RT Journal Article
SR Electronic
T1 Hippocampal Neurogenesis Regulates Forgetting During Adulthood and Infancy
JF Science
JO Science
FD American Association for the Advancement of Science
SP 598
OP 602
DO 10.1126/science.1248903
VO 344
IS 6184
A1 Akers, Katherine G.
A1 Martinez-Canabal, Alonso
A1 Restivo, Leonardo
A1 Yiu, Adelaide P.
A1 De Cristofaro, Antonietta
A1 Hsiang, Hwa-Lin (Liz)
A1 Wheeler, Anne L.
A1 Guskjolen, Axel
A1 Niibori, Yosuke
A1 Shoji, Hirotaka
A1 Ohira, Koji
A1 Richards, Blake A.
A1 Miyakawa, Tsuyoshi
A1 Josselyn, Sheena A.
A1 Frankland, Paul W.
YR 2014
UL http://science.sciencemag.org/content/344/6184/598.abstract
AB When examining the relationship between the production of new neurons in the hippocampus and memory, studies have generally first manipulated hippocampal neurogenesis and afterward investigated memory formation and found that new neurons help to encode new memories. However, when investigating how similar manipulations of neurogenesis impact established hippocampus-dependent memories, Akers et al. (p. 598; see the Perspective by Mongiat and Schinder) uncovered a role for neurogenesis in memory clearance. Thus, the continuous addition of new neurons both degrades existing information stored in hippocampal circuits and simultaneously provides substrates for new learning. 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.