In vivo imaging in transgenic songbirds reveals superdiffusive neuron migration in the adult brain

Summary Neuron migration is a key phase of neurogenesis, critical for the assembly and function of neuronal circuits. In songbirds, this process continues throughout life, but how these newborn neurons disperse through the adult brain is unclear. We addressed this question using in vivo two-photon imaging in transgenic songbirds that express GFP in young neurons. In juvenile and adult birds, migratory cells were present at a high density, traveled in all directions, and made frequent course changes. Notably, these dynamic migration patterns were well fit by a superdiffusive model. Simulations revealed that these diffusion-like dynamics were sufficient to disperse new neurons throughout the song nucleus HVC. These results suggest that diffusion-like migration may underlie the formation and maintenance of nuclear brain structures in the postnatal brain and indicate that transgenic songbirds are a useful resource for future studies into the mechanisms of adult neurogenesis. Highlights Transgenic songbirds express GFP in a neurogenic lineage GFP expression is strong and sparse enough to track single cells in vivo Adult neuron migration is well fit by a superdiffusive model Superdiffusive migration is sufficient to populate HVC in simulation