title: A hippocampal network for spatial coding during immobility and sleep.
abstract: How does an animal know where it is when it stops moving? Hippocampal place cells fire at discrete locations as subjects traverse space, thereby providing an explicit neural code for current location during locomotion. In contrast, during awake immobility, the hippocampus is thought to be dominated by neural firing representing past and possible future experience. The question of whether and how the hippocampus constructs a representation of current location in the absence of locomotion has been unresolved. Here we report that a distinct population of hippocampal neurons, located in the CA2 subregion, signals current location during immobility, and does so in association with a previously unidentified hippocampus-wide network pattern. In addition, signalling of location persists into brief periods of desynchronization prevalent in slow-wave sleep. The hippocampus thus generates a distinct representation of current location during immobility, pointing to mnemonic processing specific to experience occurring in the absence of locomotion.
authors.affiliation: UCSF Center for Integrative Neuroscience and Department of Physiology, University of California San Francisco, California 94158, USA.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Kay
authors.affiliation: UCSF Center for Integrative Neuroscience and Department of Physiology, University of California San Francisco, California 94158, USA.
authors.forename: Marielena
authors.initials: M
authors.lastname: Sosa
authors.affiliation: UCSF Center for Integrative Neuroscience and Department of Physiology, University of California San Francisco, California 94158, USA.
authors.forename: Jason E
authors.initials: JE
authors.lastname: Chung
authors.affiliation: UCSF Center for Integrative Neuroscience and Department of Physiology, University of California San Francisco, California 94158, USA.
authors.forename: Mattias P
authors.initials: MP
authors.lastname: Karlsson
authors.affiliation: UCSF Center for Integrative Neuroscience and Department of Physiology, University of California San Francisco, California 94158, USA.
authors.forename: Margaret C
authors.initials: MC
authors.lastname: Larkin
authors.affiliation: UCSF Center for Integrative Neuroscience and Department of Physiology, University of California San Francisco, California 94158, USA.|Howard Hughes Medical Institute, University of California San Francisco, California 94158, USA.
authors.forename: Loren M
authors.initials: LM
authors.lastname: Frank
mesh_terms: D000200:Action Potentials; D000818:Animals; D006624:Hippocampus / Q000033:anatomy & histology / Q000166:cytology* / Q000502:physiology*; D008297:Male; D008959:Models, Neurological; D009068:Movement; D009474:Neurons / Q000502:physiology*; D009949:Orientation / Q000502:physiology*; D051381:Rats; D020318:Rats, Long-Evans; D012890:Sleep / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D065852:Spatial Memory / Q000502:physiology