This thesis aimed to investigate the neurobiological mechanisms of adolescent onset depression and anxiety disorders. A longitudinal fMRI study design was used that included both task related brain... Show moreThis thesis aimed to investigate the neurobiological mechanisms of adolescent onset depression and anxiety disorders. A longitudinal fMRI study design was used that included both task related brain activation and resting state functional connectivity. All participants were scanned three times in a six-month period. In between scan sessions the adolescents from the clinical group received treatment as usual. Adolescents from the control group were scanned within the same time interval but did not receive treatment. During a scan session several MRI parameters were collected including task based fMRI (emotional face processing task) and resting state fMRI. We also administered several questionnaires about derpession and anxiety symptomatology. It was demonstrated that adolescents with depressive and anxiety disorders show differentiating patterns of amygdala reactivity and connectivity compared to a healthy control group. Furthermore, using a dimensional approach and taking individual differences in self-reported depression and anxiety symptoms into account highlighted the role of self-reported anxiety symptoms in amygdala reactivity during emotional faces processing. These findings indicate that the amygdala indeed is an important region involved in emotional face processing and that focusing on this region can provide further insights in the development and persistence of depressive and anxiety disorders in adolescents. Show less
One of the most prominent changes in adolescence is social reorientation. In other words, adolescents develop more intimate relationships with peers, they discover what it is like to be involved in... Show moreOne of the most prominent changes in adolescence is social reorientation. In other words, adolescents develop more intimate relationships with peers, they discover what it is like to be involved in a romantic relationship, and they take (social) risks by for example showing risky driving in the presence of friends. Given that social networks with peers become central elements in the adolescent’s life, investigating the role of individual differences related to the development of social reorientation seems highly relevant. This dissertation contributes to a better understanding of stability and change in social reorientation during adolescence by explaining the crucial role of empathy in social interactions from a brain and behavioral perspective. Future research can benefit from the presented studies by applying it to a more detailed analysis of individual differences in this important period in life, which may help to explain why some adolescents are successful in developing social competencies and relationships, whereas others experience difficulties. Eventually, this may lead to the development of interventions for youth who do not cope well with the social requirements from the environments, and help to improve their lives and the lives of individuals around them Show less
