title: Memory formation orchestrates the wiring of adult-born hippocampal neurons into brain circuits.
abstract: During memory formation, structural rearrangements of dendritic spines provide a mean to durably modulate synaptic connectivity within neuronal networks. New neurons generated throughout the adult life in the dentate gyrus of the hippocampus contribute to learning and memory. As these neurons become incorporated into the network, they generate huge numbers of new connections that modify hippocampal circuitry and functioning. However, it is yet unclear as to how the dynamic process of memory formation influences their synaptic integration into neuronal circuits. New memories are established according to a multistep process during which new information is first acquired and then consolidated to form a stable memory trace. Upon recall, memory is transiently destabilized and vulnerable to modification. Using contextual fear conditioning, we found that learning was associated with an acceleration of dendritic spines formation of adult-born neurons, and that spine connectivity becomes strengthened after memory consolidation. Moreover, we observed that afferent connectivity onto adult-born neurons is enhanced after memory retrieval, while extinction training induces a change of spine shapes. Together, these findings reveal that the neuronal activity supporting memory processes strongly influences the structural dendritic integration of adult-born neurons into pre-existing neuronal circuits. Such change of afferent connectivity is likely to impact the overall wiring of hippocampal network, and consequently, to regulate hippocampal function.
authors.affiliation: Research Center on Animal Cognition, Center for Integrative Biology, Université Paul Sabatier, UMR5169 CNRS, 118, route de Narbonne, 31062, Toulouse Cedex 9, France.
authors.forename: Petnoi
authors.initials: P
authors.lastname: Petsophonsakul
authors.affiliation: Research Center on Animal Cognition, Center for Integrative Biology, Université Paul Sabatier, UMR5169 CNRS, 118, route de Narbonne, 31062, Toulouse Cedex 9, France.
authors.forename: Kevin
authors.initials: K
authors.lastname: Richetin
authors.affiliation: Research Center on Animal Cognition, Center for Integrative Biology, Université Paul Sabatier, UMR5169 CNRS, 118, route de Narbonne, 31062, Toulouse Cedex 9, France.|Department of Physiology, Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia.
authors.forename: Trinovita
authors.initials: T
authors.lastname: Andraini
authors.affiliation: Stem Cell Laboratory for CNS Diseases Modeling, Department of Experimental Medical Science, Wallenberg Neuroscience Center, Lund Stem Cell Center and MultiPark, Lund University, BMC A10, 221 84, Lund, Sweden.
authors.forename: Laurent
authors.initials: L
authors.lastname: Roybon
authors.affiliation: Research Center on Animal Cognition, Center for Integrative Biology, Université Paul Sabatier, UMR5169 CNRS, 118, route de Narbonne, 31062, Toulouse Cedex 9, France. claire.rampon@univ-tlse3.fr.
authors.forename: Claire
authors.initials: C
authors.lastname: Rampon
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D003213:Conditioning, Psychological; D049229:Dendritic Spines / Q000378:metabolism / Q000502:physiology; D004558:Electric Stimulation; D005239:Fear; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D008164:Luminescent Proteins / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D008568:Memory; D008810:Mice, Inbred C57BL; D009434:Neural Pathways / Q000378:metabolism / Q000502:physiology; D056347:Neuroanatomical Tract-Tracing Techniques; D055495:Neurogenesis; D009474:Neurons / Q000378:metabolism / Q000502:physiology*; D013997:Time Factors; D000097573:Red Fluorescent Protein
chemical_list: D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins; D000097573:Red Fluorescent Protein; C485184:enhanced green fluorescent protein
keywords: Adult hippocampal neurogenesis; Dendritic spine; Fear conditioning; Learning; Memory