Polygenic risk for depression predicting temperament trajectories over 15 years - A general population study.

BACKGROUND: A great number of case-control and population-based studies have shown that depression patients differ from healthy controls in their temperament traits. We investigated whether polygenic risk for depression predicts trajectories of temperament traits from early adulthood to middle age. METHODS: Participants came from the population-based Young Finns Study (n = 2212). The calculation for Polygenic risk for depression (PRS) was based on the most recent genome-wide association study. Temperament traits of Harm Avoidance, Novelty Seeking, Reward Dependence, and Persistence were assessed with the Temperament and Character Inventory in 1997, 2001, 2007, and 2012 (participants being 24-50-year-olds). As covariates, we used depressive symptoms as assessed by a modified version of the Beck Depression Inventory, psychosocial family environment from parent-filled questionnaires, and socioeconomic factors from adulthood. RESULTS: High PRS predicted higher Persistence from early adulthood to middle age (p = 0.003) when controlling for depressive symptoms, psychosocial family environment, and socioeconomic factors. PRS did not predict trajectories of Novelty Seeking (p = 0.063-0.416 in different models) or Reward Dependence (p = 0.531-0.736). The results remained unaffected when participants with diagnosed affective disorders were excluded. Additionally, we found an interaction between PRS and depressive symptoms when predicting the Harm Avoidance subscale Anticipatory Worry, indicating that the association of Anticipatory Worry with depressive symptoms is stronger in individuals with higher (vs. lower) PRS. LIMITATIONS: There was some attrition due to the long follow-up. CONCLUSIONS: High polygenic risk for major depression may predict differences in temperament trajectories among those who have not developed any severe affective disorders.

Three joint temperament-character configurations account for learning, personality and well-being: normative demographic findings in a representative national population.

Introduction: A common practice in research and clinical practice is to use data considered representative of a target population to compare and understand the personality characteristics of specific groups or specific individuals. To this end, numerous studies have presented normative data for the temperament and character traits outlined in Cloninger's psychobiological model of personality. However, recent genomic evidence demonstrates that human personality is organized as a complex hierarchy that ascends beyond the individual traits to multi-trait profiles that regulate emotional reactivity (temperament profiles) or goals and values (character profiles), and then to three phenotypic networks, which integrate temperament profiles and character profiles, that regulate learning. Given this recent understanding, our aim was to provide a novel and more comprehensive description of personality features at a societal level (using a stratified sample representative of the Portuguese population) by considering personality at its higher levels of complexity. Methods: Toward this goal, a stratified sample of 2,443 Portuguese adults responded to the Revised Temperament and Character Inventory (TCI-R). Results: We summarize the prevalence of (a) temperament profiles, (b) character profiles, and (c) integrated temperament-character networks within the whole sample, as well as for men vs. women and different age groups separately. Independent of age and education, women were more likely to be capable of resourceful productivity and helpful cooperation combined with being more intuitive, meditative and creative than men. Independent of age and gender, individuals with a degree were also more likely to present these biopsychosocial features. We also found that the organized character profile was most typical of adults in their 40s. Finally, the distribution of personality profiles across age differed as a function of gender: for men the oldest individuals had the most coherent personalities while high personality integration was most prevalent for women in their 30s. Discussion: These results have strong implications for research and intervention. In particular, these results are relevant for understanding the epidemiology of interactions between personality, mental health and well-being, including their expressions in a national population as a function of demographic characteristics.

The relationship of trait-like compassion with epigenetic aging: The population-based prospective Young Finns Study.

Introduction: Helping others within and beyond the family has been related to living a healthy and long life. Compassion is a prosocial personality trait characterized by concern for another person who is suffering and the motivation to help. The current study examines whether epigenetic aging is a potential biological mechanism that explains the link between prosociality and longevity. Methods: We used data from the Young Finns Study that follows six birth-cohorts from age 3-18 to 19-49. Trait-like compassion for others was measured with the Temperament and Character Inventory in the years 1997 and 2001. Epigenetic age acceleration and telomere length were measured with five DNA methylation (DNAm) indicators (DNAmAgeHorvath, IEAA_Hannum, EEAA_Hannum, DNAmPhenoAge, and DNAmTL) based on blood drawn in 2011. We controlled for sex, socioeconomic status in childhood and adulthood, and body-mass index. Results and discussion: An association between higher compassion in 1997 and a less accelerated DNAmPhenoAge, which builds on previous work on phenotypic aging, approached statistical significance in a sex-adjusted model (n = 1,030; b = -0.34; p = 0.050). Compassion in 1997 predicted less accelerated epigenetic aging over and above the control variables (n = 843; b = -0.47; p = 0.016). There was no relationship between compassion in 2001 (n = 1108/910) and any of the other four studied epigenetic aging indicators. High compassion for others might indeed influence whether an individual's biological age is lower than their chronological age. The conducted robustness checks partially support this conclusion, yet cannot rule out that there might be a broader prosocial trait behind the findings. The observed associations are interesting but should be interpreted as weak requiring replication.

Temperament and character in an Australian sample: examining cross-sectional associations of personality with age, sex, and satisfaction with life.

Objective: Personality can influence how we interpret and react to our day-to-day life circumstances. Temperament and character are the primary dimensions of personality, and both are influenced genetically. Temperament represents our emotional core, while character reflects our goals and values as we develop through life. Research shows that where people live, their social, economic, and physical environment can influence attitudes and behaviors, and these have links to variations in personality traits. There are few studies that focus on Australian personality as temperament and character. Using an Australian general population sample, we examined the psychometric properties of the Temperament and Character Inventory (TCIR140) and investigated the associations between TCIR140 traits with both sociodemographic variables and measures of well-being. In addition, we investigated differences in temperament and character between our Australian general population sample and published results of similar studies from other countries. Methods: Australians (N = 1,510) completed the Temperament and Character Inventory (TCIR-140), the Positive and Negative Affect Scale and the Satisfaction with Life Scale. Cronbach's alpha and confirmatory factor analysis (CFA) examined the TCIR-140 psychometrics. Correlation analyzes, independent sample t-tests and ANOVA with post-hoc comparisons analyzed the sample. Results: Cronbach's alphas were high, ranging from α = 0.78-0.92, and the CFA confirmed two constructs of temperament and character. Females were higher in Harm Avoidance (p < 0.001), Reward Dependence (p < 0.001), and Cooperativeness (p < 0.001) compared to males, who were higher in Self-Directedness (p < 0.001). Age groups showed significant differences among all temperament and character traits (p < 0.001) except for Reward Dependence (p = 0.690). Young adults had the least resilient personality profile and poorest measures of well-being. Correlations with measures of temperament and character, well-being and affect were all in the expected direction. Conclusions: Temperament and character are related to indicators of wellbeing and differs by age and sex. This Australian sample demonstrate a temperament that is high in Persistence and a character high in Self-Directedness and Cooperativeness with an overall postive affect and a general satisfaction with life. In comparison to other countries, Australians in this sample differ in levels of several traits, demonstrating a cautious and independent temperament with a character that is cooperative, industrious, and self-reliant. Young-adults in comparison to older groups have a temperament and character profile that is prone to negative emotions and a lower satisfaction with life.

Temperament & Character account for brain functional connectivity at rest: A diathesis-stress model of functional dysregulation in psychosis.

The human brain's resting-state functional connectivity (rsFC) provides stable trait-like measures of differences in the perceptual, cognitive, emotional, and social functioning of individuals. The rsFC of the prefrontal cortex is hypothesized to mediate a person's rational self-government, as is also measured by personality, so we tested whether its connectivity networks account for vulnerability to psychosis and related personality configurations. Young adults were recruited as outpatients or controls from the same communities around psychiatric clinics. Healthy controls (n = 30) and clinically stable outpatients with bipolar disorder (n = 35) or schizophrenia (n = 27) were diagnosed by structured interviews, and then were assessed with standardized protocols of the Human Connectome Project. Data-driven clustering identified five groups of patients with distinct patterns of rsFC regardless of diagnosis. These groups were distinguished by rsFC networks that regulate specific biopsychosocial aspects of psychosis: sensory hypersensitivity, negative emotional balance, impaired attentional control, avolition, and social mistrust. The rsFc group differences were validated by independent measures of white matter microstructure, personality, and clinical features not used to identify the subjects. We confirmed that each connectivity group was organized by differential collaborative interactions among six prefrontal and eight other automatically-coactivated networks. The temperament and character traits of the members of these groups strongly accounted for the differences in rsFC between groups, indicating that configurations of rsFC are internal representations of personality organization. These representations involve weakly self-regulated emotional drives of fear, irrational desire, and mistrust, which predispose to psychopathology. However, stable outpatients with different diagnoses (bipolar or schizophrenic psychoses) were highly similar in rsFC and personality. This supports a diathesis-stress model in which different complex adaptive systems regulate predisposition (which is similar in stable outpatients despite diagnosis) and stress-induced clinical dysfunction (which differs by diagnosis).

Disentangling the personality pathways to well-being.

Recent genomic, psychological, and developmental research shows that human personality is organized as a complex hierarchy that ascends from individual traits in many specific situations to multi-trait profiles in two domains that regulate emotional reactivity (temperament) or goals and values (character), and finally to three integrated temperament-character networks that regulate learning to maintain well-being in changing conditions. We carried out person-centered analyses of the components of subjective well-being (positive affect, negative affect, and life satisfaction) to personality in both adolescents (N = 1739) and adults (N = 897). Personality was considered at each level of its organization (trait, temperament or character profiles, and joint temperament-character networks). We show for the first time that negative affect and life satisfaction are dependent on the personality network for intentional self-control, whereas positive affect is dependent on the personality network for self-awareness that underlies the human capacities for healthy longevity, creativity, and prosocial values.

Uncovering the complex genetic architecture of human plasma lipidome using machine learning methods.

Genetic architecture of plasma lipidome provides insights into regulation of lipid metabolism and related diseases. We applied an unsupervised machine learning method, PGMRA, to discover phenotype-genotype many-to-many relations between genotype and plasma lipidome (phenotype) in order to identify the genetic architecture of plasma lipidome profiled from 1,426 Finnish individuals aged 30-45 years. PGMRA involves biclustering genotype and lipidome data independently followed by their inter-domain integration based on hypergeometric tests of the number of shared individuals. Pathway enrichment analysis was performed on the SNP sets to identify their associated biological processes. We identified 93 statistically significant (hypergeometric p-value < 0.01) lipidome-genotype relations. Genotype biclusters in these 93 relations contained 5977 SNPs across 3164 genes. Twenty nine of the 93 relations contained genotype biclusters with more than 50% unique SNPs and participants, thus representing most distinct subgroups. We identified 30 significantly enriched biological processes among the SNPs involved in 21 of these 29 most distinct genotype-lipidome subgroups through which the identified genetic variants can influence and regulate plasma lipid related metabolism and profiles. This study identified 29 distinct genotype-lipidome subgroups in the studied Finnish population that may have distinct disease trajectories and therefore could be useful in precision medicine research.

Coherence of character and temperament drives personality change toward well being in person-centered therapy.

PURPOSE OF REVIEW: People and communities around the world face many crises, including increasing burdens from disease, psychopathology, burn-out, social distrust, and acts of hate and terrorism. Personality disorder is arguably both a root cause and a consequence of these problems, creating a vicious cycle of suffering caused by fears, immoderate desires, and social distrust that are inconsistent with rational goals and prosocial values. Fortunately, recent advances in understanding the biopsychosocial basis and dynamics of development in personality and its disorders offer insights to address these problems in effective person-centered ways. RECENT FINDINGS: Fundamental advances have been made recently in the understanding of the psychobiology and sociology of personality in relationship to health, and in basic mechanisms of personality change as a complex process of learning and memory. Promotion of self-awareness and intentional self-control releases a strong tendency for people to seek coherence of their emotions and habits with what gives their life meaning and value. SUMMARY: People have a strong drive to cultivate personalities in which their emotions and habits are reliably in accord with reasonable goals and prosocial values. Person-centered therapeutics provide practical ways to promote a virtuous cycle of increasing well being for individuals and their communities and habitats.

Differences in subjective well-being between individuals with distinct Joint Personality (temperament-character) networks in a Bulgarian sample.

Background: Personality is the major predictor of people's subjective well-being (i.e., positive affect, negative affect, and life satisfaction). Recent research in countries with high-income and strong self-transcendent values shows that well-being depends on multidimensional configurations of temperament and character traits (i.e., Joint Personality Networks) that regulate the way people learn to adapt their habits to be in accord with their goals and values, rather than individual traits. To evaluate the prevalence and the associations of different Joint Personality (temperament-character) Networks with well-being in a low-income country with weak self-transcendent values, we tested their association in Bulgarian adults, a population known to have strong secular-rationalist values but weak self-transcendent values. Method: The sample consisted of 443 individuals from Bulgaria (68.70% females) with a mean age of 34 years (SD = 15.05). Participants self-reported personality (Temperament and Character Inventory), affect (Positive Affect Negative Affect Schedule), and life satisfaction (Satisfaction with Life Scale). The personality scores were used for profiling through latent profile analysis and latent class analysis based on temperament configurations (i.e., Temperament Profiles) of high/low scores of Novelty Seeking (N/n), Harm Avoidance (H/h), Reward Dependence (R/r), and Persistence (P/s); and character configurations (i.e., Character Profiles) of high/low scores of Self-Directedness (S/s), Cooperativeness (C/c), and Self-Transcendence (T/t). Results: We found two Temperament Profiles and two Character Profiles that clustered into two distinctive Joint Personality Networks. All individuals in Joint Personality Network 1 had a Reliable (nhRP) Temperament Profile in combination with an Organized (SCt) Character Profile (i.e., a stable temperament and a healthy character configuration). About 71.9% in Joint Personality Network 2 had an Apathetic (sct) Character Profile in combination with Methodical (nHrp) or Reliable (nhRP) Temperament Profiles, while 28.1% had a Methodical (nHrp) Temperament Profile in combination with an Organized (SCt) Character Profile. Few people with high self-expressive values (i.e., high in all three character traits; SCT) were found. Individuals with a Joint Personality Network 1 with strong secular-rationalist values reported higher levels of positive affect and life satisfaction (p < .001), while individuals with a Joint Personality Network 2 reported higher levels of negative affect (p < .001). Conclusions: Although a stable temperament and a healthy character were separately important for well-being, it was clear that it was the interaction between such temperament and character configuration that yielded greater levels of subjective well-being. Nevertheless, future research needs to investigate this interaction further to evaluate other cultures with variable configurations of personality traits and values.

Does social intolerance vary according to cognitive styles, genetic cognitive capacity, or education?

BACKGROUND: Low education, low cognitive abilities, and certain cognitive styles are suggested to predispose to social intolerance and prejudices. Evidence is, however, restricted by comparatively small samples, neglect of confounding variables and genetic factors, and a narrow focus on a single sort of prejudice. We investigated the relationships of education, polygenic cognitive potential, cognitive performance, and cognitive styles with social intolerance in adulthood over a 15-year follow-up. METHODS: We used data from the prospective population-based Young Finns Study (n = 960-1679). Social intolerance was evaluated with the Social Intolerance Scale in 1997, 2001, and 2011; cognitive performance with the Cambridge Neuropsychological Test Automated Battery in 2011; cognitive styles in 1997; and socioeconomic factors in 1980 (childhood) and 2011 (adulthood); and polygenic cognitive potential was calculated based on genome-wide association studies. RESULTS: We found that nonrational thinking, polygenic cognitive potential, cognitive performance, or socioeconomic factors were not related to social intolerance. Regarding cognitive styles, low flexibility (B = -0.759, p < .001), high perseverance (B = 1.245, p < .001), and low persistence (B = -0.329, p < .001) predicted higher social intolerance consistently in the analyses. DISCUSSION: When developing prejudice-reduction interventions, it should be considered that educational level or cognitive performance may not be crucial for development of social intolerance. Adopting certain cognitive styles may play more important roles in development of social intolerance.

Dissociation and psychopathology in Kenyan survivors of a terrorist bombing.

BACKGROUND: Dissociation is a serious psychological condition that is characterized as a pathological outcome of trauma-related experience. Thus, dissociation could be expected to develop in survivors of disaster trauma and to be associated with trauma exposure and psychopathology. METHODS: A sample of 278 disaster-affected Kenyans was assessed 8 to 10 months after the 1998 terrorist bombing of the US Embassy in Nairobi for a study of trauma-related psychopathology and dissociation in the context of personality and culture. Instruments of assessment were the Diagnostic Interview Schedule, the Dissociative Experiences Scale, and the Temperament and Character Inventory. RESULTS: Dissociation appeared to represent a largely nonpathological response to the disaster experience that reflected personality variables and a cultural context. CONCLUSIONS: These findings suggest that dissociation encountered in disaster-exposed groups in this cultural setting does not necessarily represent psychopathology, but attention to dissociative responses might help clinicians identify and provide interventions for individuals experiencing distressing intrusive and hyperarousal symptoms.

The relationship between temperament, polygenic score for intelligence and cognition: A population-based study of middle-aged adults.

We investigated whether temperament modifies an association between polygenic intelligence potential and cognitive test performance in midlife. The participants (n = 1647, born between 1962 and 1977) were derived from the Young Finns Study. Temperament was assessed with Temperament and Character Inventory over a 15-year follow-up (1997, 2001, 2007, 2012). Polygenic intelligence potential was assessed with a polygenic score for intelligence. Cognitive performance (visual memory, reaction time, sustained attention, spatial working memory) was assessed with CANTAB in midlife. The PGSI was significantly associated with the overall cognitive performance and performance in visual memory, sustained attention and working memory tests but not reaction time test. Temperament did not correlate with polygenic score for intelligence and did not modify an association between the polygenic score and cognitive performance, either. High persistence was associated with higher visual memory (B = 0.092; FDR-adj. p = 0.007) and low harm avoidance with higher overall cognitive performance, specifically better reaction time (B = -0.102; FDR-adj; p = 0.007). The subscales of harm avoidance had different associations with cognitive performance: higher "anticipatory worry," higher "fatigability," and lower "shyness with strangers" were associated with lower cognitive performance, while the role of "fear of uncertainty" was subtest-related. In conclusion, temperament does not help or hinder one from realizing their genetic potential for intelligence. The overall modest relationships between temperament and cognitive performance advise caution if utilizing temperament-related information e.g. in working-life recruitments. Cognitive abilities may be influenced by temperament variables, such as the drive for achievement and anxiety about test performance, but they involve distinct systems of learning and memory.

Personality and Psychiatric Disorders among Employees of New York City Workplaces Affected by the 9/11 Attacks on the World Trade Center.

OBJECTIVE: Personality is associated with psychopathology after disasters, but its association with the portion of postdisaster psychopathology that is incident remains unclear. It is also unclear whether any particular attributes of personality are associated with resistance to the persistence or recurrence of preexisting psychopathology after disasters. This exploratory study of employees of workplaces affected by the September 11, 2001, attacks on the World Trade Center in New York City examined the specific relationships of personality variables (specifically, novelty seeking, harm avoidance, reward dependence, persistence, self-directedness, cooperativeness, and self-transcendence) to incident postdisaster psychiatric disorders and resistance to the persistence/recurrence of preexisting psychiatric disorders after the disaster. METHODS: Approximately 3 years after the 9/11 attacks, 379 employees were recruited from 8 selected affected workplaces (3 in the World Trade Center towers, 5 at varied distances in the geographic area). Lifetime predisaster and postdisaster psychiatric disorders were assessed retrospectively with the Diagnostic Interview Schedule for DSM-IV, disaster experience details were collected with the Disaster Supplement, and personality was assessed with the Temperament and Character Inventory. RESULTS: Underdeveloped executive functioning (low self-directedness and/or low cooperativeness) was associated with incident postdisaster psychopathology, and components of resilience (low harm avoidance, high self-directedness, and high persistence) were associated with postdisaster resistance to persistence/recurrence of preexisting psychiatric illness. CONCLUSIONS: Personality is related to both incident and persistent/recurrent portions of postdisaster psychopathology, not clearly distinguished in previous research. Personality variables related to executive functioning and resilience may aid in assessing risk and developing treatments to prevent disaster-related psychopathology.

Bidirectional pathways between psychosocial risk factors and paranoid ideation in a general nonclinical population.

We investigated (a) whether psychosocial factors (experienced stress, anticipatory worry, social detachment, sleeping disturbances, alcohol use) predict the course of paranoid ideation between the ages of 24 to 50 years and (b) whether the predictive relationships are more likely to proceed from the psychosocial factors to paranoid ideation, or vice versa. The participants (N = 1534-1553) came from the population-based Young Finns study. Paranoid ideation and psychosocial factors were assessed by reliable self-report questionnaires in 2001, 2007, and 2011/2012. The data were analyzed using growth curve and structural equation models. High experienced stress, anticipatory worry, social detachment, frequent sleeping disturbances, and frequent alcohol use predicted more paranoid ideation. More risk factors predicted increasing paranoid ideation. There were bidirectional predictive relationships of paranoid ideation with experienced stress, anticipatory worry, social detachment, and sleeping disturbances. The link between alcohol use and paranoid ideation was only correlative. In conclusion, paranoid ideation increases by reciprocal interactions with stress, worry, social detachment, and sleeping disturbances. The findings support the threat-anticipation model of paranoid ideation, providing important implications for treatment of paranoia.

Personality Networks and Emotional and Behavioral Problems: Integrating Temperament and Character Using Latent Profile and Latent Class Analyses.

Recent research indicates that adaptive functioning and well-being depends on the integration of three dissociable systems of learning and memory that regulate associative conditioning, intentionality and self-awareness. Our study objective was to describe how different integrated configurations of these systems (i.e. different expressions of personality) relate to the presence of internalizing, externalizing and total problems. In total, 699 adolescents completed the JTCI and Achenbach's YSR. Latent profile analyses revealed two temperament profiles and six character profiles. Adolescents with a steady temperament, and those with healthy characters, were significantly less likely to present clinical levels of problems. The integration of a steady temperament and healthy character profiles in a Mature-Steady joint temperament-character network was also associated with significantly less clinical problems. In sum, our person-centered study indicates that adaptive expressions of associative conditioning, intentionality, and self-awareness (i.e. integrated personalities) are critical for mental health.

Student engagement with school and personality: a biopsychosocial and person-centred approach.

BACKGROUND: Engagement with school is a key predictor of students' academic outcomes, yet little is known about its association with personality. No research has considered this association using Cloninger's biopsychosocial model of personality. This model may be particularly informative because it posits the structure of human personality corresponds to three systems of human learning and memory that regulate associative conditioning, intentionality, and self-awareness, all of which are relevant for understanding engagement. AIMS: To test for defined personality phenotypes and describe how they relate to student engagement. SAMPLE: 469 adolescents (54.2% female) attending the eighth (Mage  = 13.2, SD = .57) or 11th (Mage  = 16.5, SD = .84) grades. METHODS: Students completed self-report measures of personality and engagement. We used mixture models to identify latent classes defined by common (1) temperament profiles, (2) character profiles, and (3) joint temperament-character networks, and then tested how these classes differed in engagement. RESULTS: Latent class analysis revealed three distinct joint temperament-character networks: Emotional-Unreliable (emotionally reactive, low self-control, and low creativity), Organized-Reliable (self-control but not creative), and Creative-Reliable (highly creative and prosocial). These networks differed significantly in engagement, with the emotional-unreliable network linked to lower engagement. However, the magnitudes of these differences across engagement dimensions did not appear to be uniform. CONCLUSIONS: Different integrated configurations of the biopsychosocial systems for associative conditioning, intentionality, and self-awareness (differences in personality) underlie student engagement. Our results offer a fine-grained understanding of engagement dimensions in terms of their underlying personality networks, with implications for educational policies and practices.

Three genetic-environmental networks for human personality.

Phylogenetic, developmental, and brain-imaging studies suggest that human personality is the integrated expression of three major systems of learning and memory that regulate (1) associative conditioning, (2) intentionality, and (3) self-awareness. We have uncovered largely disjoint sets of genes regulating these dissociable learning processes in different clusters of people with (1) unregulated temperament profiles (i.e., associatively conditioned habits and emotional reactivity), (2) organized character profiles (i.e., intentional self-control of emotional conflicts and goals), and (3) creative character profiles (i.e., self-aware appraisal of values and theories), respectively. However, little is known about how these temperament and character components of personality are jointly organized and develop in an integrated manner. In three large independent genome-wide association studies from Finland, Germany, and Korea, we used a data-driven machine learning method to uncover joint phenotypic networks of temperament and character and also the genetic networks with which they are associated. We found three clusters of similar numbers of people with distinct combinations of temperament and character profiles. Their associated genetic and environmental networks were largely disjoint, and differentially related to distinct forms of learning and memory. Of the 972 genes that mapped to the three phenotypic networks, 72% were unique to a single network. The findings in the Finnish discovery sample were blindly and independently replicated in samples of Germans and Koreans. We conclude that temperament and character are integrated within three disjoint networks that regulate healthy longevity and dissociable systems of learning and memory by nearly disjoint sets of genetic and environmental influences.

Effects of personality on the developmental trajectories of academic burnout among Korean medical students.

BACKGROUND: Medical students have a high risk of burnout from tremendous academic stress, and previous cross-sectional studies have explained this risk from the personality perspective. However, the relationship between complex personality profiles and developmental trajectory of burnout has not been delineated yet. METHODS: The longitudinal changes in burnout were measured by the Maslach Burnout Inventory-Student Survey (MBI-SS) at baseline (1st week), mid-term (9th week), and end-term (17th week), and personality was examined at baseline using the Temperament and Character Inventory (TCI). Latent trajectory groups based on the MBI-SS total scores were extracted using the General Growth Mixture Model (GGMM), and significant differences in personality profiles among the latent groups were identified using profile analysis and Analysis of Variance. RESULTS: Three burnout trajectory groups of high-increasing (HI), moderate-increasing (MI), and low-stable (LS) were identified, and these groups had significantly different TCI subscale profiles. The HI group had the highest score in Harm-Avoidance (HA) and lowest score in Self-Directedness (SD), and the MI group had a higher score in HA and lower scores in SD and Cooperativeness (CO) when compared to the LS group with the lowest score in HA and highest scores in SD and CO. CONCLUSION: The current study showed that the HA, SD, and CO subscales of the TCI might explain the longitudinal development of academic burnout in medical students. Prevention of burnout and promotion of well-being in medical education concerning personality are discussed.

Personality Traits as Markers of Psychosis Risk in Kenya: Assessment of Temperament and Character.

Specific personality traits have been proposed as a schizophrenia-related endophenotype and confirmed in siblings at risk for psychosis. The relationship of temperament and character with psychosis has not been previously investigated in Africa. The study was conducted in Kenya, and involved participants at clinical high-risk (CHR) for psychosis (n = 268) and controls (n = 251), aged 15-25 years. CHR status was estimated using the Structured Interview of Psychosis-Risk Syndromes (SIPS) and the Washington Early Psychosis Center Affectivity and Psychosis (WERCAP) Screen. Student's t-tests were used to assess group differences on the Temperament and Character Inventory (TCI). Neurocognitive functioning, stress severity, and substance use were correlated with the TCI, correcting for psychosis severity. CHR participants were more impulsive (ie, higher novelty seeking [NS]) and asocial (ie, lower reward dependence) than controls. They were also more schizotypal (ie, high self-transcendence [ST] and lower self-directedness [SD] and cooperativeness [CO] than controls). CO was related to logical reasoning, abstraction, and verbal memory. Stress severity correlated with high HA and schizotypal character traits. Lifetime tobacco use was related to NS, and lifetime marijuana use to high NS, low SD and high ST. Temperament and character of Kenyan CHR youth is similar to that observed in schizophrenia. Psychosis risk in Kenya is associated with impulsive, asocial, and schizotypal traits. CHR adolescents and young adults with schizophrenia-specific personality traits may be most at risk for developing a psychotic disorder and to require early intervention to improve outcomes.