Stress and the brain: how experiences and exposures across the life span shape health, development, and learning in adolescence

Individual differences in accumbofrontal tract integrity relate to risky decisions under stress in adolescents and adults

Psychosocial stress increases risky decision-making (DM). It is widely accepted that individual variation in neural phenotypes underlie variability in this behavioral tendency in adults, but is less examined in adolescents. Our goal was to test the hypothesis that the relation between neural phenotypes and stress-related risky DM is better characterized by individual variation than by age. Using diffusion tensor imaging (DTI) tractography to characterize the accumbofrontal tract, we determined if it uniquely moderated how stress affects risky DM, over and above age. A daily diary design monitored participants’ daily stress for two weeks. Participants completed a DTI scan and performed a task in which decisions varied by expected value, once each on a day when they endorsed feeling higher (and lower) than usual levels of stress. Multilevel logistic regression analyses revealed that all participants were more likely to take risks as expected reward value increased; this behavior was greater under high versus low stress for individuals with low accumbofrontal tract integrity, whereas DM was less influenced by stress for individuals with high accumbofrontal tract integrity, regardless of age. Results suggest that individual differences in brain structure may be more germane to characterizing risky decisions in adolescents, rather than ontogeny.

ATTACHMENT AND BIOBEHAVIORAL CATCH-UP: A SYSTEMATIC REVIEW

Attachment Biobehavioral Catch-up (ABC; Dozier et al., 2006) is a 10-week, in-home intervention primarily for early childhood aged children (ages 6 months-2 years). The ABC intervention seeks to teach parents how to provide nurturing care and engage in appropriate interactions with their children. ABC has been identified as a Level 1 evidence-based practice by the California Evidence-Based Clearinghouse for Child Welfare. However, to date, there has been no systematic review presenting the overall evidence behind ABC available in a peer-reviewed journal. The objective of this review is to address this gap by synthesizing prior literature and evidence, specifically evidence from randomized control trials (RCTs), regarding the effectiveness of the ABC intervention and to determine the contexts in which the intervention has been implemented. To complete this review, literature was searched across three bibliographic databases and relevant Web sites. Only RCTs examining child outcomes were included in the review. Using identified search procedures, 10 articles discussing RCTs which tested the efficacy of ABC were identified. Findings indicate that ABC is effective, when implemented with child-welfare-involved children, at improving emotion regulation, improving externalizing and internalizing behaviors, increasing normative developmental functioning, and attachment quality. Sample information from the 10 RCTs identified is presented as well as additional study characteristics.

Relationship among family environment, self-control, friendship quality, and adolescents' smartphone addiction in South Korea: Findings from nationwide data

Background

Many studies have examined the negative impact on smartphone addiction in adolescents. Recent concerns have focused on predictors of smartphone addiction. This study aimed to investigate the association of adolescents’ smartphone addiction with family environment (specifically, domestic violence and parental addiction). We further investigated whether self-control and friendship quality, as predictors of smartphone addiction, may reduce the observed risk.

Methods

We used the 2013 national survey on internet usage and utilization data from the National Information Agency of Korea. Information on exposure and covariates included self-reported experience of domestic violence and parental addiction, sociodemographic variables, and other variables potentially related to smartphone addiction. Smartphone addiction was estimated using a smartphone addiction proneness scale, a standardized measure developed by national institutions in Korea.

Results

Adolescents who had experienced domestic violence (OR = 1.74; 95% CI: 1.23–2.45) and parental addiction (OR = 2.01; 95% CI: 1.24–3.27) were found to be at an increased risk for smartphone addiction after controlling for all potential variables. Furthermore, on classifying adolescents according to their level of self-control and friendship quality the association between domestic violence and parental addiction, and smartphone addiction was found to be significant in the group with adolescents with lower levels of self-control (OR = 2.87; 95% CI: 1.68–4.90 and OR = 1.95; 95% CI: 1.34–2.83) and friendship quality (OR = 2.33; 95% CI: 1.41–3.85 and OR = 1.83; 95% CI: 1.26–2.64).

Conclusion

Our findings suggest that family dysfunction was significantly associated with smartphone addiction. We also observed that self-control and friendship quality act as protective factors against adolescents’ smartphone addiction.

Childhood Abuse Experiences and the COMT and MTHFR Genetic Variants Associated With Male Sexual Orientation in the Han Chinese Populations: A Case-Control Study

BACKGROUND

Although it is widely acknowledged that genetic and environmental factors are involved in the development of male homosexuality, the causes are not fully understood.

AIM

To explore the association and interaction of childhood abuse experiences and genetic variants of the catechol-O-methyltransferase (COMT) and methylenetetrahydrofolate reductase (MTHFR) genes with the development of male homosexuality.

METHODS

A case-control study of 537 exclusively homosexual men and 583 exclusively heterosexual men was conducted, with data collected from March 2013 to August 2015. Data were analyzed using χ² tests and logistic regression models.

OUTCOMES

Sociodemographic characteristics, childhood abuse experiences, and polymorphisms of COMT at rs4680, rs4818, and rs6267 and MTHFR at rs1801133.

RESULTS

More frequent occurrence of physical (adjusted odds ratio [aOR] = 1.78), emotional (aOR = 2.07), and sexual (aOR = 2.53) abuse during childhood was significantly associated with the development of male homosexuality. The polymorphisms of MTHFR at rs1801133 and COMT at rs4818 also were significantly associated with the development of male homosexuality in the homozygote comparisons (T/T vs C/C at rs1801133, aOR = 1.68; G/G vs C/C at rs4818, aOR = 1.75). In addition, significant interaction effects between childhood abuse experiences and the COMT and MTHFR genetic variants on the development of male homosexuality were found.

CLINICAL TRANSLATION

This is the first time that an association of childhood abuse, COMT and MTHFR genetic variants, and their interactions with development of male homosexuality was exhaustively explored, which could help provide new insight into the etiology of male homosexuality.

STRENGTHS AND LIMITATIONS

Because homosexual men are a relatively obscure population, it was impossible to select the study participants by random sampling, which could lead to selection bias. In addition, because this was a case-control study, recall bias was inevitable, and we could not verify causality.

CONCLUSIONS

Childhood abuse and the COMT and MTHFR genetic variants could be positively associated with the development of homosexuality. However, it remains unknown how these factors jointly play a role in the development of homosexuality, and more studies in different ethnic populations and with a larger sample and a prospective design are required to confirm our findings. Qin J-B, Zhao G-L, Wang F, et al. Childhood Abuse Experiences and the COMT and MTHFR Genetic Variants Associated With Male Sexual Orientation in the Han Chinese Populations: A Case-Control Study. J Sex Med 2018;15:29-42.

Neighborhood Safety and Major Depressive Disorder in a National Sample of Black Youth; Gender by Ethnic Differences

Adolescence is a developmental period marked by increased stress, especially among Black youth. In addition to stress related to their developmental transition, social factors such as a perceived unsafe neighborhood impose additional risks. We examined gender and ethnic differences in the association between perceived neighborhood safety and major depressive disorder (MDD) among a national sample of Black youth. We used data from the National Survey of American Life - Adolescents (NSAL-A), 2003-2004. In total, 1170 Black adolescents entered the study. This number was composed of 810 African American and 360 Caribbean Black youth (age 13 to 17). Demographic factors, perceived neighborhood safety, and MDD (Composite International Diagnostic Interview, CIDI) were measured. Logistic regressions were used to test the association between neighborhood safety and MDD in the pooled sample, as well as based on ethnicity by gender groups. In the pooled sample of Black youth, those who perceived their neighborhoods to be unsafe were at higher risk of MDD (Odds Ratio [OR] = 1.25; 95% Confidence Interval [CI] = 1.02-1.51). The perception that one's neighborhood is unsafe was associated with a higher risk of MDD among African American males (OR=1.41; 95% CI = 1.03-1.93) but not African American females or Caribbean Black males and females. In conclusion, perceived neighborhood safety is not a universal psychological determinant of MDD across ethnic by gender groups of Black youth; however, policies and programs that enhance the sense of neighborhood safety may prevent MDD in male African American youth.

Comparing the Rates of Early Childhood Victimization across Sexual Orientations: Heterosexual, Lesbian, Gay, Bisexual, and Mostly Heterosexual

Few studies have examined the rates of childhood victimization among individuals who identify as "mostly heterosexual" (MH) in comparison to other sexual orientation groups. For the present study, we utilized a more comprehensive assessment of adverse childhood experiences to extend prior literature by examining if MH individuals' experience of victimization more closely mirrors that of sexual minority individuals or heterosexuals. Heterosexual (n = 422) and LGB (n = 561) and MH (n = 120) participants were recruited online. Respondents completed surveys about their adverse childhood experiences, both maltreatment by adults (e.g., childhood physical, emotional, and sexual abuse and childhood household dysfunction) and peer victimization (i.e., verbal and physical bullying). Specifically, MH individuals were 1.47 times more likely than heterosexuals to report childhood victimization experiences perpetrated by adults. These elevated rates were similar to LGB individuals. Results suggest that rates of victimization of MH groups are more similar to the rates found among LGBs, and are significantly higher than heterosexual groups. Our results support prior research that indicates that an MH identity falls within the umbrella of a sexual minority, yet little is known about unique challenges that this group may face in comparison to other sexual minority groups.

Multiple early victimization experiences as a pathway to explain physical health disparities among sexual minority and heterosexual individuals

Prior research shows that health disparities exist between sexual minority and heterosexual individuals. We extend the literature by testing if the higher prevalence of childhood victimization experienced by sexual minority individuals accounts for lifetime health disparities. Heterosexual (n = 422) and sexual minority (n = 681) participants were recruited on-line in North America. Respondents completed surveys about their childhood victimization experiences (i.e., maltreatment by adults and peer victimization) and lifetime physician-diagnosed physical health conditions. Results showed that sexual minority individuals experienced higher prevalence of childhood victimization and lifetime physical health problems than heterosexuals. Mediation analyses indicated that maltreatment by adults and peer bullying explained the health disparities between sexual minority individuals and heterosexuals. This study is the first to show that multiple childhood victimization experiences may be one pathway to explain lifetime physical health disparities. Intervention programs reducing the perpetration of violence against sexual minority individuals are critical to reduce health care needs related to victimization experiences.