Brain Rhythms During Sleep and Memory Consolidation: Neurobiological Insights

Abstract

Sleep can benefit memory consolidation. The characterization of brain regions underlying memory consolidation during sleep, as well as their temporal interplay, reflected by specific patterns of brain electric activity, is surfacing. Here, we provide an overview of recent concepts and results on the mechanisms of sleep-related memory consolidation. The latest studies strongly impacting future directions of research in this field are highlighted.

Correlation between Alteration of Sharp-wave Ripple Coupled Cortical Oscillation and Long-term Memory Deficit in Alzheimer Disease Model Mice

“…High-frequency oscillations are relatively temporary events compared to low-frequency oscillations. Thus, fast waves can be located within a particular phase of slower waves, and this process is known to lead to the integration of neuronal population [ 15 , 16 ]. To investigate the phasic relationship between the SWR and coordinated delta oscillation, we analyzed the hippocampus and RSC delta phases corresponding to individual SWR outbreak points ( Fig.…”

“…Together with SWR, slow oscillation (SO) and spindle events detected in the cortex play an important role in memory consolidation. These oscillations tend to build temporal relationships with each other, indicating mutual information transfer between the hippocampus and cortex [ 14 - 17 , 21 ].…”

“…These results indicate that there might be a sequential mechanism in the episodic memory dysfunction of AD; however, there is still a lack of explanation for these symptoms.Appropriate communication between the hippocampus and cortices is critical for proper future use of encoded information. According to previous studies, this interplay is extensively executed during slow wave sleep (SWS), which is characterized by large-amplitude delta waves [14][15][16][17]. Neural components related to previous events are reactivated, corresponding synaptic connections are strengthened, and irrelevant ones are globally scaled down during the unique oscillations of SWS [18][19][20].…”

Manipulating neural activity and sleep-dependent memory consolidation

“…Studies on postlearning modulations of sleep brain rhythms and their distinct events (e. g., density, amplitude, duration of SPWRs, spindles or SOs), as compared to activity after nonlearning conditions, revealed temporally coordinated network and cellular activity. Concepts on the relevance for memory consolidation of temporally fine-tuned communication between brain regions were boosted by findings on the time-and phase-dependent occurrence (phase-amplitude coupling) of SPWRs and spindle activity relative to slower neural events (for reviews, see Girardeau and Zugaro, 2011;Marshall et al, 2020).…”

A neural circuit linking two sugar sensors regulates satiety-dependent fructose drive in Drosophila

“…MB-MP1 neurons of the mushroom bodies (MBs) also display calcium oscillations at a frequency around 0.1 Hz and are thought to signal the availability of energy required for long-term memory (LTM) formation (10,11). This 0.1-Hz frequency is notably slow compared to other characterized oscillations involved in visual and olfactory perception (12,13), motor coordination (14), memory (15,16), and sleep and consciousness (17,18). The slow frequency of energy sensing oscillations in flies may be a criterion for identifying functionally similar neurons.…”