Longitudinal two-photon calcium imaging with ultra-large cranial window for head-fixed mice

Neural activity is heterogeneous across different cortical areas and can change during learning. Here, we describe a protocol for longitudinal in vivo two-photon calcium imaging with an ultra-large cranial window that exposes most of the dorsal cortex in head-fixed mice. The large cranial window allows optical access to any dorsal cortical areas in individual mice. This protocol enables longitudinal tracking of neural activity from various cortical areas at cellular resolution to understand the cortical computations during behavioral tasks. For complete details on the use and execution of this protocol, please refer to Hattori et al. (2019), and Hattori and Komiyama, 2022a.