Viral Injection and cranial window implantation for in vivo two-photon imaging

Two-photon (2P) imaging has proven to be a powerful tool for investigating neural structure and function both in brain slices and in intact systems. In vivo 2P imaging presents significant challenges in sample preparation, which are exacerbated in non-murine species. Here, we describe procedures for the effective virally mediated labeling of neurons and for the implantation of cranial windows for imaging. The procedures described here are applicable to a range of species, including mice, and are routinely used in ferrets and tree shrews to provide large-scale labeling of cortical volumes and high-quality imaging data.