ADAPT: Adaptive and predictive arbitrary point scanning two photon tomography

Two photon (2P) microscopy is an ideal technique to image deep inside tissues and organisms, with good sub-cellular axial resolution and without causing tissue damage. These advantages make 2P microscopy suited for intravital imaging, which can be used to investigate how neuronal circuits operate in normal and fail in diseased conditions. However, the current recording speeds of 2P microscopy are a limiting factor. They do not allow imaging at frame rates necessary to capture neuronal activity at hundreds or thousands images per second, especially not in three dimensions (3D). This project aims at ADAPTing the spectro-temporal laser imaging by diffractive excitation (SLIDE) technique previously introduced by the promoter, to enable fast neuroimaging. The specific ADAPTations include: 1/ acquiring volumetric data of layered neuronal structures at timescales that match functional processes; 2/ developing a dedicated near infrared source to SLIDE-2P-excite green genetically encoded calcium indicators; 3/ correcting wavefront distortions and 4/ introducing rapid adaptive scanning and sampling. ADAPT combines expertise in laser physics (S. Karpf), nanophotonics, nonlinear optics (L. Bonacina) and neurogastroenterology (P. Vanden Berghe) to develop this bespoke solution for fast 3D imaging, which will be applied to visualize activity patterns in the enteric nervous system, a multicellular network embedded in the gut wall that controls motility, absorption and secretion.