title: Artificial association of pre-stored information to generate a qualitatively new memory.
abstract: Memory is thought to be stored in the brain as an ensemble of cells activated during learning. Although optical stimulation of a cell ensemble triggers the retrieval of the corresponding memory, it is unclear how the association of information occurs at the cell ensemble level. Using optogenetic stimulation without any sensory input in mice, we found that an artificial association between stored, non-related contextual, and fear information was generated through the synchronous activation of distinct cell ensembles corresponding to the stored information. This artificial association shared characteristics with physiologically associated memories, such as N-methyl-D-aspartate receptor activity and protein synthesis dependence. These findings suggest that the association of information is achieved through the synchronous activity of distinct cell ensembles. This mechanism may underlie memory updating by incorporating novel information into pre-existing networks to form qualitatively new memories.
authors.affiliation: Department of Biochemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan; CREST, JST, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Ohkawa
authors.affiliation: Department of Biochemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan; CREST, JST, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Saitoh
authors.affiliation: Department of Biochemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan; CREST, JST, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
authors.forename: Akinobu
authors.initials: A
authors.lastname: Suzuki
authors.affiliation: Department of Biochemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan; CREST, JST, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
authors.forename: Shuhei
authors.initials: S
authors.lastname: Tsujimura
authors.affiliation: Department of Biochemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan; CREST, JST, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
authors.forename: Emi
authors.initials: E
authors.lastname: Murayama
authors.affiliation: Department of Biochemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan; CREST, JST, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
authors.forename: Sakurako
authors.initials: S
authors.lastname: Kosugi
authors.affiliation: Division of Animal Experimental Laboratory, Life Science Research Center, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Nishizono
authors.affiliation: Division of Animal Experimental Laboratory, Life Science Research Center, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
authors.forename: Mina
authors.initials: M
authors.lastname: Matsuo
authors.affiliation: Department of Neuroscience, Jikei University School of Medicine, Tokyo 105-8461, Japan.
authors.forename: Yukari
authors.initials: Y
authors.lastname: Takahashi
authors.affiliation: Department of Neuroscience, Jikei University School of Medicine, Tokyo 105-8461, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Nagase
authors.affiliation: Department of Neuroscience, Jikei University School of Medicine, Tokyo 105-8461, Japan.
authors.forename: Yae K
authors.initials: YK
authors.lastname: Sugimura
authors.affiliation: Department of Neuroscience, Jikei University School of Medicine, Tokyo 105-8461, Japan; Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan.
authors.forename: Ayako M
authors.initials: AM
authors.lastname: Watabe
authors.affiliation: Department of Neuroscience, Jikei University School of Medicine, Tokyo 105-8461, Japan; Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan.
authors.forename: Fusao
authors.initials: F
authors.lastname: Kato
authors.affiliation: Department of Biochemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan; CREST, JST, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan. Electronic address: inokuchi@med.u-toyama.ac.jp.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Inokuchi
mesh_terms: D000818:Animals; D005239:Fear / Q000502:physiology*; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D007858:Learning / Q000502:physiology; D008568:Memory / Q000502:physiology*; D051379:Mice; D062308:Optogenetics; D016194:Receptors, N-Methyl-D-Aspartate / Q000096:biosynthesis* / Q000378:metabolism
chemical_list: D016194:Receptors, N-Methyl-D-Aspartate