Shown are pathways across the whole mouse brain, captured via diffusion magnetic resonance tractography. Colors depict the average direction of fibers in the brain. Blue represents fibers coursing across the rostral to caudal axis. Red captures fibers coursing across the medial to lateral axis. Green shows fibers coursing across the dorsal to ventral axis. Nicholas Cottam and colleagues mapped these pathways at sequential stages of postnatal development to track how mouse brain circuits mature and compared what they found to human brain circuit maturation. See the article by Cottam et al. for more information on similarities and differences between mouse and human neurodevelopment. Cover image: Christine Charvet