Endogenous memory reactivation during sleep in humans is clocked by slow oscillation-spindle complexes

AbstractSleep is thought to support memory consolidation via reactivation of prior experiences, with particular electrophysiological sleep signatures (slow oscillations (SOs) and sleep spindles) gating the information flow between relevant brain areas. However, empirical evidence for a role of endogenous memory reactivation (i.e., without experimentally delivered memory cues) for consolidation in humans is lacking. Here, we devised a paradigm in which participants acquired associative memories before taking a nap. Multivariate decoding was then used to capture endogenous memory reactivation during non-rapid eye movement (NREM) sleep in surface EEG recordings. Our results reveal reactivation of learning material during SO-spindle complexes, with the precision of SO-spindle coupling predicting reactivation strength. Critically, reactivation strength (i.e. classifier evidence in favor of the previously studied stimulus category) in turn predicts the level of consolidation across participants. These results elucidate the memory function of sleep in humans and emphasize the importance of SOs and spindles in clocking endogenous consolidation processes.

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Endogenous memory reactivation during sleep in humans is clocked by slow oscillation-spindle complexes

10.1101/2020.09.16.299545 ◽

2020 ◽

Author(s):

Thomas Schreiner ◽

Marit Petzka ◽

Tobias Staudigl ◽

Bernhard P. Staresina

Keyword(s):

Memory Function ◽

Nrem Sleep ◽

Learning Material ◽

Associative Memories ◽

Brain Areas ◽

Slow Oscillations ◽

Memory Reactivation ◽

Function Of Sleep ◽

Prior Experiences

ABSTRACTSleep is thought to support memory consolidation via reactivation of prior experiences, with particular electrophysiological sleep signatures (slow oscillations (SOs) and sleep spindles) gating the information flow between relevant brain areas. However, empirical evidence for a role of endogenous memory reactivation (i.e., without experimentally delivered memory cues) for consolidation in humans is lacking. Here, we devised a paradigm in which participants acquired associative memories before taking a nap. Multivariate decoding was then used to capture endogenous memory reactivation during non-rapid eye movement (NREM) sleep. Results revealed reactivation of learning material during SO-spindle complexes, with the precision of SO-spindle coupling predicting reactivation strength. Critically, reactivation strength in turn predicted the level of consolidation across participants. These results elucidate the memory function of sleep in humans and emphasize the importance of SOs and spindles in clocking endogenous consolidation processes.

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Reactivating vocabularies in the elderly

10.1101/216283 ◽

2017 ◽

Author(s):

M.J. Cordi ◽

T. Schreiner ◽

B. Rasch

Keyword(s):

Older Adults ◽

Eye Movement ◽

Slow Wave ◽

National Science Foundation ◽

Memory Function ◽

Nrem Sleep ◽

Rapid Eye Movement ◽

Swiss National Science Foundation ◽

National Science ◽

Function Of Sleep

AbstractQuality of memory and sleep decline with age, but the mechanistic interactions underlying the memory function of sleep in older adults are still unknown. It is widely assumed that the beneficial effect of sleep on memory relies on reactivation during Non-rapid eye movement (NREM) sleep, and targeting these reactivations by cue re-exposure reliably improves memory in younger participants. Here we tested whether the reactivation mechanism during sleep is still functional in old age by applying targeted memory reactivation (TMR) during NREM sleep in healthy adults over 60 years. In contrast to previous studies in young participants, older adults’ memories do not generally benefit from TMR during NREM sleep. On an individual level, a subgroup of older adults still profited from cueing during sleep. These improvers tended to have a better sleep efficiency than non-improvers. In addition, the oscillatory results resembled those obtained in younger participants, involving increases in theta (~6Hz) and spindle (~13 Hz) power for remembered and gained words in a later time windows. In contrast, non-improvers showed no increases in theta activity and even strongly reduced spindle power for later gained vs. lost words. Our results suggest that reactivations during sleep might lose their functionality for memory in some older adults, while this mechanism is still intact in a subgroup of participants. Further studies need to examine more closely the determinants of preserving the memory function of sleep during healthy aging.Grant informationThe study was supported by grant of the Swiss National Science Foundation (SNSF) No. 100014_162388. T.S. is supported by a grant of the Swiss National Science Foundation (SNSF) No. P2ZHP1_164994.AbbreviationsN1 and N2Stage 1 and 2 sleepSWSSlow-wave sleepSWAslow-wave activityREMRapid eye movement sleepTSTTotal sleep timeTMRtargeted memory reactivation

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Theta bursts precede, and spindles follow, cortical and thalamic downstates in human NREM sleep

10.1101/260786 ◽

2018 ◽

Cited By ~ 3

Author(s):

Chris Gonzalez ◽

Rachel Mak-McCully ◽

Burke Rosen ◽

Sydney S. Cash ◽

Patrick Chauvel ◽

...

Keyword(s):

Brain Activity ◽

Intractable Epilepsy ◽

Nrem Sleep ◽

Human Cortex ◽

Scalp Eeg ◽

Temporal Coupling ◽

Healthy Cohort ◽

Eeg Recordings ◽

Generative Mechanisms

Abstract:Since their discovery, slow oscillations have been observed to group spindles during non-REM sleep. Previous studies assert that the slow oscillation downstate (DS) is preceded by slow spindles (10-12Hz), and followed by fast spindles (12-16Hz). Here, using both direct transcortical recordings in patients with intractable epilepsy (n=10, 8 female), as well as scalp EEG recordings from a healthy cohort (n=3, 1 female), we find in multiple cortical areas that both slow and fast spindles follow the DS. Although discrete oscillations do precede DSs, they are theta bursts (TB) centered at 5-8Hz. TBs were more pronounced for DSs in NREM stage N2 compared with N3. TB with similar properties occur in the thalamus, but unlike spindles they have no clear temporal relationship with cortical TB. These differences in corticothalamic dynamics, as well as differences between spindles and theta in coupling high frequency content, are consistent with NREM theta having separate generative mechanisms from spindles. The final inhibitory cycle of the TB coincides with the DS peak, suggesting that in N2, TB may help trigger the DS. Since the transition to N1 is marked by the appearance of theta, and the transition to N2 by the appearance of DS and thus spindles, a role of TB in triggering DS could help explain the sequence of electrophysiological events characterizing sleep. Finally, the coordinated appearance of spindles and DSs are implicated in memory consolidation processes, and the current findings redefine their temporal coupling with theta during NREM sleep.Significance StatementSleep is characterized by large slow waves which modulate brain activity. Prominent among these are ‘downstates,’ periods of a few tenths of a second when most cells stop firing, and ‘spindles,’ oscillations at about twelve times a second lasting for about a second. In this study, we provide the first detailed description of another kind of sleep wave: ‘theta bursts,’ a brief oscillation at about six cycles per second. We show, recording during natural sleep directly from the human cortex and thalamus, as well as on the human scalp, that theta bursts precede, and spindles follow downstates. Theta bursts may help trigger downstates in some circumstances, and organize cortical and thalamic activity so that memories can be consolidated during sleep.

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Administrasi Kurikulum

10.31219/osf.io/qxerd ◽

2020 ◽

Author(s):

haryati gustia syafly ◽

Hade Afriansyah

Keyword(s):

Learning Process ◽

Learning Material ◽

Content Learning

the article discusses about crriculum administration both in terms of meaning, proess and the role of the teacher andregulations that discuss the content learning material, and ways that can be used as guedilines in implementing the learning process

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Sex- and age-based differences in the effect of central serotonin on arterial blood pressure regulation

Journal of Applied Physiology ◽

10.1152/japplphysiol.00414.2020 ◽

2020 ◽

Vol 129 (6) ◽

pp. 1310-1323

Author(s):

Jennifer L. Magnusson ◽

Craig A. Emter ◽

Kevin J. Cummings

Keyword(s):

Blood Pressure ◽

Arterial Blood Pressure ◽

Nrem Sleep ◽

Blood Pressure Regulation ◽

Pressure Regulation ◽

Adult Rats ◽

Arterial Blood ◽

Serotonin Neurons ◽

Older Males

The role of serotonin in arterial blood pressure (ABP) regulation across states of vigilance is unknown. We hypothesized that adult rats devoid of CNS serotonin (TPH2−/−) have low ABP in wakefulness and NREM sleep, when serotonin neurons are active. However, TPH2−/− rats experience higher ABP than TPH2+/+ rats in wakefulness and REM only, a phenotype present only in older males and not females. CNS serotonin may be critical for preventing high ABP in males with aging.

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The role of EEG recordings in children undergoing cardiac surgery for congenital heart disease

Wiener Medizinische Wochenschrift ◽

10.1007/s10354-017-0576-0 ◽

2017 ◽

Vol 167 (11-12) ◽

pp. 251-255

Author(s):

Sascha Meyer ◽

Martin Poryo ◽

Mohammed Shatat ◽

Ludwig Gortner ◽

Hashim Abdul-Khaliq

Keyword(s):

Congenital Heart Disease ◽

Cardiac Surgery ◽

Heart Disease ◽

Congenital Heart ◽

Eeg Recordings

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Electroencephalographic Recordings of Focal Seizures in Patients Affected by Periventricular Nodular Heterotopia: Role of the Heterotopic Nodules in the Genesis of Epileptic Discharges

Journal of Child Neurology ◽

10.1177/08830738040190031701 ◽

2004 ◽

Vol 19 (3) ◽

pp. 369-377

Author(s):

Giorgio Battaglia ◽

Silvana Franceschetti ◽

Luisa Chiapparini ◽

Elena Freri ◽

Stefania Bassanini ◽

...

Keyword(s):

Brain Regions ◽

Periventricular Nodular Heterotopia ◽

Focal Seizures ◽

Ictal Eeg ◽

Epileptic Discharges ◽

Nodular Heterotopia ◽

Eeg Recordings ◽

Drug Resistant Epilepsy ◽

Video Eeg

Patients affected by periventricular nodular heterotopia are frequently characterized by focal drug-resistant epilepsy. To investigate the role of periventricular nodules in the genesis of seizures, we analyzed the electroencephalographic (EEG) features of focal seizures recorded by means of video-EEG in 10 patients affected by different types of periventricular nodular heterotopia and followed for prolonged periods of time at the epilepsy center of our institute. The ictal EEG recordings with surface electrodes revealed common features in all patients: all seizures originated from the brain regions where the periventricular nodular heterotopia were located; EEG patterns recorded on the leads exploring the periventricular nodular heterotopia were very similar both at the onset and immediately after the seizure's end in all patients. Our data suggest that seizures are generated by abnormal anatomic circuitries, including the heterotopic nodules and adjacent cortical areas. The major role of heterotopic neurons in the genesis and propagation of epileptic discharges must be taken into account when planning surgery for epilepsy in patients with periventricular nodular heterotopia. ( J Child Neurol 2005;20:369—377).

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