Higher Schizotypal Personality Questionnaire Research Articles

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

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

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

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

Is there a common vulnerability in cannabis phenomenology and schizotypy? The role of the N170 ERP

Cannabis use is a known risk factor for the development of psychosis, although the precise nature of this relationship is unclear. The phenomenological experiences associated with cannabis use vary dramatically, and for some resemble certain features of psychosis. We hypothesized that individuals who report particularly unusual experiences associated with cannabis use would demonstrate similar electrophysiological patterns to those who score high on schizotypal personality traits. The Cannabis Experiences Questionnaire (CEQ) and the Schizotypal Personality Questionnaire (SPQ) were used to measure these experiences and traits. A sample of 97 individuals were placed into one of three experimental or two control groups based on their questionnaire scores. These were the “High CEQ”, “High SPQ”, “High on Both”, “Average Users” and “Control” (non-using) groups. Participants completed a visual face perception task. Electroencephalography was used to measure the neural response to the stimuli. The N170 event-related potential (ERP) was used to measure perceptual encoding of the stimulus. The experimental groups elicited significantly reduced N170 ERPs compared to the Control group. The Average User group did not significantly differ from the Control group, and approached significance with the High SPQ group. None of the high scoring groups significantly differed in N170 ERP response from each other. Replicating past research, the CEQ and SPQ scales moderately correlated with each other. The attenuated N170 ERP demonstrated by the high scoring experimental groups may reflect a manifestation of an underlying shared vulnerability.

L-dopa modulates striatal functional connectivity in adults with psychotic-like experiences: A randomized double-blind placebo-controlled study

IntroductionAccording to the dopamine hypothesis functional brain abnormalities and neurochemical alterations may converge to cause psychosis through aberrant salience attribution. Indeed, resting-state functional magnetic resonance imaging (rs-fMRI) has revealed widespread brain disconnectivity across the psychotic spectrum.ObjectivesTo advance the understanding of the dopaminergic involvement in intrinsic functional connectivity (iFC) and its putative relationship to the development of psychotic disorders we aimed to investigate the link between L-Dopa, a dopamine precursor, and its modulation of striatal iFC in subthreshold psychosis, i.e. non-clinical psychosis.MethodsWe used a randomized, double-blind placebo controlled study design including in our sample 56 healthy, male, right-handed, subjects with no familiar risk factors for psychosis who were assessed with the Schizotypal Personality Questionnaire (SPQ) and underwent 10 minutes of rs-fMRI scanning. All subjects received either 250 mg of Madopar DR®(200 mg L-Dopa plus 50 mg benserazid, dual release form) or a placebo. We analysed resting-state iFC of 6 striatal seeds, known to evoke dopamine related networks.ResultsThe main effect of L-Dopa presented itself (FWE-corrected) as a significant decrease in iFC from the right ventral striatum to the cerebellum and the precuneus cortex, and an increase in iFC to the occipital cortex. Subjects with high SPQ positive symptom sub-scores showed a significant increase of L-Dopa induced connectivity.ConclusionWe identified striatal functional connectivity being modulated by augmented dopamine availability, and in support of the dopamine hypothesis, we found that those iFC patterns are associated to high scores of psychotic like experiences.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Impaired context processing during irony comprehension in schizotypy: An ERPs study

Mentalizing deficits are a core manifestation of schizophrenia spectrum disorders. They contribute to the social handicap associated with the pathology, leading to disruption in autonomy, professional achievement, and interpersonal relationships. However, the underlying mechanisms of these deficits remain poorly understood. The aim of the present study was to test the hypothesis that context processing deficits would be responsible for mentalizing difficulties in schizotypy (personality traits considered as attenuated manifestations of schizophrenic symptoms) by using an irony comprehension task. Irony processing is a mentalizing exercise that requires the ability to take into account the semantic context to understand the literal meaning of the utterance, and to integrate the pragmatic context to infer the speaker's intention. These two steps of processing can be indexed by the N400 and P600 components, respectively, of event-related brain potentials (ERPs). Forty participants were assigned to high or low schizotypy groups according to their Schizotypal Personality Questionnaire (SPQ) score, and ERPs were recorded while they read short stories ending with a literal, ironic, or incompatible statement. In the low-SPQ group, there was a significant N400 semantic context effect (literal targets elicited less negative N400 amplitudes compared to incompatible targets) followed by a P600 pragmatic context effect (ironic targets evoked greater positive P600 amplitudes than literal targets). In contrast, there was neither a N400 nor P600 effect in the high-SPQ group. These abnormalities were associated with high interpersonal SPQ factor scores. These results show a strong association between context processing, mentalizing abilities, and interpersonal functioning in schizophrenia spectrum.

Assessment of self-disorders in a non-clinical population: Reliability and association with schizotypy

This study explores whether self-disorders occur and can be assessed reliably in a non-clinical sample, and whether the prevalence of these anomalies depends upon the degree of psychometrically defined schizotypy. Participants with either high (n=30) or low (n=20) schizotypy scores were interviewed using a modified version of the Examination of Anomalous Self-Experience (EASE). The degree to which interviewees experienced self-disorder symptoms was rated by the interviewer and an independent rater. Inter-rater reliability was calculated for each item, domain scores and the total score. For the total, sample most items (=66) showed substantial or perfect agreement (κ>0.61), with a few (=6) showing moderate agreement (κ>0.41). Reliability scores were only slightly lower when just the more homogeneous group of individuals with high Schizotypal Personality Questionnaire (SPQ) scores were examined. As expected, high SPQ scores were associated with a high level of self-disorders. In sum, the results suggest that self-disorders can be measured reliably in non-clinical samples and are particularly frequent in individuals with pronounced schizotypical traits.

Mismatch Field Provides a Biological Link Between High Autistic and Schizotypal Tendencies.

Event Abstract Back to Event Mismatch Field Provides a Biological Link Between High Autistic and Schizotypal Tendencies. Talitha Ford1* and David Crewther1* 1 Swinburne University of Technology, Australia The autism and schizophrenia spectra are well established as characteristic phenotypes existing on a continuum from pathology to personality traits. As evidence broadens, research shows striking interpersonal and social cognitive dysfunction similarities between the spectra, highlighting the need for biological markers. Mismatch Negativity/Field (MMN/F) quantifies pre-attentive processing, with temporal change detection deficits indexing various social, cognitive and functional abnormalities. We investigate the relationship between duration MMF and specific autistic and schizotypal tendency phenotypes. From a pool of 176 respondents to an online Autism Spectrum Quotient (AQ) and Schizotypal Personality Questionnaire (SPQ), aged 18 to 40, 28 participants: nine Control (m/f=5/4), seven High AQ (HA) (m/f=4/3), five High SPQ (HS)(m/f=5/0), and six High AQ/SPQ (HAS)) (m/f=4/2) were recruited for the MEG MMF scan. Correlations between MMF (long and short duration), and AQ and SPQ (total and subscale scores) were obtained. Furthermore, subsequent correlations were obtained between MMF and the two component scores revealed in the AQ and SPQ subscale Principal Components Analysis (PCA). Over the right auditory cortex, the long deviant MMF was significantly correlated with AQ total (-.51) and subscales Social Skills (-.42), Communication (-.42), Attention to Detail (-.38) and Imagination (-.47), SPQ total (-.51) and subscales Ideas of Reference (-.5), Suspiciousness (-.39), Social Anxiety (-.58) and No Close Friends (-.47), and PCA Component 1 (Interpersonal-Communication) (-.48) and Component 2 (Perceptual-Disorganisation) (-.42). The short duration MMF was significantly correlated with Communication (-.41) and Imagination (-.48). We conclude that temporal change detection abnormalities, particularly increased length, index social cognitive dysfunction, and thus highlight a potential biomarker for the phenotypic link between autism and schizophrenia spectrum disorders. Keywords: MEG, social cognition, social perception, autistic tendency, Mismatch Field, Schizotypal Tendency Conference: XII International Conference on Cognitive Neuroscience (ICON-XII), Brisbane, Queensland, Australia, 27 Jul - 31 Jul, 2014. Presentation Type: Poster Topic: Emotional and Social Processes Citation: Ford T and Crewther D (2015). Mismatch Field Provides a Biological Link Between High Autistic and Schizotypal Tendencies.. Conference Abstract: XII International Conference on Cognitive Neuroscience (ICON-XII). doi: 10.3389/conf.fnhum.2015.217.00175 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 19 Feb 2015; Published Online: 24 Apr 2015. * Correspondence: Miss. Talitha Ford, Swinburne University of Technology, Melbourne, Australia, talitha.ford@deakin.edu.au Prof. David Crewther, Swinburne University of Technology, Melbourne, Australia, dcrewther@swin.edu.au Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Talitha Ford David Crewther Google Talitha Ford David Crewther Google Scholar Talitha Ford David Crewther PubMed Talitha Ford David Crewther Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

BDNF val66met genotype and schizotypal personality traits interact to influence probabilistic association learning

The brain derived neurotrophic factor (BDNF) val66met polymorphism rs6265 influences learning and may represent a risk factor for schizophrenia. Healthy people with high schizotypal personality traits display cognitive deficits that are similar to but not as severe as those observed in schizophrenia and they can be studied without confounds of antipsychotics or chronic illness. How genetic variation in BDNF may impact learning in individuals falling along the schizophrenia spectrum is unknown. We predicted that schizotypal personality traits would influence learning and that schizotypal personality-based differences in learning would vary depending on the BDNF val66met genotype. Eighty-nine healthy adults completed the Schizotypal Personality Questionnaire (SPQ) and a probabilistic association learning test. Blood samples were genotyped for the BDNF val66met polymorphism. An ANOVA was performed with BDNF genotype (val homozygotes and met-carriers) and SPQ score (high/low) as grouping variables and probabilistic association learning as the dependent variable. Participants with low SPQ scores (fewer schizotypal personality traits) showed significantly better learning than those with high SPQ scores. BDNF met-carriers displaying few schizotypal personality traits performed best, whereas BDNF met-carriers displaying high schizotypal personality traits performed worst. Thus, the BDNF val66met polymorphism appears to influence probabilistic association learning differently depending on the extent of schizotypal personality traits displayed.

Migration Status, Familial Risk for Mental Disorder, and Schizotypal Personality Traits

Markedly raised incidence rates of schizophrenia and other psychotic disorders have been observed in several migrant and ethnic minority groups. To contribute to a better understanding of the elevated risk for psychotic disorders that is conferred by migration status, the present study examined effects associated with migration risk status on schizotypal personality traits, which are thought to reflect an underlying vulnerability to psychotic disorder. Effects of migration status were also compared to effects associated with a family history of psychopathology, which represents a robust nonspecific risk factor. We assessed schizotypal traits, using the Schizotypal Personality Questionnaire (SPQ), in a community-based sample of 62 Moroccan migrants and 41 Dutch nonmigrants, who were classified by the presence or absence of a family history of psychopathology. Overall, Moroccan migrants obtained higher SPQ scores than Dutch nonmigrants. However, migrants who had been classified as having a familial load of psychopathology displayed higher SPQ scores than migrants without such a family history, who in turn did not differ from Dutch nonmigrants. Furthermore, migrants with a familial load, relative to migrants without such a family history, reported higher levels of substance use and feelings of anxiety or depression, and perceived more often ethnic discrimination, which closely paralleled their SPQ scores. These findings indicate that primarily those migrants who are both intrinsically vulnerable and chronically exposed to social adversity, particularly ethnic discrimination, are at elevated risk for psychotic and other disorders. The results add to the evidence that migration status and perceived discrimination are associated with mental health.

An event‐related potential study of predictive and integrative semantic context processing in subjects with schizotypal traits

Context processing abnormalities may explain thought disorder in schizophrenia/schizotypy. This study aimed to assess predictive and integrative context processing in subjects with high or low scores on the Schizotypal Personality Questionnaire (SPQ). The N400 amplitude was recorded during semantic judgment of sentence pairs ending with a lateralized expected or unexpected word from the same or a different category (related and unrelated violation). In both groups, the N400 amplitude was less negative for expected words versus unrelated violations, regardless of which hemisphere received the stimulus, and for related versus unrelated violations, but only for left-hemisphere stimuli. The N400 amplitude for unrelated violations was less negative in subjects with high SPQ scores for both hemispheres. These results indicate that subjects with schizotypal traits use context to predict or integrate congruent words, but fail to inhibit incongruent words.

Poster #161 THE CHARACTERISTICS OF REVERSAL RESPONSE INITIATION AND ASSOCIATIVE LEARNING OF REWARD APPROACH AND LOSS AVERSION IN SCHIZOPHRENIA

Mentalizing deficits are a core manifestation of schizophrenia spectrum disorders. They contribute to the social handicap associated with the pathology, leading to disruption in autonomy, professional achievement, and interpersonal relationships. However, the underlying mechanisms of these deficits remain poorly understood. The aim of the present study was to test the hypothesis that context processing deficits would be responsible for mentalizing difficulties in schizotypy (personality traits considered as attenuated manifestations of schizophrenic symptoms) by using an irony comprehension task. Irony processing is a mentalizing exercise that requires the ability to take into account the semantic context to understand the literal meaning of the utterance, and to integrate the pragmatic context to infer the speaker's intention. These two steps of processing can be indexed by the N400 and P600 components, respectively, of event-related brain potentials (ERPs). Forty participants were assigned to high or low schizotypy groups according to their Schizotypal Personality Questionnaire (SPQ) score, and ERPs were recorded while they read short stories ending with a literal, ironic, or incompatible statement. In the low-SPQ group, there was a significant N400 semantic context effect (literal targets elicited less negative N400 amplitudes compared to incompatible targets) followed by a P600 pragmatic context effect (ironic targets evoked greater positive P600 amplitudes than literal targets). In contrast, there was neither a N400 nor P600 effect in the high-SPQ group. These abnormalities were associated with high interpersonal SPQ factor scores. These results show a strong association between context processing, mentalizing abilities, and interpersonal functioning in schizophrenia spectrum.

Pre-attentive Processing as the Link Between Schizotypy and Autistic Tendencies

Event Abstract Back to Event Pre-attentive Processing as the Link Between Schizotypy and Autistic Tendencies Talitha Ford1* 1 Swinburne University of Technology, Australia With the divergence of the term “childhood schizophrenia” in the late 1970’s the autism spectrum has been defined as an exclusive disorder. However, correlational studies exploring schizotypal and autistic tendencies expose links in cognitive and social functioning with similar neural deficits also revealed in both clinical and non-clinical groups. This study compares pre-attentive functioning in high scores on the Autistic Spectrum Quotient (AQ) and Schizotypal Personality Questionnaire (SPQ) using prepulse negativity (PPI) and mismatch field (MMF) with Magnetoencephalography (MEG) technology. Method: From 104 respondents a correlational analysis of typal subscales was conducted. PPI and MMF function was then assessed between six high AQ (HA), four high SPQ (HS), six high AQ/SPQ (HAS) and 8 controls. PPI consisted of 115dB startle stimuli preceded by 85dB prepulse over a 70dB white noise background. MMF consisted of duration (50ms and 200ms) and frequency (667hz and 1500hz) deviants among continuous standards (100ms, 1000hZ). Results: Strong significant typal correlations between the AQ and SPQ are revealed. Preliminary MMF analysis has revealed noticeable differences in mean global averages over temporal site for the standard and each deviant with HS greater than control, which in turn is greater than HA and HAS. Further analysis is underway to decipher these trends and obtain significance, in addition to PPI analysis. Conclusion: Evidence suggests that even at a typal level, abnormalities are identified in neural pre-attentive functioning which may manifest in cognitive and social function. Figure 1 Figure 2 Figure 3 Acknowledgements David Crewther Peter Goodin Rachel Batty Keywords: schizotypal traits, autistic traits, MMN (Mismatch negativity), prepulse inhibition, Magnetoencephalography Conference: ACNS-2012 Australasian Cognitive Neuroscience Conference, Brisbane, Australia, 29 Nov - 2 Dec, 2012. Presentation Type: Poster Presentation Topic: Sensation and Perception Citation: Ford T (2012). Pre-attentive Processing as the Link Between Schizotypy and Autistic Tendencies. Conference Abstract: ACNS-2012 Australasian Cognitive Neuroscience Conference. doi: 10.3389/conf.fnhum.2012.208.00036 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 14 Oct 2012; Published Online: 07 Nov 2012. * Correspondence: Miss. Talitha Ford, Swinburne University of Technology, Melbourne, Australia, talitha.ford@deakin.edu.au Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract Supplemental Data The Authors in Frontiers Talitha Ford Google Talitha Ford Google Scholar Talitha Ford PubMed Talitha Ford Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Schizotypal Traits in Healthy Women Predict Prefrontal Activation Patterns during a Verbal Fluency Task: A Near-Infrared Spectroscopy Study

Background/Aims: Previous functional neuroimaging studies have reported that patients with schizophrenia show reduced prefrontal activation during cognitive tasks whereas patients with schizotypal personality disorder (SPD) show preserved or even increased right prefrontal activation, compared to healthy controls; on the other hand, reduced hemispheric laterality is considered to be common to these two disorders. The aim of this study was to examine the possible association between schizotypal traits at a nonclinical level and prefrontal activation patterns during a letter version of the verbal fluency task (VFT). Methods: We examined the relationships of schizotypal traits as measured by the Schizotypal Personality Questionnaire (SPQ) in a nonclinical female population with prefrontal activation patterns during the VFT, using near-infrared spectroscopy. Twenty-seven healthy participants were divided into high (n = 14) and low (n = 13) SPQ groups by the median split of the total SPQ score. Results: Compared to the low SPQ group, the high SPQ group showed significantly larger right prefrontal activation during the performance of the VFT, leading to more bilateral activation. Conclusion: Our results suggest that schizotypal traits at a nonclinical level may be related to relative right prefrontal laterality with overall prefrontal activation being preserved, consistent with previous findings obtained by studies of patients with SPD.