During adolescence the foundation of adult neurocognitive trajectories is being established. Studies will be presented that characterize neurobiological mechanisms that provide evidence for unique developmental plasticity and specialization underlying this maturational period. We performed longitudinal studies using an accelerated cohort design spanning 10-30 years of age using high-field 7T MRI and EEG. We investigated the shape of cognitive development and reward processing and applied multimodal neuroimaging to measure concomitant developmental changes reflecting plasticity in neural activity (EEG), myelination (MRI R1), glutamate/GABA balance (MRSI) in prefrontal cortex, dopaminergic function (striatal tissue iron) in limbic systems and their connectivity.