title: Direct reactivation of a coherent neocortical memory of context.
abstract: Declarative memories are thought to be stored within anatomically distributed neuronal networks requiring the hippocampus; however, it is unclear how neocortical areas participate in memory at the time of encoding. Here, we use a c-fos-based genetic tagging system to selectively express the channelrhodopsin variant, ChEF, and optogenetically reactivate a specific neural ensemble in retrosplenial cortex (RSC) engaged by context fear conditioning. Artificial stimulation of RSC was sufficient to produce both context-specific behavior and downstream cellular activity commensurate with natural experience. Moreover, optogenetically but not contextually elicited responses were insensitive to hippocampal inactivation, suggesting that although the hippocampus is needed to coordinate activation by sensory cues, a higher-order cortical framework can independently subserve learned behavior, even shortly after learning.
authors.affiliation: Department of Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, 10550 North Torrey Pines Road, DNC 202, La Jolla, CA 92037, USA.
authors.forename: Kiriana K
authors.initials: KK
authors.lastname: Cowansage
authors.affiliation: Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, 710 Westwood Plaza, Los Angeles, CA 90095, USA.
authors.forename: Tristan
authors.initials: T
authors.lastname: Shuman
authors.affiliation: Department of Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, 10550 North Torrey Pines Road, DNC 202, La Jolla, CA 92037, USA; The Kellogg School of Science and Technology.
authors.forename: Blythe C
authors.initials: BC
authors.lastname: Dillingham
authors.affiliation: Department of Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, 10550 North Torrey Pines Road, DNC 202, La Jolla, CA 92037, USA.
authors.forename: Allene
authors.initials: A
authors.lastname: Chang
authors.affiliation: Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, 710 Westwood Plaza, Los Angeles, CA 90095, USA; UCLA Integrative Center for Learning and Memory; West Los Angeles VA Medical Center, 11301 Wilshire Boulevard, Los Angeles, CA 90073, USA.
authors.forename: Peyman
authors.initials: P
authors.lastname: Golshani
authors.affiliation: Department of Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, 10550 North Torrey Pines Road, DNC 202, La Jolla, CA 92037, USA. Electronic address: mmayford@scripps.edu.
authors.forename: Mark
authors.initials: M
authors.lastname: Mayford
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D003213:Conditioning, Psychological / Q000502:physiology; D003463:Cues; D005239:Fear / Q000502:physiology*; D006624:Hippocampus / Q000502:physiology; D007858:Learning / Q000502:physiology*; D008568:Memory / Q000502:physiology*; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D019579:Neocortex / Q000502:physiology*