Neurogenesis-mediated forgetting minimizes proactive interference

• Published in: Nature communications Vol. 7; no. 1; p. 10838
• Main Authors: Epp, Jonathan R., Silva Mera, Rudy, Köhler, Stefan, Josselyn, Sheena A., Frankland, Paul W.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 26.02.2016; Nature Publishing Group; Nature Portfolio
• Subjects: 14; 14/1; 14/63; 631/378/1595/1554; 631/378/1595/2639; 631/378/368; 64; 64/60; Animals; Association Learning; Cell Count; Dentate Gyrus - cytology; Discrimination Learning; Habituation, Psychophysiologic; Humanities and Social Sciences; Maze Learning - physiology; Memory - physiology; Mice; Mice, Transgenic; multidisciplinary; Nestin; Neurogenesis - physiology; Neurons; Promoter Regions, Genetic; Retention (Psychology) - physiology; Reversal Learning - physiology; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms10838

Established memories may interfere with the encoding of new memories, particularly when existing and new memories overlap in content. By manipulating levels of hippocampal neurogenesis, here we show that neurogenesis regulates this form of proactive interference. Increasing hippocampal neurogenesis weakens existing memories and, in doing so, facilitates the encoding of new, conflicting (but not non-conflicting) information in mice. Conversely, decreasing neurogenesis stabilizes existing memories, and impedes the encoding of new, conflicting information. These results suggest that reduced proactive interference is an adaptive benefit of neurogenesis-induced forgetting. New neurons are continuously produced throughout adulthood in the hippocampus. Here the authors provide evidence that adult hippocampal neurogenesis weakens existing memories, and facilitates the encoding of new, confliction information in mice.