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bioRxiv · 10.1101/2020.10.31.363507

Focus-tunable microscope for imaging small neuronal processes in freely moving animals

Bagramyan, A.·Tabourin, L.·Rastqar, A.·Karimi, N.·Bretzner, F.·Galstian, T.
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Abstract

Miniature 1-photon microscopes have been widely used to image neuronal assemblies in the brain of freely moving animals over the last decade. However, these systems have important limitations for imaging in-depth fine neuronal structures. We present a novel subcellular imaging 1-photon device that uses an electrically tunable liquid crystal lens to enable a motion-free depth scan in the search of such structures. Our miniaturized microscope is compact (10 mm x 17 mm x 12 mm), lightweight ({approx} 1.4 g), provides fast acquisition rate (30-50 frames/second), high magnification (8.7x) and high resolution (1.4 m) that allow imaging of calcium activity of fine neuronal processes in deep brain regions during a wide range of behavioural tasks of freely moving mice.

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Bagramyan, A., Tabourin, L., Rastqar, A., Karimi, N., Bretzner, F., Galstian, T.. 2020-11-02. Focus-tunable microscope for imaging small neuronal processes in freely moving animals. https://doi.org/10.1101/2020.10.31.363507

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