title: Two-photon calcium imaging in mice navigating a virtual reality environment.
abstract: In recent years, two-photon imaging has become an invaluable tool in neuroscience, as it allows for chronic measurement of the activity of genetically identified cells during behavior(1-6). Here we describe methods to perform two-photon imaging in mouse cortex while the animal navigates a virtual reality environment. We focus on the aspects of the experimental procedures that are key to imaging in a behaving animal in a brightly lit virtual environment. The key problems that arise in this experimental setup that we here address are: minimizing brain motion related artifacts, minimizing light leak from the virtual reality projection system, and minimizing laser induced tissue damage. We also provide sample software to control the virtual reality environment and to do pupil tracking. With these procedures and resources it should be possible to convert a conventional two-photon microscope for use in behaving mice.
authors.affiliation: Friedrich Miescher Institute for Biomedical Research; Max Planck Institute of Neurobiology.
authors.forename: Marcus
authors.initials: M
authors.lastname: Leinweber
authors.affiliation: Friedrich Miescher Institute for Biomedical Research; Max Planck Institute of Neurobiology.
authors.forename: Pawel
authors.initials: P
authors.lastname: Zmarz
authors.affiliation: Department of Biosystems Science and Engineering, ETH Zurich.
authors.forename: Peter
authors.initials: P
authors.lastname: Buchmann
authors.affiliation: Friedrich Miescher Institute for Biomedical Research.
authors.forename: Paul
authors.initials: P
authors.lastname: Argast
authors.affiliation: Max Planck Institute of Neurobiology.
authors.forename: Mark
authors.initials: M
authors.lastname: Hübener
authors.affiliation: Max Planck Institute of Neurobiology.
authors.forename: Tobias
authors.initials: T
authors.lastname: Bonhoeffer
authors.affiliation: Friedrich Miescher Institute for Biomedical Research; Max Planck Institute of Neurobiology; georg.keller@fmi.ch.
authors.forename: Georg B
authors.initials: GB
authors.lastname: Keller
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D002118:Calcium / Q000032:analysis*; D002540:Cerebral Cortex / Q000502:physiology*; D003399:Craniotomy / Q000379:methods; D005456:Fluorescent Dyes / Q000737:chemistry; D051379:Mice; D036641:Microscopy, Fluorescence, Multiphoton / Q000295:instrumentation / Q000379:methods*; D014584:User-Computer Interface
chemical_list: D005456:Fluorescent Dyes; D002118:Calcium