Generation
Child volunteers in a women's paramilitary organization in World War II have accelerated reproductive schedules
Robert Lynch et al.
Nature Communications, May 2020
Abstract:
Understanding how conditions experienced during development affect reproductive timing is of considerable cross-disciplinary interest. Life-history theory predicts that organisms will accelerate reproduction when future survival is unsure. In humans, this can be triggered by early exposure to mortality. Previous studies, however, have been inconclusive due to several confounds that are also likely to affect reproduction. Here we take advantage of a natural experiment in which a population is temporarily divided by war to analyze how exposure to mortality affects reproduction. Using records of Finnish women in World War II, we find that young girls serving in a paramilitary organization wait less time to reproduce, have shorter inter-birth intervals, and have more children than their non-serving peers or sisters. These results support the hypothesis that exposure to elevated mortality rates during development can result in accelerated reproductive schedules and adds to our understanding of how participation in warfare affects women.
The Earliest Origins of Genetic Nurture: The Prenatal Environment Mediates the Association Between Maternal Genetics and Child Development
Emma Armstrong-Carter et al.
Psychological Science, forthcoming
Abstract:
Observed genetic associations with educational attainment may be due to direct or indirect genetic influences. Recent work highlights genetic nurture, the potential effect of parents' genetics on their child's educational outcomes via rearing environments. To date, few mediating childhood environments have been tested. We used a large sample of genotyped mother-child dyads (N = 2,077) to investigate whether genetic nurture occurs via the prenatal environment. We found that mothers with more education-related genes are generally healthier and more financially stable during pregnancy. Further, measured prenatal conditions explain up to one third of the associations between maternal genetics and children's academic and developmental outcomes at the ages of 4 to 7 years. By providing the first evidence of prenatal genetic nurture and showing that genetic nurture is detectable in early childhood, this study broadens our understanding of how parental genetics may influence children and illustrates the challenges of within-person interpretation of existing genetic associations.
Sibling Correlation in Educational Attainment: A Test of Genetic Nurture
John Cawley et al.
NBER Working Paper, June 2020
Abstract:
The educational attainment of siblings is highly correlated. We test for a specific type of peer effect between siblings in educational attainment: genetic nurture. Specifically, we test whether a person's educational attainment is correlated with their sibling's polygenic score (PGS) for educational attainment, controlling for their own PGS for educational attainment. Models estimated using genetic data in the National Longitudinal Survey of Adolescent to Adult Health (Add Health) yield strong evidence of such genetic nurture between siblings, and this result is robust to alternative measures of educational attainment and different measures of polygenic score.
Genetic architecture of Environmental Sensitivity reflects multiple heritable components: A twin study with adolescents
Elham Assary et al.
Molecular Psychiatry, forthcoming
Abstract:
Humans differ substantially in how strongly they respond to similar experiences. Theory suggests that such individual differences in susceptibility to environmental influences have a genetic basis. The present study investigated the genetic architecture of Environmental Sensitivity (ES) by estimating its heritability, exploring the presence of multiple heritable components and its genetic overlap with common personality traits. ES was measured with the Highly Sensitive Child (HSC) questionnaire and heritability estimates were obtained using classic twin design methodology in a sample of 2868 adolescent twins. Results indicate that the heritability of sensitivity was 0.47, and that the genetic influences underlying sensitivity to negative experiences are relatively distinct from sensitivity to more positive aspects of the environment, supporting a multi-dimensional genetic model of ES. The correlation between sensitivity, neuroticism and extraversion was largely explained by shared genetic influences, with differences between these traits mainly attributed to unique environmental influences operating on each trait.
Relational permanence and the potential for delinquency among African American adolescents in foster care
Abigail Williams-Butler et al.
Children and Youth Services Review, forthcoming
Abstract:
Social relationships are often seen as a buffer to delinquency. However, they may be correlated with negative outcomes, as delinquency may provide social benefits for adolescents in foster care. Relational permanence - a form of social support characterized by the presence of an ongoing caring and supportive person in the context of the foster care system - is the primary type of social relationship that is explored. Regression analyses were conducted examining whether relational permanence predicted later delinquency. We found an increase in relational permanence over time was correlated with higher levels of delinquency. These findings demonstrate that not all social relationships are correlated with positive outcomes. The multidimensionality of social relationships must be further understood in order to inform targeted interventions for youth in the foster care system. Considerations specifically for African-American adolescents in foster care are also addressed.
Effects of a school readiness intervention on electrophysiological indices of external response monitoring in children in foster care
Jacqueline Bruce et al.
Development and Psychopathology, forthcoming
Abstract:
This study examined the impact of a school readiness intervention on external response monitoring in children in foster care. Behavioral and event-related potential (ERP) data were collected during a flanker task from children who received the Kids In Transition to School (KITS) Program (n = 26) and children who received services as usual (n = 19) before and after the intervention. While there were no significant group differences on the behavioral data, the ERP data for the two groups of children significantly differed. Specifically, in contrast to the children who received services as usual, the children who received the KITS Program displayed greater amplitude differences between positive and negative performance feedback over time for the N1, which reflects early attention processes, and feedback-related negativity, which reflects evaluation processes. In addition, although the two groups did not differ on amplitude differences between positive and negative performance feedback for these ERP components before the intervention, the children who received the KITS Program displayed greater amplitude differences than the children who received services as usual after the intervention. These results suggest that the KITS Program had an effect on responsivity to external performance feedback, which may be beneficial during the transition into kindergarten.