Mood variability during adolescent development and its relation to sleep and brain development.

Mood swings, or mood variability, are associated with negative mental health outcomes. Since adolescence is a time when mood disorder onset peaks, mood variability during this time is of significant interest. Understanding biological factors that might be associated with mood variability, such as sleep and structural brain development, could elucidate the mechanisms underlying mood and anxiety disorders. Data from the longitudinal Leiden self-concept study (N = 191) over 5 yearly timepoints was used to study the association between sleep, brain structure, and mood variability in healthy adolescents aged 11-21 at baseline in this pre-registered study. Sleep was measured both objectively, using actigraphy, as well as subjectively, using a daily diary self-report. Negative mood variability was defined as day-to-day negative mood swings over a period of 5 days after an MRI scan. It was found that negative mood variability peaked in mid-adolescence in females while it linearly increased in males, and average negative mood showed a similar pattern. Sleep duration (subjective and objective) generally decreased throughout adolescence, with a larger decrease in males. Mood variability was not associated with sleep, but average negative mood was associated with lower self-reported energy. In addition, higher thickness in the dorsolateral prefrontal cortex (dlPFC) compared to same-age peers, suggesting a delayed thinning process, was associated with higher negative mood variability in early and mid-adolescence. Together, this study provides an insight into the development of mood variability and its association with brain structure.

The polygenic and reactive nature of observed parenting.

In Wertz et al. (2019), parents' polygenic scores of educational attainment (PGS-EA) predicted parental sensitive responses to the child's needs for support, as observed in a dyadic task (i.e., observed sensitivity). We aimed to replicate and expand these findings by combining longitudinal data, child genotype data and several polygenic scores in the Generation R Study. Mother-child dyads participated in two developmental periods, toddlerhood (14 months old; n = 648) and early childhood (3-4 years old, n = 613). Higher maternal PGS-EA scores predicted higher observed sensitivity in toddlerhood (b = 0.12, 95% CI 0.03, 0.20) and early childhood (b = 0.16, 95% CI 0.08, 0.24). Child PGS-EA was significantly associated with maternal sensitivity in early childhood (b = 0.11, 95% CI 0.02, 0.21), and the effect of maternal PGS-EA was no longer significant when correcting for child PGS-EA. A latent factor of PGSs based on educational attainment, intelligence (IQ) and income showed similar results. These polygenic scores might be associated with maternal cognitive and behavioral skills that help shape parenting. Maternal PGSs predicted observed sensitivity over and above the maternal phenotypes, showing an additional role for PGSs in parenting research. In conclusion, we replicated the central finding of Wertz et al. (2019) that parental PGS-EA partially explains parental sensitivity. Our findings may be consistent with evocative gene-environment correlation (rGE), emphasizing the dynamic nature of parenting behavior across time, although further research using family trios is needed to adequately test this hypothesis.

Response bias is genetically biased: Another argument for Kagan's philippic against questionnaires in developmental psychology.

One of the concerns of Jerome Kagan (2007) in his article "A Trio of Concerns" was the frequent use of questionnaires in developmental psychology and related disciplines. His main reasons were the minimal overlap between (self-)reported and observed phenotypes, the ambiguity of items, and systematic socioeconomic status (SES) disparities in responding. We wondered whether genetic differences would also influence response bias in cases of ambiguous or even absurd items triggering an acquiescence bias to agree with even impossible question content. We examined the genetic predisposition for the acquiescence response bias in 257 families with twins. Both parents and twins completed a modified Wildman Symptoms Questionnaire and provided salivary DNA samples. From published genome-wide association studies (GWAS), we derived polygenic score (PGS) algorithms for indicators of SES (educational attainment [EA] and income) and for general intelligence (IQ), which were applied to the GWAS results of our participants' DNA. The twins (N = 514 children, 55% monozygotic pairs) were on average 7.92 years old (SD = 0.66), and 51.6% were female. The primary parents were on average 40.48 years old (SD = 4.66), and 91% were female. In 90% of the families, both parents were born in the Netherlands and 91% were from a middle or higher socioeconomic background. Higher PGSs for EA and income but not for IQ predicted less acquiescence response bias in parents and children. In addition to Kagan's reasons for his concerns about questionnaires, we found a genetic predisposition to response bias triggered by the ambiguous form of questions and answers. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Parents' secure base script knowledge predicts observed sensitive caregiving and discipline toward twin children.

The present study investigated associations between parents' secure base script knowledge and parental sensitivity and sensitive discipline in 461 families with 922 same-sex twin children (Mage = 7.00, SD = 2.18). In addition, we explored whether the strength of the associations between parents' secure base script knowledge and parental sensitivity and sensitive discipline were similar for mono- and dizygotic twin siblings. Parental sensitivity was observed during a computerized version of a structured cooperative drawing task (Etch-A-Sketch). Sensitive discipline was observed during a "Don't touch task" or during a "Do-Don't task". Parental sensitivity and discipline strategies were observed twice, once with each twin sibling. Parents' knowledge of the secure base script was measured with the Attachment Script Assessment. Linear mixed model analyses showed that parents with more secure base script knowledge interacted with their twin children in a more sensitive manner and showed more sensitive discipline. These findings show for the first time that parents' secure base script knowledge predicts not only parental sensitivity but also sensitive discipline. Associations between parents' secure base script knowledge and parental sensitivity and sensitive discipline were not impacted by children's similarity in genetic makeup. Future longitudinal studies utilizing multiple measures of sensitivity and discipline across the infancy, childhood, and early adolescence periods could provide more insight into the continuity of relations between secure base script knowledge and parental sensitivity and sensitive discipline. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Conduct Problems and Hair Cortisol Concentrations Decrease in School-Aged Children after VIPP-SD: A Randomized Controlled Trial in Two Twin Cohorts.

The Video-feedback Intervention to promote Positive Parenting and Sensitive Discipline (VIPP-SD) is effective in increasing parental sensitivity and sensitive discipline, and aims to decrease child behavior problems. Changes in quality of parenting may be accompanied by effects on child stress levels. However, studies of VIPP-SD effects on child behavior problems have shown mixed results and there are no studies to date of the effect of the intervention on children's stress levels, as measured by hair cortisol concentration (HCC). Furthermore, differences in intervention effectiveness may be explained by differential susceptibility factors. We hypothesized that the effects of the VIPP-SD on child behavior problems might be moderated by currently available child polygenic scores of differential susceptibility (PGS-DS). In the current pre-registered trial, we randomly assigned 40% of n = 445 families with school-aged twin children to the intervention group. The VIPP-SD was successful in decreasing both children's conduct problems and HCC. Effects were not moderated by available child PGS-DS. We conclude that a brief, home-based video-feedback parenting intervention can decrease child behavior problems and affect the child's stress-related neuroendocrine system as assessed with hair cortisol. In future studies, more specific PGS-DS for externalizing behaviors should be used as well as parental PGS-DS.

Replicating a randomized trial with video-feedback to promote positive parenting in parents of school-aged twins.

In this randomized controlled trial, we investigated the effectiveness of the brief, home-based Video-feedback Intervention to promote Positive Parenting and Sensitive Discipline (VIPP-SD) in parents of 257 school-aged twin pairs (N = 514 children, Mage = 7.92, SD = 0.66), replicating a previous study testing the effectiveness of the intervention in parents with preschool-aged twins (Euser et al., 2021). We conducted two pretests (1 year apart) and one posttest 1 month after the intervention. An age-adequate twin-adapted version of the VIPP-SD was used in primary caregivers (91% female). We examined the main effect of the intervention on observed parental sensitivity and sensitive discipline and on attitudes toward sensitivity and sensitive discipline. We also investigated whether parents who are more susceptible to the environment, as measured by their self- and partner-reported current temperamental reactivity, benefitted more from the intervention. In our sample with older children, the VIPP-SD did not significantly change observed parental sensitivity or sensitive discipline in the intervention group compared to the control group. The VIPP-SD did improve parents' attitude toward sensitivity, but not toward discipline. Intervention effects were not moderated by temperamental reactivity of the parents, providing no support for the differential susceptibility hypothesis. Future research might examine the differential susceptibility hypothesis in parents using stress-reactivity or genetic susceptibility markers instead of self-reported reactive temperament. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Actigraphic sleep and cortisol in middle childhood: A multivariate behavioral genetics model.

To date, behavioral genetic studies investigated either sleep or cortisol levels in middle childhood, but not both simultaneously. Therefore, a pertinent question is the degree to which genetic factors and environmental factor contribute to the correlation between sleep and cortisol levels. To address this question, we employed the classical twin design. We measured sleep in 6-9-year-old twins (N = 436 twin pairs, "Together Unique" study) over four consecutive nights using actigraphy, and we measured morning cortisol on two consecutive days. Sleep duration, sleep efficiency, and wake episodes were used as indicators of sleep. Morning cortisol level was used as cortisol indicator. A structural equation model was fitted to estimate the contribution of additive genetic effects (A), shared (common) environmental effects, (C) and unique environmental effects (E) to phenotypic variances and covariances. Age, cohort, and sex were included as covariates. The heritability of sleep duration, sleep efficiency, and wake episodes were 52%, 45%, and 55%, respectively. Common environmental factors played no significant role. High genetic correlations between sleep duration and sleep efficiency and high genetic correlations between sleep efficiency and wake episodes were found. Shared environmental (29%) and unique environmental factors (53%) explained the variance in morning cortisol levels. Because the sleep and cortisol measures were found to be uncorrelated, we did not consider genetic and environmental contributions to the association between the sleep and cortisol measures. Our findings indicate that sleep duration, sleep efficiency, and wake episodes in children are mostly impacted by genetic factors and by unique environmental factors (including measurement error).