A blueprint of the developing mind

Brain development during pregnancy is characterized by tremendous brain growth and the construction of connections between communicating brain regions (brain networks). This makes the fetal period essential for normal development and perturbations to these processes render the brain at risk for neurodevelopmental deficits. Mapping and understanding global fetal and neonatal brain growth in vivo are great challenges, data is sparse and multimodal approaches are needed to fill the gap in our knowledge on neuroimaging interpretation. Recent advances in MRI now enable longitudinal study of the fetal and neonatal brain making detailed measurements of brain growth possible. For our studies, we used data from different resources including the first Dutch cohort of healthy pregnant participants that underwent MRI (YOUth study). The main aims of this thesis are: 1) to map the tremendous structural transformation and maturation of the developing brain in utero and neonatal period, both in healthy individuals and preterm born infants; 2) to reveal its functional blueprint in the second half of pregnancy. Different findings on fetal and neonatal MRI are discussed, with a focus on connectome (brain networks) development. Using fetal fMRI, this work shows a large overlap of fetal and adult functional networks, revealing that the blueprint of our brain is established before birth. Other findings on novel baby-brain MRI analyzing techniques, cortical chemoarchitecture and functional connectivity, cortical expansion and the association with gene expression patterns, will be discussed as well