Research on infant cognitive development is often statistically insufficiently powerful and replicability is a serious problem. A consortium of four baby labs will replicate two fundamental studies, which play a key role in debates on the learning mechanisms involved in language acquisition (Marcus et al. 1999) and on the cognitive benefits of bilingualism (Kovács and Mehler, 2004). By replicating each study in all four laboratories, we can improve the statistical power of the studies and test the robustness of the original results from these two important infant studies.

This project investigates developmental and individual differences in risky decision making in relation to problem behavior among a Dutch sample of adolescents, across two educational levels and among several ethnic groups. Using an experimental research paradigm designed to elicit real-time risky decision making, a cross-sectional sample of 12-14 year olds and 16-18 year olds will be studied to examine the influence of peers, parents and siblings on risky decision making. Personality and relationship characteristics in relation to risk taking will also be investigated. The adolescents will be followed 12 and 24 months later.

Not everyone develops comparable language skills. The first 1,001 days from conception onwards prove critical for language skills and brain development alike. Unknown is whether these two developmental processes are related. The YOUth cohort study follows >2,000 children’s brain development starting in pregnancy. This project assesses their full language profiles when the same children are 3-6 years old. Next, researchers link language skills to children’s prenatal brain development and the emergence of social brain networks in infancy. Researchers also take into account child- and parental characteristics. This will improve interventions for children in need of speech and language therapy.

We propose to add a seventh and eight bi-annual wave to RADAR, an ongoing longitudinal study. RADAR follows two samples: RADAR young (C1) and RADAR old (C2). The sample of RADAR young consists of 497 adolescents, their families (mother, father and one sibling) and their best friends. The sample of RADAR old consists of 233 adolescents, their families (mother, father and one sibling) and their best friends. The sixth annual wave of data-collection of RADAR young will be completed by June 2011 and the sixth wave of RADAR old has been completed in fall of 2010.

Humans create social bonds by sharing experiences (e.g., during rituals, listening to stories and watching movies together). But when do children become psychologically capable of bonding like this? How does this capacity manifest early in development? And is the family’s smartphone use, which tends to interfere with shared experiences, related to reduced sensitivity to children’s experience sharing? In a series of experiments, I will examine whether 9–18-month-olds act and feel more positively to their partner after sharing an experience, and if this reaction is related to the amount of smartphone use in the family.