Topic: spherical aberrations

Understanding cortical circuit computations requires recording methods with both unrestricted access to the entire cortical column as well as the ability to record from defined cell types in multiple cortical layers simultaneously. 3-photon excitation satisfies the first requirement but has only been applied to multi-layer acquisitions when multiplexed with 2-photon excitation by complex optical systems. We present a simple 3-photon imaging method which achieves simultaneous single-cell resolution imaging of two cortical planes at a maximum axial separation of 800 μm. This constitutes the larg