicates that schizotypy is associated with various risky behaviours. Urgency (emotional impulsivity) has a unique and clinically important effect on risk-taking. However, the interplay between schizotypy and urgency in relation to risk-taking has not received adequate consideration. A sample of 204 participants completed self-report scales measuring Schizotypy, Urgency and Risk-taking behaviour. Using structural equation modelling, a mediational model tested the degree to which O-LIFE subfactors directly and indirectly (via urgency) predicted self-reported likelihood to engage in Risk-taking behaviour. Results indicated that Cognitive Disorganisation and Introvertive Anhedonia negatively predicted engagement in Risk-taking behaviour, whereas Impulsive Nonconformity positively predicted engagement in Risk-taking behaviour. Unusual Experiences, Cognitive Disorganisation and Impulsive Nonconformity had indirect effects on Risk-taking through Urgency. Inclusion of Urgency added explanatory power to the schizotypy-risk relationship.

Multi-echo fMRI, resting-state connectivity, and high psychometric schizotypy.

Disrupted striatal functional connectivity is proposed to play a critical role in the development of psychotic symptoms. Previous resting-state functional magnetic resonance imaging (rs-fMRI) studies typically reported disrupted striatal connectivity in patients with psychosis and in individuals at clinical and genetic high risk of the disorder relative to healthy controls. This has not been widely studied in healthy individuals with subclinical psychotic-like experiences (schizotypy). Here we applied the emerging technology of multi-echo rs-fMRI to examine corticostriatal connectivity in this group, which is thought to drastically maximize physiological noise removal and increase BOLD contrast-to-noise ratio. Multi-echo rs-fMRI data (echo times, 12, 28, 44, 60 ms) were acquired from healthy individuals with low (LS, n = 20) and high (HS, n = 19) positive schizotypy as determined with the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE). After preprocessing to ensure optimal contrast and removal of non-BOLD signal components, whole-brain functional connectivity from six striatal seeds was compared between the HS and LS groups. Effects were considered significant at cluster-level p < .05 family-wise error correction. Compared to LS, HS subjects showed lower rs-fMRI connectivity between ventromedial prefrontal regions and ventral striatal regions. Lower connectivity was also observed between the dorsal putamen and the hippocampus, occipital regions, as well as the cerebellum. These results demonstrate that subclinical positive psychotic-like experiences in healthy individuals are associated with striatal hypoconnectivity as detected using multi-echo rs-fMRI. Further application of this approach may aid in characterizing functional connectivity abnormalities across the extended psychosis phenotype.

Odd and disorganized–Comparing the factor structure of the three major schizotypy inventories

Schizotypy is a personality-framework currently considered a comprehensive and useful construct in schizophrenia research and becoming ever more accepted within psychiatry. Thus, it is crucial to obtain a unifying and generally accepted means of its measuring. The three most commonly used psychometric schizotypy inventories, the Wisconsin Schizotypy Scales, Schizotypal Personality Questionnaire and Oxford-Liverpool Inventory of Feelings and Experiences were, however, built upon different theoretical schizotypy models, wherefore comparing results from studies that have used different inventories is difficult and sometimes questionable. Therefore, an analysis of all three inventories was conducted within the same sample of 327 healthy participants to illustrate the similarities and differences in factor structures. Results showed that findings are likely dependent on the used assessment instrument. A following item-level factor analysis was conducted to investigate the shared structure of all three inventories, in order to illustrate a framework interpretable as “common ground” between measures. This adjusted four-factor structure may be used to better aid comparisons between schizotypy-studies having used different inventories. At least, our findings illustrate the necessity of viewing individual results before the background of the theoretical framework of the respective measurement tool.

Do schizotypy dimensions reflect the symptoms of schizophrenia?

The personality characteristics and symptoms observed in schizophrenia are postulated to lie on a continuum, with non-clinical manifestations referred to as schizotypy. High schizotypy behaviours are argued to correspond with the three main clusters of symptoms in schizophrenia: positive, negative and cognitive/disorganised symptoms, yet there is limited empirical evidence to support this. This study aimed to investigate whether schizotypy dimensions significantly correlate with their respective schizophrenia symptomatology in the largest sample to date. A total of 361 adults (103 patients with schizophrenia/schizoaffective disorder and 258 healthy controls) were assessed for schizotypy using the Oxford-Liverpool Inventory of Feelings and Experiences. The MATRICS Consensus Cognitive Battery supplemented by the Stroop task and Wisconsin Card Sorting Test was administered to all participants to obtain objective measurements of cognition. Schizophrenia symptomatology was assessed using the Positive and Negative Syndrome Scale in patients only. The results demonstrated significant correlations between the Oxford-Liverpool Inventory of Feelings and Experiences positive and negative subscales and their respective Positive and Negative Syndrome Scale subscales only, indicating that positive and negative schizotypy dimensions across patients and controls accurately reflect the respective schizophrenia symptomatology observed in patients. Cognitive performance did not correlate with cognitive/disorganised symptom dimensions of the Oxford-Liverpool Inventory of Feelings and Experiences or the Positive and Negative Syndrome Scale, indicating that cognitive impairment is an independent symptom dimension that requires objective cognitive testing. Collectively, the findings provide empirical evidence for the continuum theory and support the use of schizotypy as a model for investigating schizophrenia.

T18. MULTIVARIATE BRAIN ANATOMICAL DIFFERENCES IN POSITIVE AND NEGATIVE SCHIZOTYPY: PRELIMINARY RESULTS FROM THE TYPIA STUDY

BackgroundIn schizotypy, a factor structure similar to the one observed in schizophrenia has been unraveled, being the positive and negative the most consistently replicated dimensions. Despite this fact, most of the studies on brain volume patterns in schizotypy consider it as an unitary rather than a multidimensional construct. Hence, based on previous results showing that schizophrenia and schizotypal personality traits share common neurodevelopmental patterns, it is hypothesized that brain volumetric patterns in individuals with high positive schizotypy are intrinsically different to those observed in persons reporting high negative schizotypy and to individuals with overall low schizotypal traits. The present study aims to evaluate this hypothesis using novel machine learning techniques to address the multivariate nature of psychotic diseases and the brain itself.MethodsData from the TYPIA Study, an ongoing project conducted at the Ludwig-Maximilian University of Munich and the University of Bonn in Germany, was used to investigate whether brain volumetric patterns are distinct in healthy individuals with high positive (HPS) and high negative schizotypy (HNS) when compared to one another (HPS vs HNS) and to individuals with self-reported low schizotypy (LS vs HNS and LS vs HPS). A preliminary analysis on grey matter volumetric patterns from 29 LS (19 f., mean age: 24.6 y.), 28 HNS (20 f., mean age: 26.8 y.) and 23 HPS (17 f., mean age: 26.4 years) individuals from the general population without any current psychiatric diagnosis was performed. Group divisions were based on the introvertive anhedonia and unusual experiences subscales from the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE). Structural images were preprocessed with a standard voxel based morphometry pipeline using the SPM-based CAT12 toolbox in Matlab. After age, sex and grey matter intracranial volume and center corrections, a linear support vector classification (SVC) algorithm was used to assess separability between the groups.ResultsOur preliminary cross-validated results showed that LS and HNS can be separated with 56.0 % balanced accuracy (BAC), whereas LS vs HPS and HNS vs HPS allowed for only 42.87% and 48.8% BAC respectively. Interestingly, a post-hoc analysis comparing LS vs both high schizotypy groups merged together showed the highest BAC (59.2%). As expected, the brain differences between groups are rather small, since the sample consists fully of healthy controls. However, these results indicate that personality traits related to HNS are linked to more pronounced changes in the brain as compared to HPS. Nevertheless, schizotypy as a combination of the positive and negative dimensions allowed for a higher classification accuracy when compared to LS, supporting the notion of schizotypy as a unitary construct as observed from the post-hoc analysis. Furthermore, HNS and HPS were not separable by the algorithm, most likely due to the intrinsic heterogeneity of the construct.DiscussionOur results align with previous studies claiming that negative symptoms are associated with structural changes in the CNS whereas positive symptoms relate to changes in functioning and activation of the brain. A larger sample as well as using other data modalities will confirm the stability of our findings. Research on volumetric patterns of the brain areas related to negative symptoms in non-clinical samples might lead to a better understanding of the underlying causes of schizophrenia. Above all, our results show that investigating non-clinical expression of psychosis-like symptoms is a promising strategy to understand the prodromal stadium of schizophrenia.

T61. ANTISACCADE AND MEMORY GUIDED SACCADE PERFORMANCE ACROSS THE SCHIZOPHRENIA CONTINUUM

BackgroundSaccadic (ocular motor) deficits are one of the most replicated findings in schizophrenia. However, less research has been conducted investigating the broader schizophrenia continuum. Recent research suggests that the personality characteristics and symptoms observed in schizophrenia lie on a continuum with subclinical symptoms, known as schizotypy, observed in the non-clinical population. Schizotypy is considered a suitable model for investigating schizophrenia as it mirrors the symptoms, albeit in a more subtle manner. As saccadic deficits are a cognitive hallmark of schizophrenia, it is believed that saccadic deficit may be associated with higher schizotypy. The aim of the current study was to 1) replicate previous findings of impairments in antisaccade and memory-guided saccade performance in schizophrenia and 2) investigate the relationship between antisaccade and memory-guided saccade performance and schizotypy.Methods105 adults (35 patients with schizophrenia/schizoaffective disorder and 70 healthy controls) completed the antisaccade and memory-guided saccade tasks, which engage spatial working memory and inhibition processes. The variables analysed for both saccade paradigms were error rate, latency (ie. reaction time) and gain (ie. spatial accuracy). Schizotypy was assessed using the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE), a 104 item questionnaire which measures the three main schizotypy factors: Unusual Experiences, Introvertive Anhedonia and Cognitive Disorganisation. A total O-LIFE score was also calculated from these three schizotypy factors as a representation of global schizotypy. Controls were then divided into low (n = 35) and high schizotypy groups (n = 35). A MANOVA was conducted to observe differences in eye movement variables between low schizotypy individuals, high schizotypy individuals and patients. Correlations were also conducted to further investigate these relationships.ResultsAntisaccade error rate, (p < 0.001), antisaccade latency (p = 0.007), memory-guided saccade error rate (p = 0.009) and latency (p < 0.001) were significantly different between patients and controls. When comparing low schizotypy, high schizotypy and patient groups, the MANOVA revealed significant differences for antisaccade and memory-guided saccade latency and a non-significant trend for antisaccade gain. However, post-hoc analyses revealed that there was only a significant difference between low schizotypy and patient groups (p < 0.001), but not between low schizotypy and high schizotypy nor between high schizotypy and patient. Looking across the schizophrenia continuum, there were significant correlations between the total O-LIFE score and antisaccade gain (p = 0.033), memory-guided saccade latency (p = 0.014) and memory-guided saccade gain (p = 0.011). A non-significant trend was also observed between the total O-LIFE score and antisaccade latency (p = 0.088).DiscussionThis study replicated previous findings of impaired saccade performance in schizophrenia. In addition, it also replicated findings of impaired antisaccade performance in higher schizotypy and is the first study to investigate and demonstrate the relationship between higher schizotypy and impaired memory-guided saccade performance. Overall, these findings supporting the use of schizotypy as a model for schizophrenia and also support the theory of schizotypy and a broader schizophrenia continuum.

T63. TOWARDS A COMPREHENSIVE SEMANTIC MEMORY NETWORK IN SCHIZOPHRENIA: PRELIMINARY RESULTS USING MAGNETOENCEPHALOGRAPHY (MEG) IN SCHIZOTYPY

BackgroundSemantic memory (memory for facts, concepts, and knowledge of the external world) abnormalities are predicted to underlie disturbances in thought and language, deficits in cognitive domains, and the development and maintenance of delusions in patients with schizophrenia. Electroencephalographic (EEG) recordings have successfully identified the neural time course for the processing of semantic information as an electrophysiological response between 300 and 500ms post stimulus (i.e., the N400). The N400 is a remarkably consistent and highly sensitive neural response to semantic relationships, and is thought to index the binding of current stimuli into context by detecting whether meaning is shared with recently processed stimuli or items in memory. To date, the N400 appears to be amodal: an index of semantic processing irrespective of stimulus type (e.g., word/picture stimuli alike), and has shown mixed findings in schizophrenia. However, existing literature has largely relied on EEG or functional magnetic resonance imaging (fMRI) techniques, and these are constrained in spatial and temporal resolution, respectively. Comparatively, MEG provides excellent spatio-temporal resolution, not possible from other stand-alone neuroimaging techniques. We aimed to determine the neuromagnetic correlates of novel semantic triads in both lexical and picture form, and to determine N400m differences in high/low schizotypal samples.MethodsMEG was recorded (whole-head 306 channel Elekta Neuromag® TRIUX magnetometer system) in 35 nonclinical controls (18 male) while completing a novel explicit semantic association task. MEG data were continuously sampled at 1KHz (0.1Hz high pass filter). Following MaxFiltering, data was processed using MNE for Python. Data were filtered offline (40Hz lowpass) and epoched at -300ms to 800ms post- target stimulus onset. The largest peak was measured at sensor triplets at temporo-parietal sites in both hemispheres. High/low schizotypal samples were determined by a median split of the Oxford-Liverpool Inventory of Feelings and Experiences (cognitive disorganisation scale; high=17, low=18).ResultsPreliminary sensor level analyses demonstrated an N400m at temporo-parietal sites in response to both word and picture stimulus sets (with an earlier peak to pictures). Neither amplitude nor latency was significantly different between schizotypal samples, however a significant task x hemisphere x group interaction was found for N400m latency, F(1.00,33.00) = 6.18, p<.02.DiscussionAn N400m was confirmed in response to the novel lexical task. The earlier peak (~200ms) to picture stimuli suggests that pictorial semantic information may be processed more rapidly than lexical information. The significant schizotypal group latency interaction demonstrated that while individuals low in schizotypal traits process lexical stimuli first in the right hemisphere (followed by the left) and picture stimuli first in the left hemisphere (followed by the right), individuals high in schizotypal traits do not demonstrate hemispheric specificity/laterality according to stimulus type. The data is currently being analysed for (i) source localisation, (ii) deep source contributions (e.g., hippocampus), and (iii) de/synchronisation of neural oscillations (across six frequency bands; 1-8Hz, 8-30Hz, 30-50Hz, 70-120Hz, 120-200Hz, and 200-300Hz).