Learning-Dependent Increases in Sleep Spindle Density

  title={Learning-Dependent Increases in Sleep Spindle Density},
  author={Steffen Gais and Matthias M{\"o}lle and Kay Helms and Jan Born},
  journal={The Journal of Neuroscience},
  pages={6830 - 6834}
Declarative memory consolidation is enhanced by sleep. In the investigation of underlying mechanisms, mainly rapid eye movement (REM) sleep and slow-wave sleep have been considered. More recently, sleep stage 2 with sleep spindles as a most prominent feature has received increasing attention. Specifically, in rats hippocampal ripples were found to occur in temporal proximity to cortical sleep spindles, indicating an information transfer between the hippocampus and neocortex, which is supposed… 

Figures and Tables from this paper

Elevated Sleep Spindle Density after Learning or after Retrieval in Rats
The present study reports the first indication of learning-associated increase in spindle density in the rat, providing an animal model to study the role of brain oscillations in memory consolidation during sleep and substantially extend findings in humans.
The Critical Role of Sleep Spindles in Hippocampal-Dependent Memory: A Pharmacology Study
A critical role of spindles in human hippocampal memory performance is demonstrated for the first time and gains in memory consolidation exceed sleep-alone or control conditions and demonstrate the potential for targeted, exceptional memory enhancement in healthy adults with pharmacologically modified sleep.
The memory function of sleep
Sleep has been identified as a state that optimizes the consolidation of newly acquired information in memory, depending on the specific conditions of learning and the timing of sleep, through specific patterns of neuromodulatory activity and electric field potential oscillations.
Sleep stage II contributes to the consolidation of declarative memories
Hippocampal memory consolidation during sleep: a comparison of mammals and birds
Avian sleep does not appear to be involved in transferring hippocampal memories to other brain regions, and the slow‐oscillation, the defining feature of mammalian and avian SWS, may serve a more general function independent of that related to coordinating the transfer of information from the hippocampus to the PFC in mammals.
Hippocampal Sharp Wave/Ripples during Sleep for Consolidation of Associative Memory
This study addresses the hypothesis that the fast oscillations known as ripples recorded in the CA1 region of the hippocampus during slow wave sleep (SWS) may provide a physiological substrate for long term memory consolidation by training rats in a spatial discrimination task.


The sequential hypothesis of the function of sleep
Memory consolidation during sleep: a neurophysiological perspective.
It is suggested that sleep patterns in the limbic system are essential for the preservation of experience-induced synaptic modifications, and the subcortical effects of hippocampal sharp wave bursts may be critical in the release of various hormones which, in turn, may affect synaptic plasticity.
Effects of early and late nocturnal sleep on priming and spatial memory.
It appears that earlySleep dominated by SWS facilitates consolidation of declarative memory whereas late sleep dominated by REM sleep facilitates consolidationof nondeclarativeMemory.
Effects of Early and Late Nocturnal Sleep on Declarative and Procedural Memory
The experiments for the first time dissociate specific effects of early and late sleep on two principal types of memory, declarative and procedural, in humans, and the benefit from sleep on recall depended on the phase of sleep and on the type of memory.
Impaired motor memory for a pursuit rotor task following Stage 2 sleep loss in college students
It was concluded that Stage 2 sleep, rather than REM sleep was the important stage of sleep for efficient memory processing of the pursuit rotor task.
Reactivation of Hippocampal Cell Assemblies: Effects of Behavioral State, Experience, and EEG Dynamics
Pattern reinstatement was strongest during sharp wave–ripple oscillations, suggesting that these events may reflect system convergence onto attractor states corresponding to previous experiences, and do not necessarily reflect persistence of an active memory.
Reactivation of hippocampal ensemble memories during sleep.
Recordings from large ensembles of hippocampal "place cells" in three rats showed that cells that fired together when the animal occupied particular locations in the environment exhibited an increased tendency to fire together during subsequent sleep, in comparison to sleep episodes preceding the behavioral tasks.
Neuromodulation: acetylcholine and memory consolidation
  • M. Hasselmo
  • Biology, Psychology
    Trends in Cognitive Sciences
  • 1999
Memory reprocessing in corticocortical and hippocampocortical neuronal ensembles.
Hippocampal cells that fire together during behaviour exhibit enhanced activity correlations during subsequent sleep, with some preservation of temporal order information, and traces of recent experience are re-expressed in both hippocampal and neocortical circuits during sleep.