The main objectives were to evaluate efficacy and acceptability of a developmentally sensitive cognitive behavioral therapy for anxiety-based school refusal in adolescence. Twenty school-refusing... Show moreThe main objectives were to evaluate efficacy and acceptability of a developmentally sensitive cognitive behavioral therapy for anxiety-based school refusal in adolescence. Twenty school-refusing adolescents meeting DSM-IV anxiety disorder criteria participated in a non-randomized trial, together with parents and school staff. Outcome was assessed at post-treatment and 2-month follow-up. Treated adolescents showed significant and maintained improvements across primary outcome variables (school attendance; school-related fear; anxiety), with medium to large effect sizes. Half of the adolescents were free of any anxiety disorder at follow-up. Additional improvements were observed across secondary outcome variables (depression; overall functioning; adolescent and parent self-efficacy). The treatment was rated as acceptable by adolescents, parents, and school staff, which may help explain the very low attrition rate. Social anxiety disorder was the most common disorder among adolescents still meeting anxiety disorder criteria at follow-up. Treatment modifications to improve efficacy for school-refusing adolescents presenting with social anxiety disorder are suggested. Show less
It is well known that complex mental abilities develop at least until late adolescence. Yet, there are also skills that children master perfectly, sometimes even better than adults. The goal of... Show moreIt is well known that complex mental abilities develop at least until late adolescence. Yet, there are also skills that children master perfectly, sometimes even better than adults. The goal of this thesis was to learn more about the possibilities of cognitive functioning in children and young adults, and the constraints set by the developing brain. An fMRI training approach was used to examine age- and experience-related effects in the development of working memory and resting-state functional connectivity. More specifically, we studied age differences on task performance and brain activation during a working memory task with various demands and difficulty levels, both before and after 6 weeks of practice with the task. In addition, to learn more about the interaction between different brain regions, we also examined age differences and practice effects on functional connectivity during resting-state. Show less
School refusal is an attendance problem characterized by a young person’s difficulty in going to school, accompanied by emotional distress on the part of the young person and parental attempts to... Show moreSchool refusal is an attendance problem characterized by a young person’s difficulty in going to school, accompanied by emotional distress on the part of the young person and parental attempts to return the young person to regular school attendance. Prolonged absence from school has serious short- and long-term consequences for young people, their families, and schools. Therefore, effective treatment of school refusal is essential. Numerous treatment outcome studies provide evidence for the efficacy of cognitive-behavioural therapy (CBT) for school refusal. Previous research has however indicated that adolescent school refusers may be particularly disturbed and harder to treat. An existing treatment for school-refusing children and adolescents was modified to better account for the impact of developmental variables on engagement in treatment. The studies presented in this dissertation describe the preparation, implementation, and evaluation of the resulting developmentally-appropriate CBT for adolescent school refusal. The treatment was associated with increased school attendance, reduced emotional symptoms, and increased adolescent and parental self-efficacy. Exploratory analyses revealed that several developmental factors were related to treatment outcomes, namely clinician developmental appropriateness, insight, and autonomy. Recommendations for research and clinical practice are made on the basis of these findings, and on the methodological strengths and limitations of the current research. Show less
This thesis studies the normal developmental pattern of social evaluative fears from childhood to adolescence. We have investigated age differences in self-reported social fears and physical... Show moreThis thesis studies the normal developmental pattern of social evaluative fears from childhood to adolescence. We have investigated age differences in self-reported social fears and physical responses during a public speaking task. In addition, youth's perceptions of speaking in public were studied through a short interview. Finally, two aspects of adolescent development are highlighted, namely resistance to peer influence and self-restraint, in the two concluding chapters. The main finding of the thesis is that social evaluative fears seem to increase with age. However, future research needs to develop more developmentally sensitive measures and further investigate the underlying processes of this increase. Show less
The research described in this thesis aimed to gain insight in risky behavior in adolescence, by examining the development of decision-making in relation to brain development. Chapter 1 describes... Show moreThe research described in this thesis aimed to gain insight in risky behavior in adolescence, by examining the development of decision-making in relation to brain development. Chapter 1 describes two existing possible explanations for adolescent risky behavior, the first explanation focuses on the development of cognitive control, and states that adolescents’ immature ability to control their impulses may bias them to act risky. The second explanation focuses on emotional/motivational processes, and suggests that adolescents engage in risky behavior because they respond stronger to the possible rewards associated with risks than children and adults do. Chapters 2, 3, and 7 describe studies on developmental changes in the processes that form the building blocks of more complex decision-making under risk; probability estimation, reward processing and working memory. Chapters 4, 5, and 6 explore the relative contributions of reward sensitivity and cognitive control to decision-making across development. This thesis shows knowledge about brain maturation can inform models of adolescent risky behavior. And that adolescent risk-taking can be explained as the consequence of the earlier maturation of reward related relative to cognitive control related brain circuitry. Show less
To what extent does psychosocial development have an effect on problem behaviour development? And does the effect of this development of psychosocial maturity differ for boys and girls? This thesis... Show moreTo what extent does psychosocial development have an effect on problem behaviour development? And does the effect of this development of psychosocial maturity differ for boys and girls? This thesis focuses on answering these questions. The research that is presented aims to identify relations in levels as well as paths of psychosocial development on problem behaviour. The study uses data from the School project, a longitudinal research project on adolescents that examined (problem) behaviour and relevant relating factors. This research provides insight into psychosocial development, as well as the effect of parental relations and peer relations on problem behaviour prevalence. Show less
The Adult Attachment Interview (AAI) was developed in the early 1980s to measure an adult’s attachment representation. Since then, it has been applied in more than 100 studies. This thesis aimed to... Show moreThe Adult Attachment Interview (AAI) was developed in the early 1980s to measure an adult’s attachment representation. Since then, it has been applied in more than 100 studies. This thesis aimed to shed light on some of the potentials and limitations of the AAI. We found that coherence, which is an important concept in attachment interviews, is not defined similarly by attachment experts, linguists, and non-experts. Therefore, it seems that a measure for coherence cannot make the AAI more easily accessible for non-attachment experts. Secondly, we showed that the attachment representations of adopted adolescents were related (1) to their own autonomy behaviors and mothers’ relatedness behaviors during a discussion task, (2) to the adolescents’ emotional investment in others, and (3) to the adolescents’ perceived support from others. Intelligence and perceived temperament were not associated with the adolescents’ attachment representation. These results support the validity of the AAI when assessed with (adopted) adolescents. Finally, we revealed that the AAI differentiates between adolescents with divergent physiological responses (interbeat interval reactivity) to attachment relevant situations: dismissing adolescents showed less physiological reactivity during the AAI than secure adolescents, while they appeared to be more stressed during a discussion task with their mothers. Show less
