title: Levels of Interference in Long and Short-Term Memory Differentially Modulate Non-REM and REM Sleep.
abstract: It is commonly accepted that sleep is beneficial to memory processes, but it is still unclear if this benefit originates from improved memory consolidation or enhanced information processing. It has thus been proposed that sleep may also promote forgetting of undesirable and non-essential memories, a process required for optimization of cognitive resources. We tested the hypothesis that non-rapid eye movement sleep (NREMS) promotes forgetting of irrelevant information, more specifically when processing information in working memory (WM), while REM sleep (REMS) facilitates the consolidation of important information.
  
  
  
  We recorded sleep patterns of rats trained in a radial maze in three different tasks engaging either the long-term or short-term storage of information, as well as a gradual level of interference.
  
  
  
  We observed a transient increase in REMS amount on the day the animal learned the rule of a long-term/reference memory task (RM), and, in contrast, a positive correlation between the performance of rats trained in a WM task involving an important processing of interference and the amount of NREMS or slow wave activity. Various oscillatory events were also differentially modulated by the type of training involved. Notably, NREMS spindles and REMS rapid theta increase with RM training, while sharp-wave ripples increase with all types of training.
  
  
  
  These results suggest that REMS, but also rapid oscillations occurring during NREMS would be specifically implicated in the long-term memory in RM, whereas NREMS and slow oscillations could be involved in the forgetting of irrelevant information required for WM.
authors.affiliation: Forgetting and Cortical Dynamics, Lyon Neuroscience Research Center, University Lyon 1, Lyon, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Fraize
authors.affiliation: Forgetting and Cortical Dynamics, Lyon Neuroscience Research Center, University Lyon 1, Lyon, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Carponcy
authors.affiliation: Forgetting and Cortical Dynamics, Lyon Neuroscience Research Center, University Lyon 1, Lyon, France.
authors.forename: Mickaël Antoine
authors.initials: MA
authors.lastname: Joseph
authors.affiliation: Biphoton Internal Facility, Lyon Neuroscience Research Center, University Lyon 1, Lyon, France.
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Comte
authors.affiliation: Pathophysiology of the Neural Networks of the Sleep/Wake Cycle, Lyon Neuroscience Research Center, University Lyon 1, Lyon, France.
authors.forename: Pierre-Hervé
authors.initials: PH
authors.lastname: Luppi
authors.affiliation: Forgetting and Cortical Dynamics, Lyon Neuroscience Research Center, University Lyon 1, Lyon, France.|Pathophysiology of the Neural Networks of the Sleep/Wake Cycle, Lyon Neuroscience Research Center, University Lyon 1, Lyon, France.
authors.forename: Paul-Antoine
authors.initials: PA
authors.lastname: Libourel
authors.affiliation: Forgetting and Cortical Dynamics, Lyon Neuroscience Research Center, University Lyon 1, Lyon, France.|Biphoton Internal Facility, Lyon Neuroscience Research Center, University Lyon 1, Lyon, France.
authors.forename: Paul-Antoine
authors.initials: PA
authors.lastname: Salin
authors.affiliation: Forgetting and Cortical Dynamics, Lyon Neuroscience Research Center, University Lyon 1, Lyon, France.
authors.forename: Gaël
authors.initials: G
authors.lastname: Malleret
authors.affiliation: Forgetting and Cortical Dynamics, Lyon Neuroscience Research Center, University Lyon 1, Lyon, France.
authors.forename: Régis
authors.initials: R
authors.lastname: Parmentier
mesh_terms: D000818:Animals; D001288:Attention / Q000502:physiology; D004569:Electroencephalography; D018782:Maze Learning / Q000502:physiology*; D057567:Memory, Long-Term / Q000502:physiology*; D008570:Memory, Short-Term / Q000502:physiology*; D051381:Rats; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000503:physiopathology* / Q000523:psychology; D012895:Sleep, REM / Q000502:physiology*
keywords: REM sleep; forgetting; interference; oscillations; reference memory; sleep; slow-wave sleep; working memory