When the Locus Coeruleus Speaks Up in Sleep: Recent Insights, Emerging Perspectives

International Journal of Molecular Sciences, Journal Year: 2022, Volume and Issue: 23(9), P. 5028 - 5028

Published: April 30, 2022

For decades, numerous seminal studies have built our understanding of the locus coeruleus (LC), vertebrate brain’s principal noradrenergic system. Containing a numerically small but broadly efferent cell population, LC provides brain-wide modulation that optimizes network function in context attentive and flexible interaction with sensory environment. This review turns attention to LC’s roles during sleep. We show these go beyond down-scaled versions ones wakefulness. Novel dynamic assessments noradrenaline signaling activity uncover rich diversity patterns establish as an integral portion sleep regulation function. The could be involved beneficial functions for sleeping brain, even minute alterations its functionality may prove quintessential disorders.

Language: Английский

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Shaping overnight consolidation via slow-oscillation closed-loop targeted memory reactivation

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(44)

Published: Oct. 24, 2022

Sleep constitutes a privileged state for new memories to reactivate and consolidate. Previous work has demonstrated that consolidation can be bolstered experimentally either via delivery of reminder cues (targeted memory reactivation [TMR]) or noninvasive brain stimulation geared toward enhancing endogenous sleep rhythms. Here, we combined both approaches, controlling the timing TMR with respect ongoing slow-oscillation (SO) phases. Prior sleep, participants learned associations between unique words set repeating images (e.g., car) while hearing prototypical image sound engine starting). Memory performance on an immediate test vs. next morning quantified overnight consolidation. Importantly, two sounds were designated as cues, one cue delivered at SO UP states other DOWN states. A novel was used control condition. Behavioral results revealed significant reduction forgetting associated UP-state compared DOWN-state TMR. Electrophysiological showed cueing led enhancement followed by greater spindle power than cueing. Moreover, (and not DOWN-state) reinstatement target representations. Together, these unveil behavioral mechanistic effects delivering specific phases rhythms mark important step endeavor modulate during sleep.

Language: Английский

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A noradrenergic-hypothalamic neural substrate for stress-induced sleep disturbances

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(45)

Published: Nov. 4, 2022

In our daily life, we are exposed to uncontrollable and stressful events that disrupt sleep. However, the underlying neural mechanisms deteriorating quality of non-rapid eye movement sleep (NREMs) REM largely unknown. Here, show in mice acute psychosocial stress disrupts by increasing brief arousals (microarousals [MAs]), reducing spindles, impairing infraslow oscillations spindle band electroencephalogram during NREMs, while REMs. This poor was reflected an increased number calcium transients activity noradrenergic (NE) neurons locus coeruleus (LC) NREMs. Opto- chemogenetic LC-NE activation naïve is sufficient change microarchitecture similar stress. Conversely, chemogenetically inhibiting reduced MAs NREMs normalized their after Specifically projecting preoptic area hypothalamus (POA) decreased enhanced spindles REMs Optrode recordings revealed stimulating fibers POA indeed suppressed spiking activated inactivated MAs. Our findings reveal changes dynamics stress-regulatory negatively affect quality, partially through interaction with POA.

Language: Английский

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The human thalamus orchestrates neocortical oscillations during NREM sleep

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Sept. 5, 2022

A hallmark of non-rapid eye movement sleep is the coordinated interplay slow oscillations (SOs) and spindles. Traditionally, a cortico-thalamo-cortical loop suggested to coordinate these rhythms: neocortically-generated SOs trigger spindles in thalamus that are projected back neocortex. Here, we used intrathalamic recordings from human epilepsy patients test this canonical interplay. We show anterior precede neocortical (peak -50 ms), whereas concurrently-recorded mediodorsal led by +50 ms). Sleep spindles, detected both thalamic nuclei, preceded their counterparts -100 ms) were initiated during early phases SOs. Our findings indicate an active role organizing rhythms neocortex highlight functional diversity nuclei humans. The coordination could have broad implications for mechanisms underlying memory consolidation.

Language: Английский

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Sleep spindles track cortical learning patterns for memory consolidation

Current Biology, Journal Year: 2022, Volume and Issue: 32(11), P. 2349 - 2356.e4

Published: May 12, 2022

Memory consolidation-the transformation of labile memory traces into stable long-term representations-is facilitated by post-learning sleep. Computational and biophysical models suggest that sleep spindles may play a key mechanistic role for consolidation, igniting structural changes at cortical sites involved in prior learning. Here, we tested the resulting prediction are most pronounced over learning-related areas extent this learning-spindle overlap predicts behavioral measures consolidation. Using high-density scalp electroencephalography (EEG) polysomnography (PSG) healthy volunteers, first identified engaged during temporospatial associative task (power decreases alpha/beta frequency range, 6-20 Hz). Critically, found participant-specific topographies (i.e., spatial distributions) spindle amplitude correlated with learning topographies. Importantly, to which tracked patterns further predicted consolidation across participants. Our results provide empirical evidence tracking networks, thereby facilitating

Language: Английский

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