Nervous system injury and disease can have broad effects on nerve or brain function, yet the signaling pathways that control nervous system responses to injury remain unclear. Building on previous work in the Freeman lab that showed even partial nerve injury can lead to rapid, widespread changes in neurophysiology in both severed axons and nearby, uninjured "bystander" neurons, Jiun-Min Hsu, Marc Freeman and colleagues recently discovered new details about the role of glial cells to propagate injury signals broadly across the nervous system and actively suppress bystander neuron function. Their work further defines the role of Sarm1/dSarm on controlling such injury responses — with two-phases signaling — and provides new insights into the confounded Sarm1/dSarm mediated nervous system responses. The research was published December 8, 2020 in the journal Neuron.