Adolescence is often characterized as a period of increased risk taking and impulsive behavior. Researchers have constructed brain-based models to explain the higher prevalence of risk taking... Show moreAdolescence is often characterized as a period of increased risk taking and impulsive behavior. Researchers have constructed brain-based models to explain the higher prevalence of risk taking during adolescence. It has been hypothesized that brain regions for cognitive control develop relatively slow compared to 'affective' brain regions. An imbalance between the maturity of these brain regions is thought to underlie the increased incidence of risk taking during adolescence. However, results on functional brain development remain contradictory and few studies have investigated the assumptions of imbalance models in large-scale longitudinal studies. In this PhD thesis both cognitive and affective aspects of development were investigated using a combination of functional and structural MRI data, hormonal measures and behavioral assessments, capturing the whole range of adolescence in a large sample of children, adolescents and adults between 8 and 27 years old. The results indicated that, contrary to predictions from imbalance models, brain regions for cognitive control could be recruited even by young children and adolescents, but in different situations than adults. The results have implications for the construction of new theoretical frameworks and may eventually contribute to educational interventions that are better tailored to both the challenges and possibilities of the adolescent brain. Show less
By using innovative paradigms, the present thesis provides convincing evidence that action-effect learning, and sensorimotor processes in general play a crucial role in the development of action-... Show moreBy using innovative paradigms, the present thesis provides convincing evidence that action-effect learning, and sensorimotor processes in general play a crucial role in the development of action- perception and production in infancy. This finding was further generalized to sequential action. Furthermore the thesis suggests that means-selection-, ends-selection information, and action-effect knowledge together feed into a unitary concept of goal. Both these findings have the potential to generate interesting new research question Show less
Assessment procedures are frequent in children's school careers; however, measuring potential for learning has remained a puzzle. Dynamic testing is a method to assess cognitive potential that... Show moreAssessment procedures are frequent in children's school careers; however, measuring potential for learning has remained a puzzle. Dynamic testing is a method to assess cognitive potential that includes training in the assessment process. The goal of this thesis project was to develop a new dynamic test of analogical reasoning for school children. The main aims were to (1) investigate factors that influence children’s differences in performance and change during dynamic testing and (2) examine the predictive value of dynamic measures on children’s school performance. Children showed great variation in cognitive potential. Higher ability children generally required less training and showed greater transfer to other problem sets. Yet, lower ability children tended to improve more during dynamic testing. Performance change during testing appears to be a unique predictor of math and reading achievement, but was unrelated to working memory or cultural background, providing evidence that this may be a separate construct important in the assessment of cognitive potential – especially in culturally diverse schools. This performance change measure, often criticized within classical test theory, has demonstrated its worth when estimated using item response theory models and will hopefully find its place again among the valuable measurement outcomes of children’s potential for learning. Show less
