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bioRxiv · 10.1101/2024.10.21.619528

Opto2P-FCM: A MEMS based miniature two-photon microscope with two-photon patterned optogenetic stimulation

Futia, G. L.·Zohrabi, M.·McCullough, C.·Teel, A.·Simoes de Souza, F.·Oroke, R.·Miscles, E. J.·Ozbay, B. N.·Kilborn, K.·Bright, V. M.·Restrepo, D.·Gopinath, J. T.·Gibson, E. A.
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Abstract

Multiphoton microscopy combined with optogenetic photostimulation is a powerful technique in neuroscience enabling precise control of cellular activity to determine the neural basis of behavior in a live animal. Two-photon patterned photostimulation has taken this further by allowing interrogation at the individual neuron level. However, it remains a challenge to implement imaging of neural activity with spatially patterned two-photon photostimulation in a freely moving animal. We developed a miniature microscope for high resolution two-photon fluorescence imaging with patterned two-photon optogenetic stimulation. The design incorporates a MEMS scanner for two-photon imaging and a second beam path for patterned two-photon excitation in a compact and lightweight design that can be head-attached to a freely moving animal. We demonstrate cell-specific optogenetics and high resolution MEMS based two-photon imaging in a freely moving mouse. The new capabilities of this miniature microscope design can enable cell-specific studies of behavior that can only be done in freely moving animals.

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Futia, G. L., Zohrabi, M., McCullough, C., Teel, A., Simoes de Souza, F., Oroke, R., Miscles, E. J., Ozbay, B. N., Kilborn, K., Bright, V. M., Restrepo, D., Gopinath, J. T., Gibson, E. A.. 2024-10-22. Opto2P-FCM: A MEMS based miniature two-photon microscope with two-photon patterned optogenetic stimulation. https://doi.org/10.1101/2024.10.21.619528

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