From his first attempts to explain attachment phenomena in the 1940s through his "Attachment and Loss" trilogy (Bowlby, 1969/1982, 1973, 1980), John Bowlby reformulated the theoretical underpinnings of attachment theory several times. He initially attempted to explain attachment phenomena in psychoanalytic terms. Then he invoked…

Background: Enacting good science in pursuing the international study of positive youth development (PYD) requires using sound developmental theory to formulate questions that are tested through employing rigorous, change-sensitive measures, designs, and data analyses that are aimed at describing, explaining, or optimizing thriving among the…

Purpose: The transition to school and the first years of elementary school education are very sensitive phases for reading development. Reading researchers have established key precursors and developmental steps in these phases. However, how these components interact and affect growth is not well understood yet. The current study from Germany…

By approximately 6 years of age, children can use time-based visual selection to ignore stationary stimuli, already in the visual field and prioritize the selection of newly arriving stimuli. This ability can be studied using preview search, a version of the visual search paradigm with an added temporal component, in which one set of distractors…

This paper examines the genetic ("nature") and environmental ("nurture") influences on why students vary in their reading skills. We review core findings from the field of modern behavioral genetics, a discipline that studies the interplay of genetic and environmental influences, on reading science. Additionally, we provide an…

Girls, more than boys, experience a decrease in the severity of autism symptoms during childhood. It is unclear, however, which specific autistic behaviors change more for girls than for boys. Trajectories of autism symptoms were evaluated using the Autism Diagnostic Observation Schedule-calibrated severity scores (ADOS-CSS). Change in the…

Background: Relational victimization (RV) is a significant threat to adolescent mental health and social adaptation in China. However, its developmental characteristics during the school transition period are poorly understood. Finkelhor's developmental victimology framework provides a comprehensive lens to explore factors influencing RV's…

This article presents the adaptation of the MacArthur Communicative Development Inventory (CDI; Fenson et al., 1993, "Guide and technical manual for the MacArthur Communicative Development Inventories." San Diego, CA: Singular Press; Fenson et al. 1994, Variability in early communicative development. "Monographs of the Society for…

Abstract How do people gather samples of evidence to learn about the world? Adults often prefer to sample evidence from diverse sources--for example, choosing to test a robin and a turkey to find out if something is true of birds in general. Children below age 9, however, often do not consider sample diversity, instead treating non-diverse samples…

Purpose: This study compared and characterized the tense and agreement productivity of boys with fragile X syndrome (FXS), children with developmental language disorder (DLD), and children with typical development (TD) matched on mean length of utterance. Method: Twenty-two boys with FXS (M[subscript age] = 12.22 years), 19 children with DLD…

Play is widely acknowledged as being critical for children's development, yet opportunities for play are becoming more scarce for many children.

Trajectories of stability and change in bullying roles were examined through a longitudinal prospective study of 916 school students followed up biannually from age 11 to 17. Perpetrators and victims had relatively stable trajectories with most of the children remaining in the same role over time or becoming uninvolved. Bully/victim was the most…

We report on an innovative computer-adaptive assessment, the Comprehensive Research-based Early Math Ability Test (CREMAT), using the case of 1st- and 2nd-graders' understanding of geometric measurement. CREMAT was developed with multiple aims in mind, including: (1) be administered with a reasonable number of items, (2) identify the level(s) of…

Hybrid autoregressive-latent growth structural equation models for longitudinal data represent a synthesis of the autoregressive and latent growth modeling frameworks. Although these models are conceptually powerful, in practice they may struggle to separate autoregressive and growth-related processes during estimation. This confounding of change…

The present study explores how identifying with the gender and sexual minority (GSM) community can be an important developmental milestone and potential protective factor for GSM individuals. Cross-sectional data were collected from the United States using Amazon's Mechanical Turk (MTurk) to garner a nationally representative sample of individuals…