Two-photon miniaturized integrated neuro-optical photon system for neuronal circuits investigaiton in freely moving primates

Objective

The revolution in optogenetics began with the discovery of light-sensitive microbial opsins and their use to control neuronal activity with cell-type specificity, allowing for the first time functional mapping of the brain with cell type specificity. However, the wide-field illumination traditionally used in optogenetics synchronously activates large populations of neurons, lacking the precision needed to reproduce the complex, natural firing patterns of neural circuits. To overcome this limitation, Emiliani’s lab developed “circuit optogenetics,” combining computer-generated holography, temporal focusing, and two-photon excitation to achieve optogenetic control of circuits with millisecond-scale spatiotemporal precision, targeting single cells in depth. These methods have enabled unprecedentedly precise mapping and manipulation of neuronal circuits in mice, both head-fixed and freely moving. Building on advances from the HOLOVIS project—notably increased targeting capacity with ultra-fast sequential holographic targeting (FLiT), deeper brain layer access with three-photon (3P) holography, and performing circuit optogenetics in freely moving mice using two-photon holographic endoscopy—the current goal is to extend this precision to non-human primates. The project aims to develop 2P-MINOPS, an integrated and miniaturized two-photon system leveraging recent advances in miniaturized sources, modulators, and detectors. This platform will enable wireless optical study and manipulation of brain circuits in freely moving primates, paving the way for novel research into complex brain functions in models closer to humans.