title: Hippocampal neurogenesis regulates forgetting during adulthood and infancy.
abstract: Throughout life, new neurons are continuously added to the dentate gyrus. As this continuous addition remodels hippocampal circuits, computational models predict that neurogenesis leads to degradation or forgetting of established memories. Consistent with this, increasing neurogenesis after the formation of a memory was sufficient to induce forgetting in adult mice. By contrast, during infancy, when hippocampal neurogenesis levels are high and freshly generated memories tend to be rapidly forgotten (infantile amnesia), decreasing neurogenesis after memory formation mitigated forgetting. In precocial species, including guinea pigs and degus, most granule cells are generated prenatally. Consistent with reduced levels of postnatal hippocampal neurogenesis, infant guinea pigs and degus did not exhibit forgetting. However, increasing neurogenesis after memory formation induced infantile amnesia in these species.
authors.affiliation: Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, M5G 1X8, Canada.
authors.forename: Katherine G
authors.initials: KG
authors.lastname: Akers
authors.forename: Alonso
authors.initials: A
authors.lastname: Martinez-Canabal
authors.forename: Leonardo
authors.initials: L
authors.lastname: Restivo
authors.forename: Adelaide P
authors.initials: AP
authors.lastname: Yiu
authors.forename: Antonietta
authors.initials: A
authors.lastname: De Cristofaro
authors.forename: Hwa-Lin Liz
authors.initials: HL
authors.lastname: Hsiang
authors.forename: Anne L
authors.initials: AL
authors.lastname: Wheeler
authors.forename: Axel
authors.initials: A
authors.lastname: Guskjolen
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Niibori
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Shoji
authors.forename: Koji
authors.initials: K
authors.lastname: Ohira
authors.forename: Blake A
authors.initials: BA
authors.lastname: Richards
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Miyakawa
authors.forename: Sheena A
authors.initials: SA
authors.lastname: Josselyn
authors.forename: Paul W
authors.initials: PW
authors.lastname: Frankland
mesh_terms: D000647:Amnesia / Q000473:pathology* / Q000503:physiopathology*; D000818:Animals; D018891:Dentate Gyrus / Q000166:cytology; D005260:Female; D006168:Guinea Pigs; D006624:Hippocampus / Q000166:cytology*; D008297:Male; D008568:Memory; D051379:Mice; D008810:Mice, Inbred C57BL; D055495:Neurogenesis; D009474:Neurons / Q000166:cytology