Fear and brain maturation
Fear is a response to perceived threat, present already in infants and changes over the course of development from concrete threats such as the dark and animals in childhood to abstract threats such as social failure and worry about the future in adolescents and adults. To study learning and memory mechanisms underlying fears, fear conditioning is often used. In this context, fear acquisition is the pairing of an initially neutral stimulus with an aversive response. During fear extinction, repeated exposure of a feared stimulus leads to a gradual attenuation of the fear response. Fear acquisition has been demonstrated in children as young as 2 years old, with a stronger pairing between the neutral stimulus and the fear response with increasing age, whereas fear extinction is impaired in adolescents as compared to children and adults. However, it is unknown how these developmental changes in fear conditioning are related to brain maturation and the surge in sex hormones in adolescence. In this project, we will examine how changes in fear acquisition and extinction from childhood to adulthood relate to changes in the brain and hormonal exposure. Children, adolescents, and adults will undergo fear acquisition and extinction as well as advanced neuroimaging. The project will increase our understanding of how basic mechanisms underlying acquisition and persistence of fears are related to the brain and sex hormones, and if these relations change over the course of development.