The research group Neuroregeneration is embedded in the division Biological Optomechanics at the Max Planck Institute for the Science of Light and Max-Planck-Zentrum für Physik und Medizin. Our research addresses the question: why are some vertebrates able to regenerate their spinal cord after injury? In mammals, including us humans, spinal cord injury (SCI) leads to permanent physical impairments because severed nerve fibres (axons) do not regrow across the lesion site. In contrast, zebrafish exhibit robust axonal regrowth even after complete transection of the spinal cord, leading to substantial recovery of locomotor function. This offers a vertebrate model to study the parameters required to enable axonal regrowth after SCI. Specifically, we focus on elucidating the composition, regulation and mechanical properties of the non-neural lesion environment, which in contrast to mammals, is permissive for axonal growth in zebrafish. To this end we are using a broad range of state-of-the-art optical imaging technologies, such as Brillouin microscopy, novel 3D in vitro scaffolds made of compliant hydrogel beads, and genetic and molecular biology tools. Our long-term goal is to provide clues on how severed axonal connections can be functionally repaired in the human spinal cord.