Early environment and neurobehavioral development predict adult temperament clusters

Temperament and longitudinal changes in physical activity - the Northern Finland Birth Cohort 1966 Study

BACKGROUND

Insufficient physical activity is risk factor for morbidity and premature mortality. This population-based birth cohort study investigated the cross-sectional and longitudinal associations between self-reported temperament at age 31 and self-reported leisure-time moderate to vigorous physical activity (MVPA) levels and changes thereof from the age of 31 to the age of 46 years.

METHODS

The study population comprised 3,084 subjects (1,359 male and 1,725 female) from the Northern Finland Birth Cohort 1966. MVPA was self-reported at ages 31 and 46 years. Novelty seeking, harm avoidance, reward dependence, and persistence and their subscales were measured using Cloninger's Temperament and Character Inventory at age 31. Four temperament clusters were used in the analyses: persistent, overactive, dependent, and passive. Logistic regression was used to evaluate the relationship between temperament and MVPA.

RESULTS

The persistent and overactive temperament profiles at age 31 were positively associated with higher MVPA levels both in young adulthood and in midlife, while the passive and dependent temperament profiles were associated with lower MVPA levels. The overactive temperament profile was associated with a decrease in MVPA levels from young adulthood to midlife among males.

CONCLUSION

A passive temperament profile characterized by high harm avoidance is associated with a higher risk of low MVPA level than other temperament profiles over the life cycle in females. The results suggest that temperament may play a role in determining the level and sustainability of MVPA. Individual targeting and intervention tailoring for promoting physical activity should consider temperament traits.

Sex-specific influence of prenatal air pollutant exposure on neonatal neurobehavioral development and the sensitive window

Increasing evidence indicates the adverse effect of air pollution exposure during pregnancy on neurologic development among children. However, the impact on neurobehavioral development in fetus remains unknown. In 2017, a total of 1193 mother-newborns pairs were enrolled in a birth cohort study in Changsha, China. Exposures to PM_2.5, PM_10, SO₂, CO and NO₂ were determined by using inverse distance weighted method based on local monitoring station data. Neurobehavioral measure was administered at 48-72 h postpartum by utilizing the neonatal behavioral neurological assessment (NBNA). Basic information and covariates were collected by face to face interview. Generalized linear regression and multivariable restricted cubic spline function were performed to explore the trimester-specific association and dose-response relationship of maternal air pollution exposure with NBNA score, respectively. In adjusted three-pollutant model, PM_2.5 exposure in trimester 2 was negatively associated with behavior score (β, -0.003; 95% CI, -0.006, -0.001) and the inverse relation was more pronounced in male infants. In addition, PM_2.5 level in the 2nd trimester was negatively related to activetone score (β, -0.012; 95% CI, -0.021, -0.002) in a dose-dependent manner for both genders. Collectively, our results demonstrated that prenatal exposure to PM_2.5 was linked to poor neurobehavioral performance of newborns. The second trimester was the most sensitive time window for the developments of behavior and activetone, and male subject was more vulnerable as compared to females.

Behavioral Traits Associated With Resilience to the Effects of Repeated Social Defeat on Cocaine-Induced Conditioned Place Preference in Mice

The relationship between stress and drug use is well demonstrated. Stress-induced by repeated social defeat (RSD) enhances the conditioned place preference (CPP) induced by cocaine in mice. The phenomenon of resilience understood as the ability of subjects to overcome the negative effects of stress is the focus of increasing interest. Our aim is to characterize the behavior of resilient animals with respect to the effects of RSD on the CPP induced by cocaine. To this end, 25 male C57BL/6 mice were exposed to stress by RSD during late adolescence, while other 15 male mice did not undergo stress (controls). On the 2 days following the last defeat, all the animals carried out the elevated plus maze (EPM) and Hole Board, Social Interaction, Tail Suspension and Splash tests. Three weeks later, all the animals performed the CPP paradigm with a low dose of cocaine (1 mg/kg). Exposure to RSD decreased all measurements related to the open arms of the EPM. It also reduced social interaction, immobility in the tail suspension test (TST) and grooming in the splash test. RSD exposure also increased the sensitivity of the mice to the rewarding effects of cocaine, since only defeated animals acquired CPP. Several behavioral traits were related to resilience to the potentiating effect of RSD on cocaine CPP. Mice that showed less submission during defeat episodes, a lower percentage of time in the open arms of the EPM, low novelty-seeking, high social interaction, greater immobility in the TST and a higher frequency of grooming were those that were resilient to the long-term effects of social defeat on cocaine reward since they behaved like controls and did not develop CPP. These results suggest that the behavioral profile of resilient defeated mice is characterized by an active coping response during episodes of defeat, a greater concern for potential dangers, less reactivity in a situation of inevitable moderate stress and fewer depressive-like symptoms after stress. Determining the neurobehavioral substrates of resilience is the first step towards developing behavioral or pharmacological interventions that increase resilience in individuals at a high risk of suffering from stress.

The Psychometrics of the European Portuguese Version of the Temperament and Character Inventory-Revised

Cloninger's psychobiological model of personality integrates contributions from behavioral genetics, neurobiology, and psychology in the description of the human personality. The temperament and character inventory (TCI) is its assessment instrument. The Brazilian Portuguese version of the TCI has shown good psychometric properties. However, Portuguese spoken in Brazil presents marked and substantial differences to that spoken in Portugal, and no study has yet described the psychometrics of the European Portuguese version. The objective of this study was thus to describe the psychometric properties of the European Portuguese adult version of the TCI (the temperament and character inventory-revised (TCI-R)). This study involved 1400 Portuguese adult participants. The factorial structure of the European Portuguese version was tested using four methods: exploratory factor analysis, orthogonal procrustes rotation analysis, confirmatory factor analysis, and exploratory structural equation modeling. The integration of data coming from these methods suggested that the Portuguese version of the TCI-R presented good structural validity (as revealed by the emergence of the temperament and character structures predicted by theory) and high levels of congruence between the American and the Portuguese versions. An improvement in the goodness of fit of the models for the Portuguese population was achieved by using exploratory structural equation modeling over confirmatory factor analysis. Although some facets registered questionable consistency, all dimensions had acceptable to good consistency (all ≥ .79). These results confirm the validity of the Portuguese TCI-R and its adequacy for use in European Portuguese samples.

The role of childhood maltreatment in the altered trait and global expression of personality in cocaine addiction

BACKGROUND AND AIMS

Drug addictions are debilitating disorders that are highly associated with personality abnormalities. Early life stress (ELS) is a common risk factor for addiction and personality disturbances, but the relationships between ELS, addiction, and personality are poorly understood.

METHODS

Ninety-five research participants were assessed for and grouped by ELS history and cocaine dependence. NEO-FFI personality measures were compared between the groups to define ELS- and addiction-related differences in personality traits. ELS and cocaine dependence were then examined as predictors of personality trait scores. Finally, k-means clustering was used to uncover clusters of personality trait configurations within the sample. Odds of cluster membership across subject groups was then determined.

RESULTS

Trait expression differed significantly across subject groups. Cocaine-dependent subjects with a history of ELS (cocaine+/ELS+) displayed the greatest deviations in normative personality. Cocaine dependence significantly predicted four traits, while ELS predicted neuroticism and agreeableness; there was no interaction effect between ELS and cocaine dependence. The cluster analysis identified four distinct personality profiles: Open, Gregarious, Dysphoric, and Closed. Distribution of these profiles across subject groups differed significantly. Inclusion in cocaine+/ELS+, cocaine-/ELS+, and cocaine-/ELS- groups significantly increased the odds of expressing the Dysphoric, Open and Gregarious profiles, respectively.

CONCLUSIONS

Cocaine dependence and early life stress were significantly and differentially associated with altered expression of individual personality traits and their aggregation as personality profiles, suggesting that individuals who are at-risk for developing addictions due to ELS exposure may benefit from personality centered approaches as an early intervention and prevention.