This paper introduces a literature from outside the field of education research and policy that we argue has potential to enhance both policy and practice. This field, behavioral genetics, has amassed highly replicable findings spanning more than half a century. Although no necessary policy implications follow from the evidence we review here,…

Recent years have witnessed a growing interest in case studies and surveys by researchers of second language acquisition (SLA) and cognitive (neuro-)science to probe into the group of exceptionally talented multilingual learners or polyglots who can understand and speak an impressive number of multiple foreign languages other than their own mother…

Conoley, Powers, and Gutkin (2020) called for an increased emphasis on models of psychological service delivery that are primarily indirect, adult-focused, and geared toward systems-level change in the schools. They asserted that research in school psychology should not focus on the problems of individual children and youth but address the…

In this article, Peter Molenaar responds to three commentaries (this issue) on his article, "An Interpretation of Part of Gilbert Gottlieb's Legacy: Developmental Systems Theory Contra Developmental Behavior Genetics." He addresses aspects of relational developmental systems (RDS) mentioned and questions raised in each of the…

The concepts and paradigms "development", "evolution", and "developmental behavior genetics" target, in their statements, populations. The laws of genetics and evolution are supposed to apply to every single case in a population. It can be counted among the major contributions of Gottlieb (1992, 1995) to have pointed…

Molenaar's (2015) article concerns Developmental Systems Theory (DST) in relation to behavior genetics and he presents implications of DST for empirical research, especially the need for subject-specific studies. In this commentary, the article is discussed from a broader developmental science perspective, particularly regarded through the lens of…

The main theme of this paper concerns the persistent critique of Gilbert Gottlieb on developmental behavior genetics and my reactions to this critique, the latter changing from rejection to complete acceptation. Concise characterizations of developmental behavior genetics, developmental systems theory (to which Gottlieb made essential…

Epigenetic modifications of chromatin structure provide a mechanistic interface for gene-environment interactions that impact the individualization of health trajectories across the lifespan. A growing body of research indicates that dysfunctional epigenetic regulation contributes to poor cognitive outcomes among aged populations. Here we review…

We present a review of empirical evidence that suggests that a substantial portion of phenotypic variance is due to nonlinear (epigenetic) processes during ontogenesis. The role of such processes as a source of phenotypic variance in human behaviour genetic studies is not fully appreciated. In addition to our review, we present simulation studies…

Individual differences in psychophysiological function have been shown to influence the balance between flexibility and distractibility during attentional set-shifting [e.g., Dreisbach et al. (2005). Dopamine and cognitive control: The influence of spontaneous eyeblink rate and dopamine gene polymorphisms on perseveration and distractibility.…

Does the choice of test for assessing reading comprehension influence the outcome of genetic analyses? A twin design compared two types of reading comprehension tests classified as primarily associated with word decoding (RC-D) or listening comprehension (RC-LC). For both types of tests, the overall genetic influence is high and nearly identical.…

Objective: Child and adolescent psychiatry is rife with examples of the sustained effects of early experience on brain function. The study of behavioral genetics provides evidence for a relation between genomic variation and personality and with the risk for psychopathology. A pressing challenge is that of "conceptually" integrating findings from…

Objective: To review the methodology of behavior genetics studies addressing research questions that go beyond simple heritability estimation and illustrate these using representative research on childhood and adolescent anxiety and depression. Method: The classic twin design and its extensions may be used to examine age and gender differences in…

The study of resilience in maltreated children reveals the possibility of coping processes and resources on multiple levels of analysis as children strive to adapt under conditions of severe stress. In a maltreating context, aspects of self-organization, including self-esteem, self-reliance, emotion regulation, and adaptable yet reserved…

This paper presents a new perspective on the transition from early to middle childhood (i.e., human juvenility), investigated in an integrative evolutionary framework. Juvenility is a crucial life history stage, when social learning and interaction with peers become central developmental functions; here it is argued that the "juvenile transition"…