Comprehensive meta-analysis of associations between temperament and character traits in Cloninger’s psychobiological theory and mental disorders

Objective To explore the relationship between temperament and character traits in Cloninger’s psychobiological theory and mental disorders. Methods: A systematic literature search was conducted of five international databases for all articles published in English between January 1990 and April 2019 (PROSPERO-CRD42019133214). Owing to heterogeneity, pooled estimates of correlations for personality disorders and standardized mean differences for case–control studies related to other mental disorders were calculated using the random-effects method. Results The pooled effect sizes obtained from 149 studies showed that high harm avoidance (related to 22/24 diagnostic categories), low self-directedness (21/23), low cooperativeness (17/23), high self-transcendence (14/23), low reward dependence (11/24), high novelty-seeking (10/24), low novelty-seeking (7/24), high persistence (2/23), low persistence (2/23) and high reward dependence (2/24) were related to psychopathology. Conclusions All traits provided unique psychobiological tools for differential diagnosis of mental disorders. However, high harm avoidance and low self-directedness played a canonical role in psychopathology. Despite the study limitations, additional studies are warranted to evaluate the differential diagnoses suggested by the present model.

Personality characteristics and medical impact of stimulant laxative abuse in eating disorder patients—a pilot study

Background Stimulant laxative abuse as a purging behavior can be profound in those with eating disorders. However, the psychopathology leading to stimulant laxative abuse is poorly understood. Furthermore, the medical impact of stimulant laxative abuse has not been studied in this population. Methods Six individuals abusing stimulant laxatives underwent a barium enema to assess for evidence of the cathartic colon syndrome and 29 individuals engaging in any purging behaviors completed the Tri-dimensional Personality Questionnaire-Short Form, Sensitivity to Punishment/Sensitivity to Reward Questionnaire-Short Form, Beck Depression Inventory, and the State Trait Anxiety Inventory questionnaires. Results Three of the six patients completing the barium enema had the radiographic findings consistent with cathartic colon. Individuals engaging in laxative abuse showed higher Novelty Seeking compared to those engaging in other forms of purging, and those engaging in any form of purging behavior showed greater Sensitivity to Punishment compared to Sensitivity to Reward. There was also the presence of greater Harm Avoidance than Reward Dependence in this population. Conclusion There may be different psychopathology that contributes to the abuse of stimulant laxatives than that associated with other forms of purging. Regardless of the driving factor, further research is warranted to discover best therapeutic interventions given the potential to develop the cathartic colon syndrome with ongoing use of stimulant laxatives. Plain English Summary Cathartic colon is a condition whereby the colon, or lower intestine, is converted into an inert tube incapable of propagating fecal matter. It is thought to develop due to over-use of stimulant laxatives. However, it is unclear if this condition truly exists and whether it contributes to the constipation experienced by individuals with eating disorders who have extensive past histories of abusing laxatives. It is also unclear if laxative abuse presents with different medical complications than other forms of purging. The purpose of this study is to determine whether radiographic evidence of cathartic colon can be found in eating disorder patients abusing stimulant laxatives, whether there are different medical complications with laxative abuse versus other forms of purging, and to examine the psychological composition of individuals who engage in severe laxative abuse. Specifically, the authors investigated the interrelationship between Harm Avoidance and Reward Dependence, with emphasis on gaining a better understanding of Reward Dependence by examining both Sensitivity to Reward and Sensitivity to Punishment in patients who engage in severe laxative abuse. Our findings suggest that stimulant laxative abuse may cause the development of cathartic colon changes and that there may be unique psychopathology that contributes to the abuse of stimulant laxatives. Given the higher Novelty Seeking personality-dimension in those abusing laxatives, it is possible that this purging behavior may be considered addiction-like in nature, which would have distinct treatment implications.

Analysis of DRD2 Gene Polymorphism in the Context of Personality Traits in a Group of Athletes

The presented study showed the relationship between dopamine receptor gene polymorphism and personality traits in athletes training in martial arts. Behavioral modulation resulting from a balance of the neurotransmitters dopamine and norepinephrine to inactivation of the dorsolateral prefrontal cortex and dysregulation of various pathways involved in attention and impulse control processes; Methods: The study was conducted among martial arts athletes. The study group included 258 volunteers and 284 controls. The genetic test was performed using the real-time PCR method; psychological tests were performed using standardized TCI questionnaires. All analyses were performed using STATISTICA 13. Results: Interaction between martial arts and DRD2 rs1799732 (manual) G/-(VIC/FAM)-ins/del and RD- Harm avoidance and Reward Dependence scale were demonstrated. In athletes, a lower Reward Dependence scale score was associated with the DRD2 rs1799732 (manual)-/-polymorphism compared to the control group. ; Conclusions: It seems justified to study not only genetic aspects related to brain transmission dopamine in martial arts athletes. In the studied athletes, the features related to reward addiction and harm avoidance are particularly important in connection with the dopaminergic reward system in the brain.

Brainstem glucose metabolism predicts reward dependence scores in treatment-resistant major depression

Background It has been suggested that individual differences in temperament could be involved in the (non-)response to antidepressant (AD) treatment. However, how neurobiological processes such as brain glucose metabolism may relate to personality features in the treatment-resistant depressed (TRD) state remains largely unclear. Methods To examine how brainstem metabolism in the TRD state may predict Cloninger's temperament dimensions Harm Avoidance (HA), Novelty Seeking (NS), and Reward Dependence (RD), we collected 18fluorodeoxyglucose positron emission tomography (18FDG PET) scans in 40 AD-free TRD patients. All participants were assessed with the Temperament and Character Inventory (TCI). We applied a multiple kernel learning (MKL) regression to predict the HA, NS, and RD from brainstem metabolic activity, the origin of respectively serotonergic, dopaminergic, and noradrenergic neurotransmitter (NT) systems. Results The MKL model was able to significantly predict RD but not HA and NS from the brainstem metabolic activity. The MKL pattern regression model identified increased metabolic activity in the pontine nuclei and locus coeruleus, the medial reticular formation, the dorsal/median raphe, and the ventral tegmental area that contributed to the predictions of RD. Conclusions The MKL algorithm identified a likely metabolic marker in the brainstem for RD in major depression. Although 18FDG PET does not investigate specific NT systems, the predictive value of brainstem glucose metabolism on RD scores however indicates that this temperament dimension in the TRD state could be mediated by different monoaminergic systems, all involved in higher order reward-related behavior.

Associations of multidimensional temperament and character profiles with cognition and sensorimotor gating in individuals at risk for schizophrenia-spectrum disorders: preliminary findings

Cloninger’s biopsychological model for personality distinguishes between Temperament [Novelty Seeking, Harm Avoidance (HA), Reward Dependence (RD), Persistence (PS)], and Character [Self-Directedness (SD), Cooperativeness (CO), Self-Transcendence (ST)] traits. Cloninger has also described three sets of complex interactions among these traits, which can be summarized as a linked network of three cubes. Within each cube, the different combinations of the sub-dimensions formulate multidimensional profiles that describe personality more accurately compared with their individual constituents. The aim of the present study was to examine differences of these multidimensional profiles in cognitive functions and Prepulse Inhibition (PPI) in unaffected relatives of schizophrenia-spectrum patients and control individuals. We assessed 114 unaffected relatives of schizophrenia-spectrum patients and 122 controls for Temperament/Character traits, a wide range of cognitive functions, and PPI of the acoustic startle reflex. The relatives had higher Ηarm Avoidance and Self-Transcendence along with lower Reward Dependence, Persistence, Self-Directedness and Cooperativeness scores as well as lower PPI and poorer cognition compared with controls. We also found a) unequal distribution of relatives and controls in several “disadvantageous” profiles associated with the schizophrenia-spectrum, b) the Schizotypal/Disorganized, Apathetic and Fragile profiles had poorer emotional decision making and attention switching, respectively, compared with their “advantageous” counterparts and c) the Adventurous, Independent, Bossy and Resilient profiles had higher PPI compared with their counterparts. These findings further highlight the significance of personality determinants of cognitive processes and have potential implications in early intervention programs in the schizophrenia-spectrum.

Personality traits mediate the association between perceived parental bonding and well-being in adult volunteers from the community

Background Previous studies reported that subjective well-being in adulthood correlates with perceived parental bonding in childhood as well as personality traits. However, whether personality traits mediate the effect of perceived parental bonding on well-being or not has not been reported to date. In this study, we hypothesized that ‘parental care and overprotection’ in childhood affect ‘well-being’ in adulthood through various ‘personality traits’, and analyzed this using structural equation modeling. Methods A total of 402 adult volunteers from the community provided responses to the following questionnaires: 1) Parental Bonding Instrument, 2) Temperament and Character Inventory, and 3) The Subjective Well-being Inventory. Two structural equation models were designed and the maximum likelihood estimation method was used for covariance structure analysis. Results Parental care in childhood directly increased well-being in adulthood and indirectly increased it through personality traits (harm avoidance, reward dependence, and self-directedness). Parental overprotection in childhood had no direct effect on well-being in adulthood but decreased well-being in adulthood indirectly through personality traits (harm avoidance, reward dependence, and self-directedness) and increased it through one personality trait (self-transcendence). Conclusions This study showed that the influences of perceived parental bonding on well-being in adulthood are mediated by self-directedness, harm avoidance, reward dependence, and self-transcendence among the seven personality dimensions evaluated by the Temperament and Character Inventory.

Right Posterior Insula and Putamen Volume Mediate the Effect of Oxytocin Receptor Polygenic Risk for Autism Spectrum Disorders on Reward Dependence in Healthy Adults

Much evidence indicates the influence of the oxytocin receptor (OXTR) gene on autism spectrum disorders (ASDs), a set of disorders characterized by a range of deficits in prosocial behaviors, which are closely related to the personality trait of reward dependence (RD). However, we do not know the effect of the OXTR polygenic risk score for ASDs (OXTR-PRSASDs) on RD and its underlying neuroanatomical substrate. Here, we aimed to investigate associations among the OXTR-PRSASDs, gray matter volume (GMV), and RD in two independent datasets of healthy young adults (n = 450 and 540). We found that the individuals with higher OXTR-PRSASDs had lower RD and significantly smaller GMV in the right posterior insula and putamen. The GMV of this region showed a positive correlation with RD and a mediation effect on the association between OXTR-PRSASDs and RD. Moreover, the correlation map between OXTR-PRSASDs and GMV showed spatial correlation with OXTR gene expression. All results were highly consistent between the two datasets. These findings highlight a possible neural pathway by which the common variants in the OXTR gene associated with ASDs may jointly impact the GMV of the right posterior insula and putamen and further affect the personality trait of RD.