Rapid predator learning in a developing vertebrate brain

Nascent animals are most in need of learning to identify predators due to their vulnerability, yet paradoxically, are generally assumed not to be capable of such rapid, complex learning tasks. Here, a robotic fish-attacker interaction assay showed that larval zebrafish just a week of age learn to identify and avoid a robot following brief minutes-long periods of chase. Whole-brain calcium imaging identified noradrenergic signaling, consistent with a reinforcement signal, that was coupled to activity in populations spread across the larval pallium, subpallium, and habenula. Finally, targeted neural ablations confirmed the necessity of these regions in predator learning. Altogether, we identify a distributed network spanning the larval brain that mediates rapid and efficient learning in a developing vertebrate brain.