title: Entorhinal Cortical Ocean Cells Encode Specific Contexts and Drive Context-Specific Fear Memory.
abstract: Forming distinct representations and memories of multiple contexts and episodes is thought to be a crucial function of the hippocampal-entorhinal cortical network. The hippocampal dentate gyrus (DG) and CA3 are known to contribute to these functions, but the role of the entorhinal cortex (EC) is poorly understood. Here, we show that Ocean cells, excitatory stellate neurons in the medial EC layer II projecting into DG and CA3, rapidly form a distinct representation of a novel context and drive context-specific activation of downstream CA3 cells as well as context-specific fear memory. In contrast, Island cells, excitatory pyramidal neurons in the medial EC layer II projecting into CA1, are indifferent to context-specific encoding or memory. On the other hand, Ocean cells are dispensable for temporal association learning, for which Island cells are crucial. Together, the two excitatory medial EC layer II inputs to the hippocampus have complementary roles in episodic memory.
authors.affiliation: RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kitamura
authors.affiliation: RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Chen
authors.initials: C
authors.lastname: Sun
authors.affiliation: RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Jared
authors.initials: J
authors.lastname: Martin
authors.affiliation: James H. Clark Center, Stanford University, Stanford, CA 94305, USA.
authors.forename: Lacey J
authors.initials: LJ
authors.lastname: Kitch
authors.affiliation: James H. Clark Center, Stanford University, Stanford, CA 94305, USA; CNC Program, Stanford University, Stanford, CA 94305, USA; Howard Hughes Medical Institute at Stanford University, Stanford, CA 94305, USA.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Schnitzer
authors.affiliation: RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute at MIT, Cambridge, MA 02139, USA. Electronic address: tonegawa@mit.edu.
authors.forename: Susumu
authors.initials: S
authors.lastname: Tonegawa
mesh_terms: D000818:Animals; D018728:Entorhinal Cortex / Q000166:cytology* / Q000502:physiology*; D005239:Fear / Q000502:physiology*; D008297:Male; D008568:Memory / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009434:Neural Pathways / Q000166:cytology / Q000502:physiology