title: Cholinergic manipulations bidirectionally regulate object memory destabilization.
abstract: Consolidated memories can become destabilized and open to modification upon retrieval. Destabilization is most reliably prompted when novel information is present during memory reactivation. We hypothesized that the neurotransmitter acetylcholine (ACh) plays an important role in novelty-induced memory destabilization because of its established involvement in new learning. Accordingly, we investigated the effects of cholinergic manipulations in rats using an object recognition paradigm that requires reactivation novelty to destabilize object memories. The muscarinic receptor antagonist scopolamine, systemically or infused directly into the perirhinal cortex, blocked this novelty-induced memory destabilization. Conversely, systemic oxotremorine or carbachol, muscarinic receptor agonists, administered systemically or intraperirhinally, respectively, mimicked the destabilizing effect of novel information during reactivation. These bidirectional effects suggest a crucial influence of ACh on memory destabilization and the updating functions of reconsolidation. This is a hitherto unappreciated mnemonic role for ACh with implications for its potential involvement in cognitive flexibility and the dynamic process of long-term memory storage.
authors.affiliation: Department of Psychology and Neuroscience Program, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: Mikaela L
authors.initials: ML
authors.lastname: Stiver
authors.affiliation: Department of Psychology and Neuroscience Program, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: Derek L
authors.initials: DL
authors.lastname: Jacklin
authors.affiliation: Department of Psychology and Neuroscience Program, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: Krista A
authors.initials: KA
authors.lastname: Mitchnick
authors.affiliation: Department of Psychology and Neuroscience Program, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: Nevena
authors.initials: N
authors.lastname: Vicic
authors.affiliation: Department of Psychology and Neuroscience Program, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: Justine
authors.initials: J
authors.lastname: Carlin
authors.affiliation: Department of Psychology and Neuroscience Program, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: Matthew
authors.initials: M
authors.lastname: O'Hara
authors.affiliation: Department of Psychology and Neuroscience Program, University of Guelph, Guelph, Ontario N1G 2W1, Canada bwinters@uoguelph.ca.
authors.forename: Boyer D
authors.initials: BD
authors.lastname: Winters
mesh_terms: D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D002217:Carbachol / Q000494:pharmacology; D002540:Cerebral Cortex / Q000187:drug effects* / Q000502:physiology*; D008297:Male; D018721:Muscarinic Agonists / Q000494:pharmacology; D018727:Muscarinic Antagonists / Q000494:pharmacology; D009483:Neuropsychological Tests; D010095:Oxotremorine / Q000494:pharmacology; D020318:Rats, Long-Evans; D011976:Receptors, Muscarinic / Q000378:metabolism; D021641:Recognition, Psychology / Q000187:drug effects* / Q000502:physiology*; D012601:Scopolamine / Q000494:pharmacology
chemical_list: D018721:Muscarinic Agonists; D018727:Muscarinic Antagonists; D011976:Receptors, Muscarinic; D010095:Oxotremorine; D002217:Carbachol; D012601:Scopolamine; D000109:Acetylcholine