The genetic and environmental structure of the character sub-scales of the temperament and character inventory in adolescence

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).

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.

The genetic and environmental origins of emotional and cognitive empathy: Review and meta-analyses of twin studies

Empathy is considered a cornerstone of human social experience, and as such has been widely investigated from psychological and neuroscientific approaches. To better understand the factors influencing individual differences in empathy, we reviewed and meta-analyzed the behavioral genetic literature of emotional empathy- sharing others' emotions (k=13), and cognitive empathy- understanding others' emotions (k = 15), as manifested in twin studies. Results showed that emotional empathy is more heritable, 48.3 % [41.3 %-50.6 %], than cognitive empathy, 26.9 % [18.1 %-35.8 %]. Moreover, cognitive empathy as examined by performance tests was affected by the environment shared by family members, 11.9 % [2.6 %-21.0 %], suggesting that emotional understanding is influenced, to some degree, by environmental factors that have similar effects on family members beyond their genetic relatedness. The effects of participants' age and the method used to asses empathy on the etiology of empathy were also examined. These findings have implications for understanding how individual differences in empathy are formed. After discussing these implications, we suggest theoretical and methodological future research directions that could potentially elucidate the relations between genes, brain, and empathy.

Did I Inherit My Moral Compass? Examining Socialization and Evocative Mechanisms for Virtuous Character Development

Virtuous character development in children is correlated with parenting behavior, but the role of genetic influences in this association has not been examined. Using a longitudinal twin/sibling study (N = 720; Time 1 (T1) Mage = 12-14 years, Time 3 (T3) Mage = 25-27 years), the current report examines associations among parental negativity/positivity and offspring responsibility during adolescence, and subsequent young adult conscientiousness. Findings indicate that associations among parental negativity and offspring virtuous character during adolescence and young adulthood are due primarily to heritable influences. In contrast, the association between concurrent parental positivity and adolescent responsibility was due primarily to heritable and shared environmental influences. These findings underscore the contributions of heritable influences to the associations between parenting and virtuous character that have previously been assumed to be only environmentally influenced, emphasizing the complexity of mechanisms involved in the development of virtuous character.

The role of anxious temperament in patients with allergic rhinitis

OBJECTIVES

To evaluate the ‎depressive and anxiety levels in allergic rhinitis (AR) and to investigate the relationship between ‎depression and anxiety symptoms and depressive and anxious temperament features. Methods: The study design is cross-sectional. The study was conducted between January 2017 and January  2018. Patients (n=101)  diagnosed with  AR and healthy controls (n=74) were included in this ‎study. All participants were assessed with the Beck Depression Inventory (BDI), Beck Anxiety‎ Inventory (BAI), and TEMPS-A (Temperament Evaluation of Memphis, Pisa, Paris, San Diego ‎Autoquestionaire).‎ Results: The median BAI and BDI scores of the patients were found to be significantly higher than the control group (p=0.016 and p=0.001). In AR patients, ‎the percentage of depressive and anxious temperaments were ‎significantly higher than in the control group (p=0.029). Depressive temperament scores showed strong positive correlation with anxious temperament ‎ and BDI scores and a medium relationship with the BAI (r; p=0.639; p less than 0.001, p=0.671; p less than 0.001, and p=0.495; p less than 0.001, respectively). Participants with anxious ‎temperament had 6.3-times (95% CI: 1.3-28.3) the risk for developing AR.‎ Conclusion: Screening of temperament traits in AR patients may allow prediction of future ‎depression and anxiety symptoms. These temperament traits may be mediators of depression ‎and anxiety in AR patients. Depressive and anxious temperament traits may contribute to both ‎depression and allergy.