Personality traits in schizophrenia and related personality disorders

Characterizing the Relationship between Personality Dimensions and Psychosis-Specific Clinical Characteristics

Background

Past studies associating personality with psychosis have been limited by small nonclinical samples and a focus on general symptom burden. This study uses a large clinical sample to examine personality's relationship with psychosis-specific features and compare personality dimensions across clinically and neurobiologically defined categories of psychoses.

Methods

A total of 1352 participants with schizophrenia, schizoaffective disorder, and bipolar with psychosis, as well as 623 healthy controls (HC), drawn from the Bipolar-Schizophrenia Network for Intermediate Phenotypes (BSNIP-2) study, were included. Three biomarker-derived biotypes were used to separately categorize the probands. Mean personality factors (openness, conscientiousness, extraversion, agreeableness, and neuroticism) were compared between HC and proband subgroups using independent sample t-tests. A robust linear regression was utilized to determine personality differences across biotypes and diagnostic subgroups. Associations between personality factors and cognition were determined through Pearson's correlation. A canonical correlation was run between the personality factors and general functioning, positive symptoms, and negative symptoms to delineate the relationship between personality and clinical outcomes of psychosis.

Results

There were significant personality differences between the proband and HC groups across all five personality factors. Overall, the probands had higher neuroticism and lower extraversion, agreeableness, conscientiousness, and openness. Openness showed the greatest difference across the diagnostic subgroups and biotypes, and greatest correlation with cognition. Openness, agreeableness, and extraversion had the strongest associations with symptom severity.

Conclusions

Individuals with psychosis have different personality profiles compared to HC. In particular, openness may be relevant in distinguishing psychosis-specific phenotypes and experiences, and associated with biological underpinnings of psychosis, including cognition. Further studies should identify potential causal factors and mediators of this relationship.

The genetics of niche-specific behavioral tendencies in an adaptive radiation of cichlid fishes

Behavior is critical for animal survival and reproduction, and possibly for diversification and evolutionary radiation. However, the genetics behind adaptive variation in behavior are poorly understood. In this work, we examined a fundamental and widespread behavioral trait, exploratory behavior, in one of the largest adaptive radiations on Earth, the cichlid fishes of Lake Tanganyika. By integrating quantitative behavioral data from 57 cichlid species (702 wild-caught individuals) with high-resolution ecomorphological and genomic information, we show that exploratory behavior is linked to macrohabitat niche adaptations in Tanganyikan cichlids. Furthermore, we uncovered a correlation between the genotypes at a single-nucleotide polymorphism upstream of the AMPA glutamate-receptor regulatory gene cacng5b and variation in exploratory tendency. We validated this association using behavioral predictions with a neural network approach and CRISPR-Cas9 genome editing.

Resting-state functional network connectivity underlying conscientiousness in school-aged children

Conscientiousness is a personality trait that matures from early childhood to late adolescence, yet little is known about its underlying brain mechanisms during this period. To investigate this, our study examined the resting-state functional network connectivity (rsFNC) of 69 school-aged children (mean age = 10.12 years, range = 9-12) using a whole-brain region-of-interest (ROI) based analysis, based on functional magnetic resonance imaging (fMRI). The results indicated a positive association between conscientiousness and the rsFNC between the fronto-parietal network (FPN) and two brain networks: the somatosensory motor-hand network (SMHN) and the auditory network (AN). However, conscientiousness was negatively associated with the rsFNC between FPN and two other networks: the salience network (SN); the default mode network (DMN). Moreover, our results suggest that the FPN may play a hub role in the neural performance of children's conscientiousness. Intrinsic brain networks, particularly those involved in higher-order cognitive functions, impact children's conscientiousness. Therefore, FPN plays an important role in the development of children's personality, providing insight into the neural mechanisms underlying children's personality.

Personality characteristics, not clinical symptoms, are associated with anhedonia in a community sample: A preliminary investigation

Anhedonia is a salient transdiagnostic psychiatric symptom associated with increased illness severity and chronicity. Anhedonia is also present to varying degrees in non-clinical cohorts. Here, we sought to examine factors influencing expression of anhedonia. Participants (N = 335) were recruited through the Nathan Kline Institute-Rockland Sample, an initiative to deeply phenotype a large community sample across the lifespan. Utilizing a data-driven approach, we evaluated associations between anhedonia severity, indexed by Snaith-Hamilton Pleasure Scale (SHAPS), and 20 physical, developmental, and clinical measures, including Structured Clinical Interview for DSM-IV, Beck Depression Inventory, State-Trait Anxiety Inventory, NEO Five-Factor Inventory-3 (NEO-FFI-3), BMI, Hemoglobin A1C, and demography. Using a bootstrapped AIC-based backward selection algorithm, seven variables were retained in the final model: NEO-FFI-3 agreeableness, extraversion, and openness to experience; BMI; sex; ethnicity; and race. Though median SHAPS scores were greater in participants with psychiatric diagnoses (18.5) than those without (17.0) (U = 12238.5, z = 2.473, p = 0.013), diagnosis and symptom measures were not retained as significant predictors in the final robust linear model. Participants scoring higher on agreeableness, extraversion, and openness to experience reported significantly lower anhedonia. These results demonstrate personality as a mild-to-moderate but significant driver of differences in experiencing pleasure in a community sample.

Do people diagnosed with psychosis spectrum disorders share the same personality space as the general population? Big Five complemented by the proneness to psychotic-like experiences/behaviors

OBJECTIVE

Disintegration is a recently proposed broad, trait-like reconceptualization of the proneness to psychotic-like experiences/behaviors.

METHODS

We tested the assumption that the 6-factor model (Five-Factor traits plus Disintegration) was the most adequate one and that it was invariant across clinical and non-clinical populations. The clinical sample (n = 161) consisted of patients who had at least one psychotic episode, duration of illness less than 10 years, currently in remission. The general population (n = 409) was matched with the patient sample by age, gender, and education. NEO PI-R and DELTA were used to measure personality dimensions in both samples. Invariance of one to six-factor solutions was tested by Exploratory Structural Equation Modeling.

RESULTS

We found that: (a) several criteria for deciding on the number of factors to retain converged to the conclusion that the assumed 6-factor model was the most adequate one, (b) the assumed factorial structure appeared to satisfy the criteria for the scalar invariance across the two samples, (c) all nine Disintegration subdimensions separated from the Big Five, forming the Disintegration factor, and (d) Disintegration was unrelated to Openness.

CONCLUSION

The Big Five personality structure-complemented with disintegration-was invariant across individuals from the general population and patients with psychosis.

Spurious Autobiographical Memory of Psychosis: A Mechanistic Hypothesis for the Resolution, Persistence, and Recurrence of Positive Symptoms in Psychotic Disorders

Psychotic disorders are complex disorders with multiple etiologies. While increased dopamine synthesis capacity has been proposed to underlie psychotic episodes, dopamine-independent processes are also involved (less responsive to dopamine receptor-blocking medications). The underlying mechanism(s) of the reduction in antipsychotic responsiveness over time, especially after repeated relapses, remain unclear. Despite the consistent evidence of dopamine overactivity and hippocampal volume loss in schizophrenia, few accounts have been provided based on the interactive effect of dopamine on hippocampal synapse plasticity mediating autobiographical memory processes. The present hypothesis builds upon previous works showing the potential effects of dopamine overactivity on hippocampal-mediated neuroplasticity underlying autobiographical memory, alongside known patterns of autobiographical memory dysfunction in psychosis. We propose that spurious autobiographical memory of psychosis (SAMP) produced during active psychosis may be a key mechanism mediating relapses and treatment non-responsiveness. In a hyperdopaminergic state, SAMP is expected to be generated at an increased rate during active psychosis. Similar to other memories, it will undergo assimilation, accommodation, and extinction processes. However, if SAMP fails to integrate with existing memory, a discontinuity in autobiographical memory may result. Inadequate exposure to normalizing experiences and hyposalience due to overmedication or negative symptoms may also impede the resolution of SAMP. Residual SAMP is hypothesized to increase the propensity for relapse and treatment non-responsiveness. Based on recent findings on the role of dopamine in facilitating hippocampal synapse plasticity and autobiographical memory formation, the SAMP hypothesis is consistent with clinical observations of DUP effects, including the repetition of contents in psychotic relapses as well as the emergence of treatment non-responsiveness after repeated relapses. Clinical implications of the hypothesis highlight the importance of minimizing active psychosis, integrating psychosis memory, avoiding over-medication, and fostering normalizing experiences.

Early Motor Developmental Milestones and Personality Traits in Midlife: A 50-Year Follow-Up Study

Background The purpose of this study was to investigate if infants' age at attaining motor developmental milestones is associated with the big five personality traits 50 years later. Methods Mothers of 8395 infants from the Copenhagen Perinatal Cohort recorded a total of 12 motor developmental milestones during the first year of their infant's life. Information on at least one milestone was available for 1307 singletons with adult follow-up scores on the NEO-Five-Factor Inventory. The mean age at personality testing was 50.1 years. Results Slower attainment of motor milestones was associated with increased neuroticism and lower conscientiousness in midlife. All 12 motor developmental milestones explained a total of 2.4% of the variance in neuroticism, while they explained 3.2% of the variance in conscientiousness. These results remained significant after adjustment for the included family and perinatal covariates, as well as adult intelligence. Discussion The personality trait of neuroticism is a general risk factor for psychopathology and has in young adulthood been found to be associated with early motor development. However, evidence on associations of motor developmental milestones with other personality traits has been non-existent. These findings suggest that delays in early motor development may not only characterise individuals with later psychopathology, including schizophrenia, but may also be associated with personality traits such as neuroticism and conscientiousness through the life course.

Maladaptive personality traits in patients with recent-onset psychosis: A case-control study using the Personality Inventory for the DSM-5 (PID-5)

BACKGROUND

The relationship between maladaptive personality traits and psychotic disorders in the early stages of disease has not been thoroughly investigated, even though it is essential for developing prevention and early intervention strategies.

METHODS

The five domains and the 25 facets of the Personality Inventory for DSM-5 (PID-5) were compared between 102 patients with recent-onset psychosis (ROP) and 116 community subjects (C) with a general linear model including age and sex in the analyses. In addition, multiple linear regression models were used to identify which factors associated with the PID-5 domains in ROP, and correlation analyses were used to explore the relationship between personality traits.

RESULTS

Patients with ROP, compared to C, exhibited higher scores in four out of the five domains with medium effect sizes (Cohen's f² ≥ 0.15) in two of them: negative affect (NA, p = 0.013, f² = 0.04), detachment (DET, p < 0.001, f² = 0.15), disinhibition (DIS, p < 0.001, f² = 0.14) and psychoticism (PSY, p < 0.001, f² = 0.16). Significant group differences were observed in 15 of the 25 facets and the largest effects were observed in the facets of withdrawal (p ≤ 0.001, f² = 0.20), irresponsibility (p < 0.001, f² = 0.23) and unusual beliefs (p = 0.001, f² = 0.22). Interestingly, being on antidepressants and high scores on the positive subscale of the Positive and Negative Syndrome Scale (PANSS) were associated with high scores of NA, antagonism (ANT) and PSY.

CONCLUSIONS

Maladaptive personality traits were prominent in persons with ROP. These findings suggest that personality traits might play a role in vulnerability to psychosis and highlight the importance of evaluating personality in the early stages of psychosis.

Role of the Neuropeptide S System in Emotionality, Stress Responsiveness and Addiction-Like Behaviours in Rodents: Relevance to Stress-Related Disorders

The neuropeptide S (NPS) and its receptor (NPSR1) have been extensively studied over the last two decades for their roles in locomotion, arousal/wakefulness and anxiety-related and fear-related behaviours in rodents. However, the possible implications of the NPS/NPSR1 system, especially those of the single nucleotide polymorphism (SNP) rs324981, in stress-related disorders and substance abuse in humans remain unclear. This is possibly due to the fact that preclinical and clinical research studies have remained separated, and a comprehensive description of the role of the NPS/NPSR1 system in stress-relevant and reward-relevant endpoints in humans and rodents is lacking. In this review, we describe the role of the NPS/NPSR1 system in emotionality, stress responsiveness and addiction-like behaviour in rodents. We also summarize the alterations in the NPS/NPSR1 system in individuals with stress-related disorders, as well as the impact of the SNP rs324981 on emotion, stress responses and neural activation in healthy individuals. Moreover, we discuss the therapeutic potential and possible caveats of targeting the NPS/NPSR1 system for the treatment of stress-related disorders. The primary goal of this review is to highlight the importance of studying some rodent behavioural readouts modulated by the NPS/NPSR1 system and relevant to stress-related disorders.

Bifactor Structure of the Schizotypal Personality Questionnaire Across the Schizotypy Spectrum

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

The effects of patient personality traits and family cohesion on the treatment delay for patients with first-episode schizophrenia spectrum disorder

AIM

The duration of untreated psychosis (DUP) is an important prognostic indicator of schizophrenia. We explored the effects of patient personality and family relationships on delayed schizophrenia treatment.

METHODS

We prospectively included data from 169 patients diagnosed with first-episode schizophrenia. Personality traits were investigated using the Big Five Inventory (BFI-10) and family relationship was assessed employing the Family Adaptability and Cohesion Evaluation Scale-III (FACES-III). We explored patient clinical characteristics using the Positive and Negative Syndrome Scale (PANSS) and the Social and Occupational Functioning Scale (SOFAS). The DUP was defined as the time between the first appearance of psychotic symptoms and commencement of adequate antipsychotic treatment. Subjects were divided into two groups by the 3-month median DUP cutoff.

RESULTS

The average and median DUPs were 12 and 3 months, respectively. A longer DUP was associated with older age, a higher PANSS score, and a lower SOFAS score. The frequency of suicide attempts tended to be higher in the delayed treatment group (P = .055). The delayed treatment group scored significantly higher in conscientiousness factor of the BFI-10 and scored significantly lower family cohesion and adaptability factors of the FACES-III. Logistic regression showed that a longer DUP was significantly associated with higher-level conscientiousness on the BFI-10 and poorer family cohesion on the FACES-III.

CONCLUSION

Treatment delay was associated with reduced family cohesion and higher patient conscientiousness, suggesting that the family plays a crucial role in terms of patient access to mental health services when early psychotic symptoms appear.

Identification of pleiotropy at the gene level between psychiatric disorders and related traits

Major mental disorders are highly prevalent and make a substantial contribution to the global disease burden. It is known that mental disorders share clinical characteristics, and genome-wide association studies (GWASs) have recently provided evidence for shared genetic factors as well. Genetic overlaps are usually identified at the single-marker level. Here, we aimed to identify genetic overlaps at the gene level between 7 mental disorders (schizophrenia, autism spectrum disorder, major depressive disorder, anorexia nervosa, ADHD, bipolar disorder and anxiety), 8 brain morphometric traits, 2 cognitive traits (educational attainment and general cognitive function) and 9 personality traits (subjective well-being, depressive symptoms, neuroticism, extraversion, openness to experience, agreeableness and conscientiousness, children's aggressive behaviour, loneliness) based on publicly available GWASs. We performed systematic conditional regression analyses to identify independent signals and select loci associated with more than one trait. We identified 48 genes containing independent markers associated with several traits (pleiotropy at the gene level). We also report 9 genes with different markers that show independent associations with single traits (allelic heterogeneity). This study demonstrates that mental disorders and related traits do show pleiotropy at the gene level as well as the single-marker level. The identification of these genes might be important for prioritizing further deep genotyping, functional studies, or drug targeting.

Personality Traits in Individuals with the Dual Diagnosis of Psychosis and Substance Use Disorders: A Comprehensive Review and Meta-Analysis

Substance abuse comorbidity is highly prevalent and is linked to detrimental outcomes in individuals with psychotic disorder, but the role of personality traits as the underlying mechanism is being increasingly underscored. This study aimed to profile temperamental risks of comorbid substance use disorder in psychotic disorders by performing meta-analyses on personality trait differences between psychotic disorders with comorbidity (dual diagnosis; DD) and without it (psychotic disorders; PSD). Methods: A systematic review of English articles using PubMed, MEDLINE, Scopus, Google Scholar, and ProQuest Dissertation and Theses. Only original empirical studies including participants with diagnosis of psychotic disorders based on structured diagnostic interviews, with and without substance use disorder evaluated with reliable and valid tests were included. Articles were independently extracted by two authors using predefined data fields, including study quality indicators. All pooled analyses were based on random-effect models. Thirteen studies (N = 885) met our inclusion criteria. All effect-size estimates were calculated based on means and standard deviations of included measures. Separate effect size estimates were obtained for four traits in the UPPS model (negative urgency, low premeditation, low perseverance, sensation seeking), four traits in the HS model (unconscientious disinhibition, negative affect, disagreeable disinhibition, positive affect) and trait anhedonia. Results: Negative urgency (four studies with 262 participants; ES = 0.59; 95% confidence interval [CI] [0.34, 0.84]), low premeditation (five studies with 349 participants; ES = 0.60; 95% CI [0.39, 0.80]), sensation seeking (seven studies with 550 participants; ES = 0.63; 95% CI [0.17, 1.09]) and unconscientious disinhibition (five studies with 291 participants; ES = 0.36; 95% CI [0.13, 0.59]) were elevated in DD than PSD. Heterogeneity of sensation seeking was significant (I² = 86.2%). Conclusions: The findings of the current meta-analysis highlight a unique profile of impulsive and externalizing trait personality domains pertaining to DD. The study emphasizes the importance of emotion regulation interventions targeting impulsivity or negative affect (i.e. negative urgency, low premeditation) in substance abuse comorbidity patients.

Validity and utility of Hierarchical Taxonomy of Psychopathology (HiTOP): I. Psychosis superspectrum

The Hierarchical Taxonomy of Psychopathology (HiTOP) is a scientific effort to address shortcomings of traditional mental disorder diagnoses, which suffer from arbitrary boundaries between psychopathology and normality, frequent disorder co-occurrence, heterogeneity within disorders, and diagnostic instability. This paper synthesizes evidence on the validity and utility of the thought disorder and detachment spectra of HiTOP. These spectra are composed of symptoms and maladaptive traits currently subsumed within schizophrenia, other psychotic disorders, and schizotypal, paranoid and schizoid personality disorders. Thought disorder ranges from normal reality testing, to maladaptive trait psychoticism, to hallucinations and delusions. Detachment ranges from introversion, to maladaptive detachment, to blunted affect and avolition. Extensive evidence supports the validity of thought disorder and detachment spectra, as each spectrum reflects common genetics, environmental risk factors, childhood antecedents, cognitive abnormalities, neural alterations, biomarkers, and treatment response. Some of these characteristics are specific to one spectrum and others are shared, suggesting the existence of an overarching psychosis superspectrum. Further research is needed to extend this model, such as clarifying whether mania and dissociation belong to thought disorder, and explicating processes that drive development of the spectra and their subdimensions. Compared to traditional diagnoses, the thought disorder and detachment spectra demonstrated substantially improved utility: greater reliability, larger explanatory and predictive power, and higher acceptability to clinicians. Validated measures are available to implement the system in practice. The more informative, reliable and valid characterization of psychosis-related psychopathology offered by HiTOP can make diagnosis more useful for research and clinical care.

Personality and the Expression of Symptomatology in Schizophrenia and Bipolar Disorder

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

Common Taxonomy of Traits and Symptoms: Linking Schizophrenia Symptoms, Schizotypy, and Normal Personality

The associations among normal personality and many mental disorders are well established, but it remains unclear whether and how symptoms of schizophrenia and schizotypal traits align with the personality taxonomy. This study examined the joint factor structure of normal personality, schizotypy, and schizophrenia symptoms in people with psychotic disorders (n = 288) and never-psychotic adults (n = 257) in the Suffolk County Mental Health Project. First, we evaluated the structure of schizotypal (positive schizotypy, negative schizotypy, and mistrust) and normal traits. In both the psychotic-disorder and never-psychotic groups, the best-fitting model had 5 factors: neuroticism, extraversion, conscientiousness, agreeableness, and psychoticism. The schizotypy traits were placed on different dimensions: negative schizotypy went on (low) extraversion, whereas positive schizotypy and mistrust went on psychoticism. Next, we added symptoms to the model. Numerous alternatives were compared, and the 5-factor model remained best-fitting. Reality distortion (hallucinations and delusions) and disorganization symptoms were placed on psychoticism, and negative symptoms were placed on extraversion. Models that separated symptom dimensions from trait dimensions did not fit well, arguing that taxonomies of symptoms and traits are aligned. This is the first study to show that symptoms of psychosis, schizotypy, and normal personality reflect the same underlying dimensions. Specifically, (low) extraversion, negative schizotypy, and negative symptoms form one spectrum, whereas psychoticism, positive schizotypy, and positive and disorganized symptoms form another. This framework helps to understand the heterogeneity of psychosis and comorbidity patterns found in psychotic disorders. It also underscores the importance of traits to understanding these disorders.

Early maladaptive schemas in patients with schizophrenia and non-patients with high and low schizotypal traits and their differences based on depression severity

BACKGROUND

The aims of this study were to predict positive and negative symptoms of psychosis via early maladaptive schemas (EMSs) in patients with schizophrenia (SZ); to compare EMSs among SZ patients, non-patients with high schizotypal traits, and non-patients with low schizotypal traits; and to compare EMSs among subgroups concerning depression severity.

METHODS

We applied three groups of participants including SZ patients (n = 105), non-patients with low schizotypal traits (n = 90), and non-patients with high schizotypal traits (n = 90). Participants completed the Young Schema Questionnaire-Short Form (YSQ-SF), the Positive and Negative Syndrome Scale (PANSS), the Schizotypal Personality Scale (STA), and the Beck Depression Inventory-II (BDI-II).

RESULTS

The results indicated that the mistrust/abuse and social isolation schemas were significant predictors of positive and negative symptoms in SZ patients respectively. SZ patients and non-patients with high schizotypal traits exceeded non-patients with low schizotypal traits on all EMSs. There were no differences between SZ patients and non-patients with high schizotypal traits regarding EMSs. In the subgroups with high depression, SZ patients showed higher levels of EMSs than non-patients with low and high schizotypal traits. In the subgroups with low depression, both SZ patients and non-patients with high schizotypal traits had higher scores on EMSs than non-patients with low schizotypal traits.

CONCLUSION

The findings suggest that mistrust/abuse and social isolation may be specific to psychosis symptoms. Also, SZ and schizotypal traits may overlap in relation to EMSs. In addition, the activated EMSs may contribute to high depression in SZ.

[Personality disorders and schizophrenic defect (problem of comorbidity)]

AIM

To test the main hypothesis that the deficit phenomena in schizophrenia act not in the 'pure' form, but in the form of aggravating personality characteristics, forming so-called 'common' syndromes with personality disorders (PD).

MATERIAL AND METHODS

The results of the psychopathological study (with the use of psychometric methods) of deficit disorders in a sample of 170 patients with schizophrenia and schizophrenia spectrum disorders (63 men, 107 women) are presented in relation to the abnormal structure of premorbid personality (PD of clusters A, B, C). An analysis of negative symptoms according to the comparability of defect to the profile of premorbid personality made it possible to distinguish three groups of deficit states associated with PD - 'common syndromes': defensive schizoidy by the type of deficit schizoid and expansive schizoidy by the type of 'verschroben' (cluster A); pathological hysterical infantilism, malignant hysteria and defective erotomania (cluster B); pseudo-psychasthenia and pathological rationalism (cluster C).

RESULTS

It has been found that the symptomatology of 'common syndromes' is subject to patterns reflecting the dichotomy of the basic defect. This pattern is valid not only for one single cluster of PD, but extends to all psychopathy-like disorders, regardless of their affiliation with a particular cluster. The pathocharacterological component of the 'common syndromes' coexisting with the deficit symptom complexes is subject to the basic deficit component of the defect and is separated into polar dimensions (defensive-expansive) within specific clusters of PD, and then unified in accordance with the dichotomy of schizophrenic defect in categories with the predominance of emotional or apathoabulic disorders.

CONCLUSION

Psychopathy-like symptom complexes in the space of 'common syndromes' can be qualified as a psychopathological construct secondary to basic deficit disorders, and their isolation as an independent entity of negative disorders appears to be unjustified.

Personality Pathology and Schizophrenia

The interaction of personality pathology and schizophrenia has conceptually been a topic of considerable interest in psychiatry. Recent advances in taxonomy and assessment of relevance to the clinician and researcher is presented. Cluster A and avoidant personality disorders are regarded as risk factors or antecedents for the development of schizophrenia. Some features of borderline personality disorder may resemble schizophrenia. With both a hierarchical structure and symptom-focused classification systems, personality pathology and personality disorder comorbidities can be overlooked. They can remain untreated because they are seen as part of the psychotic syndrome or superseded. A case formulation of a patient with schizophrenia is likely enriched by considering both these facets and may highlight comorbid personality disorder that warrants independent treatment.

Genome-wide association study results for educational attainment aid in identifying genetic heterogeneity of schizophrenia

Higher educational attainment (EA) is negatively associated with schizophrenia (SZ). However, recent studies found a positive genetic correlation between EA and SZ. We investigate possible causes of this counterintuitive finding using genome-wide association study results for EA and SZ (N = 443,581) and a replication cohort (1169 controls; 1067 cases) with deeply phenotyped SZ patients. We find strong genetic dependence between EA and SZ that cannot be explained by chance, linkage disequilibrium, or assortative mating. Instead, several genes seem to have pleiotropic effects on EA and SZ, but without a clear pattern of sign concordance. Using EA as a proxy phenotype, we isolate FOXO6 and SLITRK1 as novel candidate genes for SZ. Our results reveal that current SZ diagnoses aggregate over at least two disease subtypes: one part resembles high intelligence and bipolar disorder (BIP), while the other part is a cognitive disorder that is independent of BIP.

Glutamate Concentration in the Superior Temporal Sulcus Relates to Neuroticism in Schizophrenia

Clinical studies suggest aberrant neurotransmitter concentrations in the brains of patients with schizophrenia (SCZ). Numerous studies have indicated deviant glutamate concentrations in SCZ, although the findings are inconsistent. Moreover, alterations in glutamate concentrations could be linked to personality traits in SCZ. Here, we examined the relationships between personality dimensions and glutamate concentrations in a voxel encompassing the occipital cortex (OCC) and another voxel encompassing the left superior temporal sulcus (STS). We used proton magnetic resonance spectroscopy to examine glutamate concentrations in the OCC and the STS in 19 SCZ and 21 non-psychiatric healthy control (HC) participants. Personality dimensions neuroticism, extraversion, openness, agreeableness and conscientiousness were assessed using the NEO-FFI questionnaire. SCZ compared to HC showed higher glutamate concentrations in the STS, reduced extraversion scores, and enhanced neuroticism scores. No group differences were observed for the other personality traits and for glutamate concentrations in the OCC. For the SCZ group, glutamate concentrations in STS were negatively correlated with the neuroticism scores [r = -0.537, p = 0.018] but this was not found in HC [r(19) = 0.011, p = 0.962]. No other significant correlations were found. Our study showed an inverse relationship between glutamate concentrations in the STS and neuroticism scores in SCZ. Elevated glutamate in the STS might serve as a compensatory mechanism that enables patients with enhanced concentrations to control and prevent the expression of neuroticism.

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

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

Social anhedonia and gamma band abnormalities as a composite/multivariate endophenotype for schizophrenia: a dense array EEG study

AIM

Social anhedonia and gamma band oscillations are proposed as a promising endophenotype for schizophrenia (SZ). The aim was to assess whether social anhedonia and spontaneous gamma band oscillations could be used as multivariate/composite endophenotypic measures for SZ.

METHODS

Sixty consented subjects, of which 20 remitted SZ patients, 20 unaffected siblings of patients with schizophrenia (US) and 20 healthy controls (HC) were recruited for the study. The Revised Social Anhedonia Scale, Temporal Experience of Pleasure Scale and the Schizotypal Personality Questionnaire assessed social anhedonia, temporal experience of pleasure and schizotypal features. All participants underwent awake, resting state 192-channel dense array electroencephalographic recording. Gamma spectral power and coherence were calculated. We performed chi-square test, one-way analysis of variance, Pearsons correlation coefficient and step-by-step linear discriminant functional analysis.

RESULTS

Social anhedonia was significantly higher and anticipatory aspects of pleasure were significantly lower in both SZ and US compared with HC. US scored significantly higher than HC in the Schizotypal Personality Questionnaire. Spectral power of high gamma band (>70 Hz) was significantly lower over the right temporo-parietal and midline regions in both SZ and US than HC. We accurately classified (85%) three groups when social anhedonia, high gamma band spectral power of midline, right frontal and right fronto-temporal interhemispheric gamma coherence were considered as composite measures rather than each variable representing independently.

CONCLUSION

We propose region-specific high gamma spectral 'power and coherence' and social anhedonia as composite/multivariate measures could be a useful measure in distinguishing schizophrenia patients and unaffected siblings from healthy controls.

Openness to experience shortens duration of untreated psychosis in Serbian clinical population

AIM

To determine duration of untreated psychosis (DUP) in patients with schizophrenia-spectrum disorders from Serbia and to analyse factors that potentially contribute to the treatment delay, with focus on personality traits.

METHODS

Fifty seven patients (males 54.4%; age = 29.9 ± 6.0 yrs; age at the illness onset = 24.9 ± 5.1 yrs; IQ = 93.5 ± 12.2) were included. The assessment consisted of Nottingham Onset Schedule (NOS), Premorbid Adjustment Scale (PAS) and NEO Personality Inventory (NEO-PI-R). We used Cox regression model to evaluate relationship between DUP and explanatory variables.

RESULTS

Based on the most restrictive definition, the length of DUP in our sample was 77.8 ± 120.6 weeks (MED = 25.0 weeks). DUP was negatively associated with openness to experience (B = -0.804, P = 0.024).

CONCLUSIONS

We report the first evidence of DUP in Serbia, emphasizing that the personality domains are likely to impact the use of mental health care in persons with psychosis.

Reliving, Replaying Lived Experiences Through Auditory Verbal Hallucinations: Implications on Theories and Management

Objective: This study aims to understand the impact of negative life experience (NLE) in auditory hallucinations (AHs) and explain the heterogeneity in phenomenology of auditory verbal hallucinations (AVHs). Method: In depth interviews were conducted with 21 individuals (7 males and 14 females) experiencing AHs and accessing mental health treatment services at a not-for-profit organization. Maximum variation purposive sampling technique was used to select the sample to ensure variegation is accounted for and was collected until saturation of themes data was obtained. Results: Various different forms and functions of hallucinations are obtained with an evident pattern that links voices back to the NLE of the individual. Implications for therapeutic methods focusing on distress arising from said NLE is emphasized. Conclusions: The results obtained from this study implicate NLEs as a contributing factor in the development and maintenance of hallucinations. Sociocultural factors act as a catalyst with psychological factors creating distress and contributing to the voice-hearing experience. Treatment strategies must thus focus on content of voices and past experiences of the individual to promote recovery. A model toward conceptualization of the diversity in phenomenology is put forth.

The Relationship Between Big Five Personality Traits and Psychotic Experience in a Large Non-clinical Youth Sample: The Mediating Role of Emotion Regulation

Objective: Despite a long history of interest in personality traits and psychosis, the association between personality traits and psychotic experiences in the general population is not yet well understood. One possible factor that could influence the degree of distress from psychotic experiences is emotion regulation. The purpose of this study was to explore whether the association between personality and psychotic symptoms is already apparent in non-clinical youth as well as the mediating role of emotion regulation strategies between personality traits and psychotic experiences. Methods: Three thousand one hundred and forty seven college students were surveyed via self-report questionnaires measuring the Five-Factor model of personality, emotion regulation strategies, and psychotic experiences. Results: Neuroticism was found to be significantly positively correlated with psychotic experiences, while Extraversion, Openness, Agreeableness, and Conscientiousness were found to be significantly negatively correlated. Both the suppression and reappraisal strategies mediated the relationship between personality traits and psychotic experiences. Conclusion: Our findings suggest that youth with certain personality traits are more likely to have psychotic experiences. The reappraisal emotion regulation strategy could serve as a protective factor against the distress of psychotic experiences.

Identification of genetic loci shared between schizophrenia and the Big Five personality traits

Schizophrenia is associated with differences in personality traits, and recent studies suggest that personality traits and schizophrenia share a genetic basis. Here we aimed to identify specific genetic loci shared between schizophrenia and the Big Five personality traits using a Bayesian statistical framework. Using summary statistics from genome-wide association studies (GWAS) on personality traits in the 23andMe cohort (n = 59,225) and schizophrenia in the Psychiatric Genomics Consortium cohort (n = 82,315), we evaluated overlap in common genetic variants. The Big Five personality traits neuroticism, extraversion, openness, agreeableness and conscientiousness were measured using a web implementation of the Big Five Inventory. Applying the conditional false discovery rate approach, we increased discovery of genetic loci and identified two loci shared between neuroticism and schizophrenia and six loci shared between openness and schizophrenia. The study provides new insights into the relationship between personality traits and schizophrenia by highlighting genetic loci involved in their common genetic etiology.

Personality traits predicting quality of life and overall functioning in schizophrenia

INTRODUCTION

Clinical symptoms and sociodemographic variables predict level of functioning and quality of life in patients with schizophrenia. However, few studies have examined the effect of personality traits on quality of life and overall functioning in schizophrenia. Personality traits are premorbid to illness and may predict the way patients experience schizophrenia. The aim of this study was to examine the individual and additive effects of two core personality traits-neuroticism and extraversion-on quality of life and functioning.

METHODS

Patients with schizophrenia-spectrum disorders (n=153) and healthy controls (n=125) completed personality and quality of life questionnaires. Global functioning was assessed during a clinician-administered structured interview. Neuroticism and extraversion scores were analyzed both as continuous variables and as categorical extremes (High versus Normal Neuroticism, Low versus Normal Extraversion).

RESULTS

Quality of life was significantly associated with neuroticism, extraversion, and the neuroticism×diagnosis and extraversion×diagnosis interactions. For patients, a lower neuroticism score (in the normal range) was associated with quality of life scores comparable to controls; whereas high neuroticism scores in patients were associated with the lowest quality of life. For overall functioning, only diagnosis had a significant effect.

CONCLUSION

Neuroticism modulates quality of life and may provide an important key to improving the life of patients with schizophrenia.

The Relationship Between the Personality Inventory for the DSM-5 (PID-5) and the Psychotic Disorder in a Clinical Sample

Recent studies have successfully investigated the validity of the DSM-5 Alternative Model for Personality Disorders. In a final sample of 174 psychiatric patients, the present study examined the relationship between the Personality Inventory for the DSM-5 (PID-5) and syndromal psychosis. Results showed that patients diagnosed with versus without a psychotic disorder significantly differed on all PID-5 domains except Antagonism. Discriminant function analysis indicated that lower Detachment, lower Negative Affect, lower Disinhibition, and higher Psychoticism best discriminated patients with a psychotic disorder from patients with other psychiatric conditions. Subsequent stepwise discriminant analysis on all facet scales of the contributing PID-5 domains revealed that higher Unusual Beliefs, lower Depressivity, and lower Distractibility contributed the most to this differentiation. PID-5 Psychoticism scores showed moderate correlations with current psychotic symptoms and were not influenced by dose of antipsychotic medication. Our results support the ability of the PID-5 to discriminate between patients with and without psychotic disorder.

Does personality influence job acquisition and tenure in people with severe mental illness enrolled in supported employment programs?

BACKGROUND

When employment difficulties in people with severe mental illness (SMI) occur, it could be partly linked to issues not specific to SMI, such as personality traits or problems. Despite the fact that personality has a marked influence on almost every aspect of work behavior, it has scarcely been investigated in the context of employment for people with SMI.

AIMS

We aimed to evaluate if personality was more predictive than clinical variables of different competitive work outcomes, namely acquisition of competitive employment, delay to acquisition and job tenure.

METHOD

A sample of 82 people with a SMI enrolled in supported employment programs (SEP) was recruited and asked to complete various questionnaires and interviews. Statistical analyses included logistic regressions and survival analyses (Cox regressions).

RESULTS

Prior employment, personality problems and negative symptoms are significantly related to acquisition of a competitive employment and to delay to acquisition whereas the conscientiousness personality trait was predictive of job tenure.

CONCLUSION

Our results point out the relevance of personality traits and problems as predictors of work outcomes in people with SMI registered in SEP. Future studies should recruit larger samples and also investigate these links with other factors related to work outcomes.

Hopes and Expectations Regarding Genetic Testing for Schizophrenia Among Young Adults at Clinical High-Risk for Psychosis

Genetic tests for schizophrenia could introduce both risks and benefits. Little is known about the hopes and expectations of young adults at clinical high-risk for psychosis concerning genetic testing for schizophrenia, despite the fact that these youth could be among those highly affected by such tests. We conducted semistructured interviews with 15 young adults at clinical high-risk for psychosis to ask about their interest, expectations, and hopes regarding genetic testing for schizophrenia. Most participants reported a high level of interest in genetic testing for schizophrenia, and the majority said they would take such a test immediately if it were available. Some expressed far-reaching expectations for a genetic test, such as predicting symptom severity and the timing of symptom onset. Several assumed that genetic testing would be accompanied by interventions to prevent schizophrenia. Participants anticipated mixed reactions on finding out they had a genetic risk for schizophrenia, suggesting that they might feel both a sense of relief and a sense of hopelessness. We suggest that genetic counseling could play an important role in counteracting a culture of genetic over-optimism and helping young adults at clinical high-risk for psychosis understand the limitations of genetic testing. Counseling sessions could also invite individuals to explore how receiving genetic risk information might impact their well-being, as early evidence suggests that some psychological factors help individuals cope, whereas others heighten distress related to genetic test results.

Personality traits in established schizophrenia: aspects of usability and differences between patients and controls using the Swedish universities Scales of Personality

BACKGROUND

Personality is considered as an important aspect that can affect symptoms and social function in persons with schizophrenia. The personality questionnaire Swedish universities Scales of Personality (SSP) has not previously been used in psychotic disorder.

AIMS

To investigate if SSP has a similar internal consistency and factor structure in a psychosis population as among healthy controls and if patients with psychotic disorders differ from non-psychotic individuals in their responses to the SSP.

METHODS

Patients with psychotic disorders (n = 107) and healthy controls (n = 119) completed SSP. SSP scores were analyzed for internal consistency and case-control differences by Cronbach's alfa and multiple analysis of covariance, respectively.

RESULTS

Internal consistencies among patients were overall similar to that of controls. The patients scored significantly higher in seven (Somatic trait anxiety, Psychic trait anxiety, Stress susceptibility, Lack of assertiveness, Detachment, Embitterment, Mistrust) and lower in three (Physical trait aggression, Verbal trait aggression, Adventure seeking) of the 13 scales of the inventory. In three scales (Impulsiveness, Social desirability and Trait irritability) there was no significant difference between the scoring of patients and healthy controls.

CONCLUSION

The reliability estimates suggest that SSP can be used by patients with psychotic disorders in stable remission. Patients score higher on neuroticism-related scales and lower on aggression-related scales than controls, which is in accordance with earlier studies where other personality inventories were used.

Co-morbidity of personality disorder in schizophrenia among psychiatric outpatients in China: data from epidemiologic survey in a clinical population

BACKGROUND

The reported rates of personality disorder (PD) in subjects with schizophrenia (SZ) are quite varied across different countries, and less is known about the heterogeneity of PD among subjects with SZ. We examined the co-morbidity of PD among patients who are in the stable phase of SZ.

METHOD

850 subjects were randomly sampled from patients diagnosed with SZ in psychiatric and psycho-counseling clinics at Shanghai Mental Health Center. Co-morbidity of PDs was assessed through preliminary screening and patients were administered several modules of the SCID-II. Evidence of heterogeneity was evaluated by comparing patients diagnosed with SZ with those who presented with either affective disorder or neurosis (ADN).

RESULTS

204 outpatients (24.0 %) in the stable phase of SZ met criteria for at least one type of DSM-IV PD. There was a higher prevalence of Cluster-A (odd and eccentric PD) and C (anxious and panic PD) PDs in SZ (around 12.0 %). The most prevalent PD was the paranoid subtype (7.65 %). Subjects with SZ were significantly more likely to have schizotypal PD (4.4 % vs. 2.1 %, p = 0.003) and paranoid PD (7.6 % vs. 5.4 %, p = 0.034), but much less likely to have borderline, obsessive-compulsive, depressive, narcissistic and histrionic PD.

CONCLUSIONS

These findings suggest that DSM-IV PD is common in patients with SZ than in the general population. Patterns of co-morbidity with PDs in SZ are different from ADN.

The Five-Factor Model personality traits in schizophrenia: A meta-analysis

Personality is one of important factors in the pathogenesis of schizophrenia because it affects patients' symptoms, cognition and social functioning. Several studies have reported specific personality traits in patients with schizophrenia compared with healthy subjects. However, the results were inconsistent among studies. The NEO Five-Factor Inventory (NEO-FFI) measures five personality traits: Neuroticism (N), Extraversion (E), Openness (O), Agreeableness (A) and Conscientiousness (C). Here, we performed a meta-analysis of these personality traits assessed by the NEO-FFI in 460 patients with schizophrenia and 486 healthy subjects from the published literature and investigated possible associations between schizophrenia and these traits. There was no publication bias for any traits. Because we found evidence of significant heterogeneity in all traits among the studies, we applied a random-effect model to perform the meta-analysis. Patients with schizophrenia showed a higher score for N and lower scores for E, O, A and C compared with healthy subjects. The effect sizes of these personality traits ranged from moderate to large. These differences were not affected by possible moderator factors, such as gender distribution and mean age in each study, expect for gender effect for A. These findings suggest that patients with schizophrenia have a different personality profile compared with healthy subjects.

Personality and coping in first episode psychosis linked to mental health care use

A body of literature focuses on associations of neuroticism, extraversion, passive coping and active coping with the course of psychotic illness. Less is known about other personality and coping variables - and underlying causal mechanisms between variables remain unclear. We explored causal effects from personality, coping and symptoms on mental health care consumption over two years in 208 first episode patients. Causal inference search algorithms lead to formation of a hypothetical causal model based on presumptions on (non-)mutuality between variables and consistent with data. Structural equation modelling estimated effect sizes conditionally on the causal model. Our observed model implies that none of the coping or personality variables have any effect on the number of days of hospitalisation, whereas general psychopathology symptoms do have a direct positive effect. For ambulatory care it is proposed that openness to experience, depressive symptoms and age have direct positive effects. Reassuring thoughts as a coping strategy seems to have a direct negative effect on the use of ambulatory care and mediates indirect effects of other personality and coping variables on ambulatory care. Furthermore, while previously established relations between personality and symptoms are confirmed by our model, it challenges traditional ideas about causation between personality and symptoms.

Personality domains, duration of untreated psychosis, functioning, and symptom severity in first-episode psychosis

OBJECTIVES

Early-course psychotic disorders have been extensively studied in terms of phenomenology, but little is known about the influence of personality traits on clinical features of first-episode psychosis. The aim of this study was to explore how the "big five" personality domains (neuroticism, extraversion, openness, agreeableness, and conscientiousness) are associated with treatment delay (duration of untreated psychosis, DUP), functioning, and positive and negative symptom severity.

METHODS

Data for these analyses were obtained from 104 participants enrolled from psychiatric inpatient units in Atlanta, Georgia, between August 2008 and March 2011. The NEO Five-Factor Inventory (NEO-FFI) was used to assess personality domains, and all other variables were measured in a standardized and rigorous manner using psychometrically sound instruments. Correlational analyses and multiple linear regressions were carried out to examine the strength of associations between variables of interest.

RESULTS

Findings indicated that except for openness, all of the other personality variables contributed to some extent to the variance in DUP. Conscientiousness was positively correlated with functioning. Agreeableness was independently negatively associated with positive symptom severity and extraversion was independently negatively correlated with negative symptom severity.

CONCLUSIONS

We report the first evidence suggesting that DUP is in part driven by personality domains. Functioning and symptom severity are also associated with those domains. Personality should be taken into account in order to better understand the phenomenology of early-course psychotic disorders as well as treatment-seeking behaviors.

Three year stability of Five-Factor Model personality traits in relation to changes in symptom levels in patients with schizophrenia or related disorders

Five-Factor Model (FFM) personality traits are related to a wide range of clinical outcome in patients with psychotic disorders. However, it is not sufficiently clear whether psychotic illness, particularly fluctuation in negative symptoms and psychotic relapse, affects personality. The current study examined the 3-year temporal stability of FFM traits in 91 patients with non-affective psychotic disorders with a maximum duration of illness of 10 years and 32 control subjects without a (family member with) a diagnosis of psychotic illness. In patients, change in negative symptoms predicted changes in Neuroticism and (inversely) in Extraversion and Openness. However, when correcting for depressive symptoms, negative symptoms no longer predicted change in any FFM trait. Clinical characteristics, such as psychotic relapse, were also not found to be related to change in FFM traits. Patients showed a slight increase in Conscientiousness levels, the other FFM traits showed mean-level stability. Rank-order stability of the FFM traits was moderate to strong, although weaker for Neuroticism in patients. Our findings indicate that psychotic symptoms exert limited effect on the stability of FFM traits in patients with psychotic disorders. Consistent with general population findings, one should guard against state-trait confusion between Neuroticism/Extraversion and depression.

Personality trait correlates of color preference in schizophrenia

BACKGROUND

The goal of the present study was to evaluate the color preferences of patients with schizophrenia and their correlations with personality traits.

METHODOLOGY

Sixty-three patients with schizophrenia and 59 healthy volunteers were asked to undertake the color preference and the Zuckerman-Kuhlman Personality Questionnaire (ZKPQ) tests.

RESULTS

The healthy volunteers showed a greater preference for green but a lesser one for brown compared to the patients with schizophrenia. Patients scored higher than the healthy volunteers on the ZKPQ Neuroticism-Anxiety and Activity scales. Moreover, in patients, black preference ranking was associated with the Neuroticism-Anxiety, whereas pink and orange preferences were negatively associated with Activity; white preference correlated negatively with Sociability.

CONCLUSIONS

Patients with schizophrenia preferred green less but brown more, and displayed their personality correlates of these color preferences. These findings are suggesting that patients with schizophrenia should be encouraged to be more exposed to bright colors such as green and white, and less to dark colors such as black, during therapy and rehabilitation sessions.

Sensation/novelty seeking in psychotic disorders: A review of the literature

The evaluation of personality traits is important for the better understanding of the person suffering from psychosis and for treatment individualization. However literature on patients’ personality and character in such disorders is limited. The aim of this review was to summarize the literature on sensation/novelty seeking (SNS), a trait which is biologically based and highly heritable and is associated with dopamine activity, and refers to a person’s tendency to seek varied, novel, complex, and intense sensations and experiences. A total of 38 studies were included in this review, involving 2808 patients and 2039 healthy controls. There is consistent evidence that this trait is independently associated with alcohol and substance abuse in patients with schizophrenia and related disorders. The estimation of SNS would help clinicians to identify patients at risk for abuse. There is also some evidence that higher SNS levels may relate to medication non-adherence and seem to increase the risk of patients’ aggressive and violent behavior, but studies are scarce. SNS was found not to be related to suicidality, whereas in the fields of patients’ quality of life and psychopathology results are contradictory, but most studies show no possible association. Several studies suggest that SNS is lower in psychotic patients compared to controls, whereas most yield no differences. The evidence for this trait as a potential endophenotype of schizophrenia is weak. SNS may be implicated in psychotic disorders’ course and prognosis in several ways and should be always inquired for. This trait can be reliably measured with the use of easily applicable self-rated instruments, and patients’ accounts could inform clinicians when planning management and delivering individualized treatment.

Paranoid personality disorder in the United States: the role of race, illicit drug use, and income

Differential rates of schizophrenia and paranoia symptoms have been found for Black and White individuals. Paranoid personality disorder shares symptoms with schizophrenia, yet has received minimal attention with regard to potential racial differences. In a sample consisting of 180 substance use disorder treatment-seeking individuals, the association between the diagnosis of paranoid personality disorder and the variables of race, cannabis use disorder, and income were examined. Results extended previous findings to paranoid personality disorder, supporting the hypothesis that Black individuals would be diagnosed with higher rates of paranoid personality disorder. Cannabis use disorder status and income did not predict paranoid personality disorder diagnoses.

Temperament and character in remitted and symptomatic patients with schizophrenia: modulation by the COMT Val158Met genotype

While research on remission in schizophrenia has gained attention, personality characteristics associated with remission in schizophrenia have been under-studied. A functional valine-to-methionine (Val158Met) polymorphism in the catechol-O-methyltransferase (COMT) gene is shown to modify clinical presentation of schizophrenia despite weak or no association with the disorder itself. Studies also report that this polymorphism can affect personality traits. We aimed to examine personality traits of remitted patients with schizophrenia as compared to symptomatic patients and healthy controls and to investigate whether the COMT Val158Met polymorphism influences their personality. Scores on the Temperament and Character Inventory were compared between 34 remitted outpatients with schizophrenia, age- and sex-matched 72 symptomatic outpatients with schizophrenia, and matched 247 healthy individuals. The effect of COMT Val158Met polymorphism on personality was examined in each group. The analysis of covariance, controlling for confounding variables, revealed that compared to healthy controls, symptomatic patients exhibited a pervasively altered personality profile whereas remitted patients showed alterations in more limited personality dimensions and demonstrated normal levels of novelty-seeking, reward dependence and cooperativeness. The two-way analysis of covariance, with genotype and sex as between-subject factors and confounders as covariates, revealed that Met carriers demonstrated significantly lower reward dependence and cooperativeness than Val homozygotes in symptomatic patients; while no significant genotype effect was found in remitted patients or in healthy individuals. These findings indicate that remitted patients with schizophrenia have a relatively adaptive personality profile compared to symptomatic patients. The COMT Val158Met polymorphism might have a modulating effect on the relationship between personality and remission.

Openness to experience, intellect, schizotypal personality disorder, and psychoticism: resolving the controversy

Section III of DSM-5 includes an alternative model for personality disorders comprising five higher-order pathological personality traits, four of which resemble domains from the Big Five/Five-Factor Model of Personality (FFM). There has, however, been considerable debate regarding the association of FFM Openness-to-Experience/Intellect (OE/I) with DSM-5 Psychoticism and Schizotypal Personality Disorder (STPD). The authors identify several limitations in the literature, including inattention to (a) differences in the conceptualization of OE/I in the questionnaire and lexical traditions and (b) the symptom heterogeneity of STPD. They then address these limitations in two large patient samples. The results suggest that OE/I per se is weakly associated with Psychoticism and STPD symptoms. However, unique variance specific to the different conceptualizations of OE/I demonstrates much stronger associations, often in opposing directions. These results clarify the debate and the seemingly discrepant views that OE/I is unrelated to Psychoticism and contains variance relevant to Psychoticism.

Hedonic capacity and schizotypy: evidence for the criterion validity of the ACIPS

The association between trait hedonic capacity and schizotypal personality traits was examined in a two studies of independent nonclinical samples. In both investigations, hedonic capacity was measured using the 17-item Anticipatory and Consummatory Interpersonal Pleasure Scale (ACIPS). In Study One, the young adults' (n=1345) ACIPS scores were inversely associated with their scores on the Schizotypal Personality Questionnaire (SPQ). In Study Two, two groups of individuals identified on the basis of their scores on the Schizotypal Personality Questionnaire Brief-Revised (SPQ-BR) were compared in terms of their ACIPS responses and response patterns. Our results indicate that the high schizotypal subjects (n =38) and the low schizotypal subjects (n=37) differed significantly in terms of their mean ACIPS scores, but not in terms of their mean reaction times. Despite differences in study design, both investigations indicated an association between the No Close Friends subscale of the SPQ and the ACIPS total score. These findings are considered in the context of other extant studies of schizotypal traits and the role of anhedonia in schizotypy. Overall, the findings provide further evidence for the criterion validity of the ACIPS.

Cognitive task performance and symptoms contribute to personality abnormalities in first hospitalized schizophrenia

Chronic schizophrenia patients have personality abnormalities and cognitive deficits that are associated with poor clinical, social, and vocational outcomes. Very few studies have examined relationships between personality and cognitive function, and chronic illness effects may have confounded those studies. In this study personality traits in clinically stable first episode schizophrenia patients (21M, 9F) and psychiatrically healthy controls (38M, 24F) were measured with the NEO-FFI, a self-report measure of neuroticism, extraversion, openness, agreeableness, and conscientiousness. All subjects completed the Information, Digit Span, Vocabulary, and Digit Symbol subtests of the Wechsler Adult Intelligence Scale; and Trails A and B. Standard statistical techniques were used to quantify relationships between personality and symptom levels and/or task performance, and relative contributions of diagnosis and task performance to personality variance. Patients showed elevated mean neuroticism and openness, and reduced mean extraversion, agreeableness and conscientiousness. Task performance and negative symptoms contributed significantly and uniquely to most personality dimensions in patients. Task performance accounted for significant amounts of personality variance even after accounting for diagnosis, and it also contributed to personality variance in controls. These results suggest that cognitive deficits and negative symptoms contribute to consistently observed personality abnormalities in this disorder, and that the contribution of neuropsychological performance to personality variance may be independent of diagnostic classification. Personality abnormalities in schizophrenia may stem from the neurocognitive deficits associated with this disorder, and add to their adverse effects on social and vocational functioning.