Approved for Kids

Kevin Lewis

January 09, 2022

Does Taekwondo improve children's self-regulation? If so, how? A randomized field experiment
Terry Ng-Knight et al.
Developmental Psychology, forthcoming

Emerging evidence suggests interventions can improve childhood self-regulation. One intervention approach that has shown promise is Taekwondo martial arts instruction, though little is known about its acceptability among stakeholders or its mechanisms of effect. We extend evidence on Taekwondo interventions in three ways: (a) testing the efficacy of a standard introductory course of Taekwondo, (b) assessing the acceptability of Taekwondo instruction among school children, and (c) investigating two self-regulatory mechanisms by which Taekwondo may operate (executive functions and motivation). This article reports findings from a randomized control trial implementing a standard 11-week beginners' course of Taekwondo. Participants were from a mixed-sex, nonselective U.K. primary school (N = 240, age range 7 to 11 years). Measures of self-regulation included teacher-rated effortful control, impulsivity, prosocial behavior, and conduct problems; computer-based assessments of executive functions; and child self-reported expectancies and values to use self-regulation. Postintervention, children in the Taekwondo condition were rated by teachers as having fewer symptoms of conduct problems and better effortful control (specifically attentional control), and they also had better executive attention assessed by a flanker task. Effects were not found for teacher-rated inhibitory control, activation control, impulsivity, and prosocial behavior or for assessments of response inhibition, verbal working memory, and switching. Taekwondo was rated very positively by children. Finally, there was evidence that children who completed Taekwondo classes reported higher expectancies and values to use self-regulation and that expectancies and values mediated intervention effects on self-regulation. We conclude that short standard Taekwondo courses are well received by pupils, improve attentional self-regulation, and reduce symptoms of conduct problems. 

Parents think - incorrectly - that teaching their children that the world is a bad place is likely best for them
Jeremy Clifton & Peter Meindl
Journal of Positive Psychology, forthcoming

Primal world beliefs ('primals') are beliefs about the world's basic character, such as the world is dangerous. This article investigates probabilistic assumptions about the value of negative primals (e.g., seeing the world as dangerous keeps me safe). We first show such assumptions are common. For example, among 185 parents, 53% preferred dangerous world beliefs for their children. We then searched for evidence consistent with these intuitions in 3 national samples and 3 local samples of undergraduates, immigrants (African and Korean), and professionals (car salespeople, lawyers, and cops;), examining correlations between primals and eight life outcomes within 48 occupations (total N=4,535) . As predicted, regardless of occupation, more negative primals were almost never associated with better outcomes. Instead, they predicted less success, less job and life satisfaction, worse health, dramatically less flourishing, more negative emotion, more depression, and increased suicide attempts. We discuss why assumptions about the value of negative primals are nevertheless widespread and implications for future research. 

The effects of maternal input on language in the absence of genetic confounds: Vocabulary development in internationally adopted children
Joseph Coffey et al.
Child Development, forthcoming

Previous studies have found correlations between parent input and child language outcomes, providing prima facie evidence for a causal relation. However, this could also reflect the effects of shared genes. The present study removed this genetic confound by measuring English vocabulary growth in 29 preschool-aged children (21 girls) aged 31-73 months and 17 infants (all girls) aged 15-32 months adopted from China and Eastern Europe and comparing it to speech produced by their adoptive mothers. Vocabulary growth in both groups was correlated with maternal input features; in infants with mean-length of maternal utterance, and in preschoolers with both mean-length of utterance and lexical diversity. Thus, input effects on language outcomes persist even in the absence of genetic confounds. 

"Fast" women? The effects of childhood environments on women's developmental timing, mating strategies, and reproductive outcomes
Tran Dinh, Martie Haselton & Steven Gangestad
Evolution and Human Behavior, forthcoming

The fast-slow paradigm of life history theory has been a popular approach to individual differences in the evolutionary behavioral sciences. Currently, however, the fast-slow paradigm faces several theoretical and empirical challenges. Motivated by questions regarding the validity of certain assumptions of the paradigm, the current study provides an empirical investigation of human female "fast" versus "slow" strategies. In a sample of 1867 women recruited using MTurk, we use structural equation modeling (SEM) to test whether childhood exposure to different environmental variables had unique effects on proposed life history traits, whether mediated by - or independent of - pubertal timing. Models also test whether the proposed life history traits covary with one another as expected by the paradigm. Data reveal that exposure to violence and poor health in particular, but not environmental harshness or unpredictability in general, had significant effects on pubertal timing. Pubertal timing appeared to mediate effects of childhood environments on age at sexual debut, but not any other adult outcome (e.g., sociosexual orientations, reproductive outcomes). Some associations with mating strategies were incompatible with assumptions of the prevailing fast-slow paradigm; for instance, greater short-term mating orientation was positively associated with childhood socioeconomic status and negatively associated with offspring number. These results highlight the need for a new or revised theoretical approach to understanding developmental, mating, and reproductive strategies. 

When friendships surpass parental relationships as predictors of long-term outcomes: Adolescent relationship qualities and adult psychosocial functioning
Joseph Allen et al.
Child Development, forthcoming

Perceptions of adolescent-parent and adolescent-peer relationship qualities, and adolescents' attachment states of mind were examined as predictors of adult social and romantic relationship quality, depressive symptoms, and work performance. Adolescents (86 male, 98 female; 58% White, 29% African American, 8% mixed race/ethnicity, 5% other groups) were followed from age 13 to 24 via observational, self-, parent-, and close friend-reports. Adolescent close friendship quality was a significantly better predictor of adult peer and romantic outcomes, work performance, and depressive symptoms than parental reports of the parent-teen relationship; attachment security was also a strong predictor of numerous outcomes. Results are interpreted as reflecting the difficulty for parents judging parent-teen relationship quality and as reflecting the growing importance of close friendships during this period. 

Preschool executive function and adult outcomes: A developmental cascade model
Sammy Ahmed et al.
Developmental Psychology, December 2021, Pages 2234-2249

The present study examined longitudinal associations between preschoolers' executive function (EF) and adult educational attainment, impulse control, and general health directly and through its cascading effects on childhood and adolescent EF using a large, national, and prospective longitudinal sample of participants. Data were drawn from the National Institute of Child Health and Human Development study of Early Child Care and Youth Development (NICHD SECCYD) and included a diverse sample (52% male at birth; 76% White; 13% Black; 6% Hispanic; and 5% other; 14.23 mean years of maternal education) of 1,364 participants born in 1991 and followed through age 26. Four main findings emerged. First, we observed significant bivariate relations between EF measured at 54 months and adult educational attainment (r = .36, p < .01), and impulse control (r = .11, p = .01). Second, early EF measured during preschool and childhood explained variance in adult educational attainment and impulse control above and beyond adolescent EF. Third, childhood EF mediated the association between preschool EF and adult educational attainment and impulse control but did not operate through adolescent EF. Finally, neither preschool EF nor EF measured at other developmental stages predicted health during adulthood. Together, these findings shed light on the direct and cascading influences of EF across development on important domains of adult functioning.


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