Structural changes during fetal development of the gyrified brain: clues on determinants of cortical folding

During fetal development the human brain transforms from a smooth-surfaced organ to one with many folds. Interestingly, not all mammalian brains undergo cortical folding, and of those that do, folding complexity varies greatly between species. Within species, the locations of folds remain consistent between individuals, but little is known about the underlying driver/s of the location-specific development of cortical folds. This thesis explores cortical folding by focussing on cell and fibre arrangement in the fetal sheep and comparing the latter with the ferret, another folding species, and the spiny mouse, a species known not to possess any cortical folds.