1. Structural Biology and Molecular Biophysics
  2. Neuroscience
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A large field of view two-photon mesoscope with subcellular resolution for in vivo imaging

  1. Nicholas James Sofroniew
  2. Daniel Flickinger
  3. Jonathon King
  4. Karel Svoboda  Is a corresponding author
  1. Janelia Research Campus, Howard Hughes Medical Institute, United States
  2. Vidrio Technologies, United States
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Cite this article as: eLife 2016;5:e14472 doi: 10.7554/eLife.14472


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.

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Author details

  1. Nicholas James Sofroniew

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    No competing interests declared.
  2. Daniel Flickinger

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    No competing interests declared.
  3. Jonathon King

    Vidrio Technologies, Ashburn, United States
    Competing interests
    No competing interests declared.
  4. Karel Svoboda

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    For correspondence
    Competing interests
    Karel Svoboda, Reviewing editor, eLife.


Animal experimentation: All procedures were in accordance with protocols approved by the Janelia Research Campus Institutional Animal Care and Use Committee. IACUC 14-115.

Reviewing Editor

  1. Fred Rieke, Howard Hughes Medical Institute, University of Washington, United States

Publication history

  1. Received: January 16, 2016
  2. Accepted: June 13, 2016
  3. Accepted Manuscript published: June 14, 2016 (version 1)
  4. Version of Record published: July 19, 2016 (version 2)


© 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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