Understanding how the brain computes signals from the outside world is one of the major frontiers in neurosciences. It is today possible to record and manipulate the activity of genetically defined neurons in behaving animals to generate and test hypothesis on how neuronal circuits function in physiological or pathological contexts.

2-photon microscopy is a method of choice to take advantage of these molecular tools to image (GCaMPs) or stimulate (opsins) neurons in awake and behaving animals. However, it usually operates on limited, thin, 2D planes which are not reflecting the 3D distribution of the neurons of interest in a brain volume.

Our project is to implement a core facility system enabling 2- photon Bessel beam imaging of calcium transients in neurons while simultaneously stimulating them using 3D holographic 2-photon photostimulation.

This project brings together biology groups across 4 neurosciences institutes and an expert group in neurophotonics, to build a microscope dedicated to the study of cortical circuits.