A large field of view two-photon mesoscope with subcellular resolution for in vivo imaging
Abstract
Imaging is used to map activity across populations of neurons. Microscopes with cellular resolution have small (< 1 millimeter) fields of view and cannot simultaneously image activity distributed across multiple brain areas. Typical large field of view microscopes do not resolve single cells, especially in the axial dimension. We developed a 2-photon random access mesoscope (2p-RAM) that allows high-resolution imaging anywhere within a volume spanning multiple brain areas (Φ 5 mm x 1 mm cylinder). 2p-RAM resolution is near diffraction limited (lateral, 0.66 μm, axial 4.09 μm at the center; excitation wavelength = 970 nm; numerical aperture = 0.6) over a large range of excitation wavelengths. A fast three-dimensional scanning system allows efficient sampling of neural activity in arbitrary regions of interest across the entire imaging volume. We illustrate the use of the 2p-RAM by imaging neural activity in multiple, non-contiguous brain areas in transgenic mice expressing protein calcium sensors.
Article and author information
Author details
Reviewing Editor
- Fred Rieke, Howard Hughes Medical Institute, University of Washington, United States
Ethics
Animal experimentation: All procedures were in accordance with protocols approved by the Janelia Research Campus Institutional Animal Care and Use Committee. IACUC 14-115.
Version history
- Received: January 16, 2016
- Accepted: June 13, 2016
- Accepted Manuscript published: June 14, 2016 (version 1)
- Version of Record published: July 19, 2016 (version 2)
Copyright
© 2016, Sofroniew et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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