Systematic Cortical Folding Patterns in Human and Non-Human Primate Populations

The cerebral cortex, the outer layer of the brain, has intricate folds with gyral ridges and sulcal valleys. Most notably, gyri are consistently thicker than sulci. However, the exact mechanism of this thickness difference remains elusive, intriguing researchers across multiple disciplines and raising the question of what drives it - whether intrinsic cellular and developmental processes contribute, or whether physical, mechanical, and geometric factors play a primary role. To gain insight into this complex phenomenon, it is crucial to analyze the correlations between cortical thickness and morphology at finer scales during the development of human brain growth and in various other primates. Therefore, this dissertation has examined local and global variations in cortical thickness and morphology in human and non-human primate populations, including different species with different brain sizes and folding patterns to address this issue. In addition, this dissertation has compared primate and human brain developmental trajectories, highlighting differences and drawing inferences about primate cortical folding. The overall goal is to uncover universal principles that govern the relationship between cortical thickness and morphology, thereby shedding light on the mechanisms behind brain growth, development, and organization.