For generations, scientists imagined the brain assembling itself like a building — floor by floor, one neuron type at a time. New research from Irene Varela-Martínez at the Institute of Science and Technology Austria overturns that orderly picture, revealing that neural stem cells branch into distinct developmental lineages from the very beginning, each following its own rhythm and scale. The cerebral cortex, it now appears, is not the product of a single sequential program but of parallel stories unfolding simultaneously — a finding that quietly reframes our understanding of how minds are mad