title: Impaired sequential egocentric and allocentric memories in forebrain-specific-NMDA receptor knock-out mice during a new task dissociating strategies of navigation.
abstract: The hippocampus is considered to play a role in allocentric but not in egocentric spatial learning. How does this view fit with the emerging evidence that the hippocampus and possibly related cortical areas are necessary for episodic-like memory, i.e., in all situations in which events need to be spatially or sequentially organized? Are NMDA receptor-dependent mechanisms crucial for the acquisition of spatiotemporal relationships? To address this issue, we used knock-out (KO) mice lacking hippocampal CA1 NMDA receptors and presenting a reduction of these receptors in the deep cortical layers (NR1-KO mice). A new task (the starmaze) was designed, allowing us to distinguish allocentric and sequential-egocentric memories. NR1-KO mice were impaired in acquiring both types of memory. Our findings suggest that memories composed of multiple spatiotemporal events require intact NMDA receptors-dependent mechanisms in CA1 and possibly in the deep cortical layers.
authors.affiliation: Collège de France, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7152, Laboratoire de Physiologie de la Perception et de l'Action, F-75005 Paris, France. laure.rondi-reig@college-de-france.fr
authors.forename: Laure
authors.initials: L
authors.lastname: Rondi-Reig
authors.forename: Géraldine H
authors.initials: GH
authors.lastname: Petit
authors.forename: Christine
authors.initials: C
authors.lastname: Tobin
authors.forename: Susumu
authors.initials: S
authors.lastname: Tonegawa
authors.forename: Jean
authors.initials: J
authors.lastname: Mariani
authors.forename: Alain
authors.initials: A
authors.lastname: Berthoz
mesh_terms: D000818:Animals; D005838:Genotype; D006624:Hippocampus / Q000502:physiology*; D007858:Learning / Q000502:physiology*; D018782:Maze Learning / Q000502:physiology*; D008568:Memory / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D009043:Motor Activity / Q000502:physiology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D012016:Reference Values
chemical_list: C409466:NR1 NMDA receptor; D016194:Receptors, N-Methyl-D-Aspartate