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Höller Y, Eyjólfsdóttir S, Van Schalkwijk FJ, Trinka E. The effects of slow wave sleep characteristics on semantic, episodic, and procedural memory in people with epilepsy. Front Pharmacol 2024; 15:1374760. [PMID: 38725659 PMCID: PMC11079234 DOI: 10.3389/fphar.2024.1374760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 04/04/2024] [Indexed: 05/12/2024] Open
Abstract
Slow wave sleep (SWS) is highly relevant for verbal and non-verbal/spatial memory in healthy individuals, but also in people with epilepsy. However, contradictory findings exist regarding the effect of seizures on overnight memory retention, particularly relating to procedural and non-verbal memory, and thorough examination of episodic memory retention with ecologically valid tests is missing. This research explores the interaction of SWS duration with epilepsy-relevant factors, as well as the relation of spectral characteristics of SWS on overnight retention of procedural, verbal, and episodic memory. In an epilepsy monitoring unit, epilepsy patients (N = 40) underwent learning, immediate and 12 h delayed testing of memory retention for a fingertapping task (procedural memory), a word-pair task (verbal memory), and an innovative virtual reality task (episodic memory). We used multiple linear regression to examine the impact of SWS duration, spectral characteristics of SWS, seizure occurrence, medication, depression, seizure type, gender, and epilepsy duration on overnight memory retention. Results indicated that none of the candidate variables significantly predicted overnight changes for procedural memory performance. For verbal memory, the occurrence of tonic-clonic seizures negatively impacted memory retention and higher psychoactive medication load showed a tendency for lower verbal memory retention. Episodic memory was significantly impacted by epilepsy duration, displaying a potential nonlinear impact with a longer duration than 10 years negatively affecting memory performance. Higher drug load of anti-seizure medication was by tendency related to better overnight retention of episodic memory. Contrary to expectations longer SWS duration showed a trend towards decreased episodic memory performance. Analyses on associations between memory types and EEG band power during SWS revealed lower alpha-band power in the frontal right region as significant predictor for better episodic memory retention. In conclusion, this research reveals that memory modalities are not equally affected by important epilepsy factors such as duration of epilepsy and medication, as well as SWS spectral characteristics.
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Affiliation(s)
- Yvonne Höller
- Faculty of Psychology, University of Akureyri, Akureyri, Iceland
| | | | - Frank Jasper Van Schalkwijk
- Hertie-Institute for Clinical Brain Research, Center for Neurology, University Medical Center Tübingen, Tübingen, Germany
| | - Eugen Trinka
- Department of Neurology, Christian Doppler University Hospital, Member of the European Reference Network EpiCARE, Neuroscience Institute, Paracelsus Medical University and Centre for Cognitive Neuroscience Salzburg, Salzburg, Austria
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2
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Kumral D, Matzerath A, Leonhart R, Schönauer M. Spindle-dependent memory consolidation in healthy adults: A meta-analysis. Neuropsychologia 2023; 189:108661. [PMID: 37597610 DOI: 10.1016/j.neuropsychologia.2023.108661] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 06/23/2023] [Accepted: 08/12/2023] [Indexed: 08/21/2023]
Abstract
Accumulating evidence suggests a central role for sleep spindles in the consolidation of new memories. However, no meta-analysis of the association between sleep spindles and memory performance has been conducted so far. Here, we report meta-analytical evidence for spindle-memory associations and investigate how multiple factors, including memory type, spindle type, spindle characteristics, and EEG topography affect this relationship. The literature search yielded 53 studies reporting 1427 effect sizes, resulting in a small to moderate effect for the average association. We further found that spindle-memory associations were significantly stronger for procedural memory than for declarative memory. Neither spindle types nor EEG scalp topography had an impact on the strength of the spindle-memory relation, but we observed a distinct functional role of global and fast sleep spindles, especially for procedural memory. We also found a moderation effect of spindle characteristics, with power showing the largest effect sizes. Collectively, our findings suggest that sleep spindles are involved in learning, thereby representing a general physiological mechanism for memory consolidation.
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Affiliation(s)
- Deniz Kumral
- Institute of Psychology, Neuropsychology, University of Freiburg, Freiburg Im Breisgau, Germany; Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
| | - Alina Matzerath
- Institute of Psychology, Neuropsychology, University of Freiburg, Freiburg Im Breisgau, Germany
| | - Rainer Leonhart
- Institute of Psychology, Social Psychology and Methodology, University of Freiburg, Freiburg Im Breisgau, Germany
| | - Monika Schönauer
- Institute of Psychology, Neuropsychology, University of Freiburg, Freiburg Im Breisgau, Germany; Bernstein Center Freiburg, Freiburg Im Breisgau, Germany
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3
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Kersanté F, Purple RJ, Jones MW. The GABA A receptor modulator zolpidem augments hippocampal-prefrontal coupling during non-REM sleep. Neuropsychopharmacology 2023; 48:594-604. [PMID: 35717464 PMCID: PMC9938179 DOI: 10.1038/s41386-022-01355-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 05/25/2022] [Accepted: 05/27/2022] [Indexed: 01/16/2023]
Abstract
Benzodiazepines and 'Z-drugs' (including zolpidem and zopiclone) are GABAA receptor (GABAAR) positive modulators commonly prescribed as hypnotics to treat insomnia and/or anxiety. However, alongside sedation, augmenting GABAAR function may also alter coordinated neuronal activity during sleep, thereby influencing sleep-dependent processes including memory consolidation. We used simultaneous recordings of neural population activity from the medial prelimbic cortex (PrL) and CA1 of the dorsal hippocampus (dCA1) of naturally sleeping rats to detail the effects of zolpidem on network activity during the cardinal oscillations of non-REM sleep. For comparison, we also characterized the effects of diazepam and 4,5,6,7-tetrahydroisoxazolo(5,4-c)pyridin-3-ol (THIP/gaboxadol), which acts predominantly at extra-synaptic GABAARs. Zolpidem and THIP significantly increased the amplitudes of slow-waves, which were attenuated by diazepam. Zolpidem increased hippocampal ripple density whereas diazepam decreased both ripple density and intrinsic frequency. While none of the drugs affected thalamocortical spindles in isolation, zolpidem augmented the temporal coordination between slow-waves and spindles. At the cellular level, analyses of spiking activity from 523 PrL and 579 dCA1 neurons revealed that zolpidem significantly enhanced synchronized pauses in cortical firing during slow-wave down states, while increasing correlated activity within and between dCA1 and PrL populations. Of the drugs compared here, zolpidem was unique in augmenting coordinated activity within and between hippocampus and neocortex during non-REM sleep. Zolpidem's enhancement of hippocampal-prefrontal coupling may reflect the cellular basis of its potential to modulate offline memory processing.
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Affiliation(s)
- Flavie Kersanté
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, UK
| | - Ross J Purple
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, UK
| | - Matthew W Jones
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, UK.
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4
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Zeller CJ, Züst MA, Wunderlin M, Nissen C, Klöppel S. The promise of portable remote auditory stimulation tools to enhance slow-wave sleep and prevent cognitive decline. J Sleep Res 2023:e13818. [PMID: 36631001 DOI: 10.1111/jsr.13818] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 12/13/2022] [Accepted: 12/14/2022] [Indexed: 01/13/2023]
Abstract
Dementia is the seventh leading cause of mortality, and a major source of disability and dependency in older individuals globally. Cognitive decline (and, to a lesser extent, normal ageing) are associated with sleep fragmentation and loss of slow-wave sleep. Evidence suggests a bidirectional causal link between these losses. Phase-locked auditory stimulation has emerged as a promising non-invasive tool to enhance slow-wave sleep, potentially ameliorating cognitive decline. In laboratory settings, auditory stimulation is usually supervised by trained experts. Different algorithms (simple amplitude thresholds, topographic correlation, sine-wave fitting, phase-locked loop, and phase vocoder) are used to precisely target auditory stimulation to a desired phase of the slow wave. While all algorithms work well in younger adults, the altered sleep physiology of older adults and particularly those with neurodegenerative disorders requires a tailored approach that can adapt to older adults' fragmented sleep and reduced amplitudes of slow waves. Moreover, older adults might require a continuous intervention that is not feasible in laboratory settings. Recently, several auditory stimulation-capable portable devices ('Dreem®', 'SmartSleep®' and 'SleepLoop®') have been developed. We discuss these three devices regarding their potential as tools for science, and as clinical remote-intervention tools to combat cognitive decline. Currently, SleepLoop® shows the most promise for scientific research in older adults due to high transparency and customizability but is not commercially available. Studies evaluating down-stream effects on cognitive abilities, especially in patient populations, are required before a portable auditory stimulation device can be recommended as a clinical preventative remote-intervention tool.
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Affiliation(s)
- Céline J Zeller
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland
| | - Marc A Züst
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland
| | - Marina Wunderlin
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland
| | - Christoph Nissen
- University Hospital of Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland.,Division of Psychiatric Specialties, Geneva University Hospitals (HUG), Geneva, Switzerland
| | - Stefan Klöppel
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland
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5
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Donnelly NA, Bartsch U, Moulding HA, Eaton C, Marston H, Hall JH, Hall J, Owen MJ, van den Bree MBM, Jones MW. Sleep EEG in young people with 22q11.2 deletion syndrome: A cross-sectional study of slow-waves, spindles and correlations with memory and neurodevelopmental symptoms. eLife 2022; 11:75482. [PMID: 36039635 PMCID: PMC9477499 DOI: 10.7554/elife.75482] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 08/12/2022] [Indexed: 11/20/2022] Open
Abstract
Background Young people living with 22q11.2 Deletion Syndrome (22q11.2DS) are at increased risk of schizophrenia, intellectual disability, attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). In common with these conditions, 22q11.2DS is also associated with sleep problems. We investigated whether abnormal sleep or sleep-dependent network activity in 22q11.2DS reflects convergent, early signatures of neural circuit disruption also evident in associated neurodevelopmental conditions. Methods In a cross-sectional design, we recorded high-density sleep EEG in young people (6-20 years) with 22q11.2DS (n=28) and their unaffected siblings (n=17), quantifying associations between sleep architecture, EEG oscillations (spindles and slow waves) and psychiatric symptoms. We also measured performance on a memory task before and after sleep. Results 22q11.2DS was associated with significant alterations in sleep architecture, including a greater proportion of N3 sleep and lower proportions of N1 and REM sleep than in siblings. During sleep, deletion carriers showed broadband increases in EEG power with increased slow-wave and spindle amplitudes, increased spindle frequency and density, and stronger coupling between spindles and slow-waves. Spindle and slow-wave amplitudes correlated positively with overnight memory in controls, but negatively in 22q11.2DS. Mediation analyses indicated that genotype effects on anxiety, ADHD and ASD were partially mediated by sleep EEG measures. Conclusions This study provides a detailed description of sleep neurophysiology in 22q11.2DS, highlighting alterations in EEG signatures of sleep which have been previously linked to neurodevelopment, some of which were associated with psychiatric symptoms. Sleep EEG features may therefore reflect delayed or compromised neurodevelopmental processes in 22q11.2DS, which could inform our understanding of the neurobiology of this condition and be biomarkers for neuropsychiatric disorders. Funding This research was funded by a Lilly Innovation Fellowship Award (UB), the National Institute of Mental Health (NIMH 5UO1MH101724; MvdB), a Wellcome Trust Institutional Strategic Support Fund (ISSF) award (MvdB), the Waterloo Foundation (918-1234; MvdB), the Baily Thomas Charitable Fund (2315/1; MvdB), MRC grant Intellectual Disability and Mental Health: Assessing Genomic Impact on Neurodevelopment (IMAGINE) (MR/L011166/1; JH, MvdB and MO), MRC grant Intellectual Disability and Mental Health: Assessing Genomic Impact on Neurodevelopment 2 (IMAGINE-2) (MR/T033045/1; MvdB, JH and MO); Wellcome Trust Strategic Award 'Defining Endophenotypes From Integrated Neurosciences' Wellcome Trust (100202/Z/12/Z MO, JH). NAD was supported by a National Institute for Health Research Academic Clinical Fellowship in Mental Health and MWJ by a Wellcome Trust Senior Research Fellowship in Basic Biomedical Science (202810/Z/16/Z). CE and HAM were supported by Medical Research Council Doctoral Training Grants (C.B.E. 1644194, H.A.M MR/K501347/1). HMM and UB were employed by Eli Lilly & Co during the study; HMM is currently an employee of Boehringer Ingelheim Pharma GmbH & Co KG. The views and opinions expressed are those of the author(s), and not necessarily those of the NHS, the NIHR or the Department of Health funders.
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Affiliation(s)
- Nicholas A Donnelly
- Centre for Academic Mental Health, University of Bristol, Bristol, United Kingdom.,Avon and Wiltshire Partnership NHS Mental Health Trust, Avon, United Kingdom
| | - Ullrich Bartsch
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, United Kingdom.,Translational Neuroscience, Eli Lilly, Windlesham, United States
| | - Hayley A Moulding
- Medical Research Council Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, United Kingdom
| | - Christopher Eaton
- Medical Research Council Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, United Kingdom
| | - Hugh Marston
- Translational Neuroscience, Eli Lilly, Windlesham, United States
| | - Jessica H Hall
- Medical Research Council Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, United Kingdom
| | - Jeremy Hall
- Medical Research Council Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, United Kingdom
| | - Michael J Owen
- Medical Research Council Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, United Kingdom
| | - Marianne B M van den Bree
- Medical Research Council Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, United Kingdom
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6
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Hamel R, Demers O, Lepage JF, Bernier PM. The Effects of Post-Learning Alcohol Ingestion on Human Motor Memory Consolidation. Eur J Neurosci 2022; 56:4600-4618. [PMID: 35841189 PMCID: PMC9544401 DOI: 10.1111/ejn.15772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 07/07/2022] [Indexed: 11/27/2022]
Abstract
The neurochemical mechanisms underlying motor memory consolidation remain largely unknown. Based on converging work showing that ethyl alcohol retrogradely enhances declarative memory consolidation, this work tested the hypothesis that post‐learning alcohol ingestion would enhance motor memory consolidation. In a within‐subject and fully counterbalanced design, participants (n = 24; 12M; 12F) adapted to a gradually introduced visual deviation and ingested, immediately after adaptation, a placebo (PBO), a medium (MED) or high (HIGH) dose of alcohol. The alcohol doses were bodyweight‐ and gender‐controlled to yield peak breath alcohol concentrations of 0.00% in the PBO, ~0.05% in the MED and ~0.095% in the HIGH condition. Retention was evaluated 24 h later through reach aftereffects when participants were sober. The results revealed that retention levels were neither significantly nor meaningfully different in both the MED and HIGH conditions as compared to PBO (all absolute Cohen's dz values < ~0.2; small to negligible effects), indicating that post‐learning alcohol ingestion did not alter motor memory consolidation. Given alcohol's known pharmacological GABAergic agonist and NMDA antagonist properties, one possibility is that these neurochemical mechanisms do not decisively contribute to motor memory consolidation. As converging work demonstrated alcohol's retrograde enhancement of declarative memory, the present results suggest that distinct neurochemical mechanisms underlie declarative and motor memory consolidation. Elucidating the neurochemical mechanisms underlying the consolidation of different memory systems may yield insights into the effects of over‐the‐counter drugs on everyday learning and memory but also inform the development of pharmacological interventions seeking to alter human memory consolidation.
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Affiliation(s)
- R Hamel
- Département de kinanthropologie, Faculté des sciences de l'activité physique, Université de Sherbrooke, Québec, Canada.,Département de pédiatrie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Québec, Canada.,Centre de recherche du Centre hospitalier de l'Université de Sherbrooke, Québec, Canada
| | - O Demers
- Département de kinanthropologie, Faculté des sciences de l'activité physique, Université de Sherbrooke, Québec, Canada.,Département de pédiatrie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Québec, Canada.,Centre de recherche du Centre hospitalier de l'Université de Sherbrooke, Québec, Canada
| | - J F Lepage
- Département de pédiatrie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Québec, Canada.,Centre de recherche du Centre hospitalier de l'Université de Sherbrooke, Québec, Canada
| | - P M Bernier
- Département de kinanthropologie, Faculté des sciences de l'activité physique, Université de Sherbrooke, Québec, Canada.,Centre de recherche du Centre hospitalier de l'Université de Sherbrooke, Québec, Canada
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7
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Leong CWY, Leow JWS, Grunstein RR, Naismith SL, Teh JZ, D’Rozario AL, Saini B. A systematic scoping review of the effects of central nervous system active drugs on sleep spindles and sleep-dependent memory consolidation. Sleep Med Rev 2022; 62:101605. [DOI: 10.1016/j.smrv.2022.101605] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 01/15/2022] [Accepted: 01/26/2022] [Indexed: 11/26/2022]
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8
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Carbone J, Bibián C, Reischl P, Born J, Forcato C, Diekelmann S. The effect of zolpidem on targeted memory reactivation during sleep. Learn Mem 2021; 28:307-318. [PMID: 34400532 PMCID: PMC8372567 DOI: 10.1101/lm.052787.120] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 07/07/2021] [Indexed: 01/05/2023]
Abstract
According to the active system consolidation theory, memory consolidation during sleep relies on the reactivation of newly encoded memory representations. This reactivation is orchestrated by the interplay of sleep slow oscillations, spindles, and theta, which are in turn modulated by certain neurotransmitters like GABA to enable long-lasting plastic changes in the memory store. Here we asked whether the GABAergic system and associated changes in sleep oscillations are functionally related to memory reactivation during sleep. We administered the GABAA agonist zolpidem (10 mg) in a double-blind placebo-controlled study. To specifically focus on the effects on memory reactivation during sleep, we experimentally induced such reactivations by targeted memory reactivation (TMR) with learning-associated reminder cues presented during post-learning slow-wave sleep (SWS). Zolpidem significantly enhanced memory performance with TMR during sleep compared with placebo. Zolpidem also increased the coupling of fast spindles and theta to slow oscillations, although overall the power of slow spindles and theta was reduced compared with placebo. In an uncorrected exploratory analysis, memory performance was associated with slow spindle responses to TMR in the zolpidem condition, whereas it was associated with fast spindle responses in placebo. These findings provide tentative first evidence that GABAergic activity may be functionally implicated in memory reactivation processes during sleep, possibly via its effects on slow oscillations, spindles and theta as well as their interplay.
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Affiliation(s)
- Julia Carbone
- Institute of Medical Psychology and Behavioural Neurobiology, University of Tübingen, 72076 Tübingen, Germany
- Graduate Training Centre of Neuroscience, International Max Planck Research School, University of Tübingen, 72076 Tübingen, Germany
| | - Carlos Bibián
- Institute of Medical Psychology and Behavioural Neurobiology, University of Tübingen, 72076 Tübingen, Germany
- Graduate Training Centre of Neuroscience, International Max Planck Research School, University of Tübingen, 72076 Tübingen, Germany
| | - Patrick Reischl
- Institute of Medical Psychology and Behavioural Neurobiology, University of Tübingen, 72076 Tübingen, Germany
| | - Jan Born
- Institute of Medical Psychology and Behavioural Neurobiology, University of Tübingen, 72076 Tübingen, Germany
- Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, 72076 Tübingen, Germany
| | - Cecilia Forcato
- Laboratorio de Sueño y Memoria, Departamento de Ciencias de la Vida, Instituto Tecnológico de Buenos Aires (ITBA), Buenos Aires C1106ACD, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Buenos Aires C1425FQB, Argentina
| | - Susanne Diekelmann
- Institute of Medical Psychology and Behavioural Neurobiology, University of Tübingen, 72076 Tübingen, Germany
- Department of Psychiatry and Psychotherapy, University Hospital Tübingen, 72076 Tübingen, Germany
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9
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Zahed H, Zuzuarregui JRP, Gilron R, Denison T, Starr PA, Little S. The Neurophysiology of Sleep in Parkinson's Disease. Mov Disord 2021; 36:1526-1542. [PMID: 33826171 DOI: 10.1002/mds.28562] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 02/02/2021] [Accepted: 02/16/2021] [Indexed: 12/14/2022] Open
Abstract
Sleep disturbances are among the most common nonmotor complications of Parkinson's disease (PD), can present in prodromal stages, and progress with advancing disease. In addition to being a symptom of neurodegeneration, sleep disturbances may also contribute to disease progression. Currently, limited options exist to modulate sleep disturbances in PD. Studying the neurophysiological changes that affect sleep in PD at the cortical and subcortical level may yield new insights into mechanisms for reversal of sleep disruption. In this article, we review cortical and subcortical recording studies of sleep in PD with a particular focus on dissecting reported electrophysiological changes. These studies show that slow-wave sleep and rapid eye movement sleep are both notably disrupted in PD. We further explore the impact of these electrophysiological changes and discuss the potential for targeting sleep via stimulation therapy to modify PD-related motor and nonmotor symptoms. © 2021 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Hengameh Zahed
- Department of Neurology, University of California, San Francisco, San Francisco, California, USA
| | | | - Ro'ee Gilron
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, California, USA
| | - Timothy Denison
- Institute of Biomedical Engineering and MRC Brain Network Dynamics Unit, University of Oxford, Oxford, UK
| | - Philip A Starr
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, California, USA
| | - Simon Little
- Department of Neurology, University of California, San Francisco, San Francisco, California, USA
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10
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Ruch S, Fehér K, Homan S, Morishima Y, Mueller SM, Mueller SV, Dierks T, Grieder M. Bi-Temporal Anodal Transcranial Direct Current Stimulation during Slow-Wave Sleep Boosts Slow-Wave Density but Not Memory Consolidation. Brain Sci 2021; 11:brainsci11040410. [PMID: 33805063 PMCID: PMC8064104 DOI: 10.3390/brainsci11040410] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 03/15/2021] [Accepted: 03/22/2021] [Indexed: 12/31/2022] Open
Abstract
Slow-wave sleep (SWS) has been shown to promote long-term consolidation of episodic memories in hippocampo–neocortical networks. Previous research has aimed to modulate cortical sleep slow-waves and spindles to facilitate episodic memory consolidation. Here, we instead aimed to modulate hippocampal activity during slow-wave sleep using transcranial direct current stimulation in 18 healthy humans. A pair-associate episodic memory task was used to evaluate sleep-dependent memory consolidation with face–occupation stimuli. Pre- and post-nap retrieval was assessed as a measure of memory performance. Anodal stimulation with 2 mA was applied bilaterally over the lateral temporal cortex, motivated by its particularly extensive connections to the hippocampus. The participants slept in a magnetic resonance (MR)-simulator during the recordings to test the feasibility for a future MR-study. We used a sham-controlled, double-blind, counterbalanced randomized, within-subject crossover design. We show that stimulation vs. sham significantly increased slow-wave density and the temporal coupling of fast spindles and slow-waves. While retention of episodic memories across sleep was not affected across the entire sample of participants, it was impaired in participants with below-average pre-sleep memory performance. Hence, bi-temporal anodal direct current stimulation applied during sleep enhanced sleep parameters that are typically involved in memory consolidation, but it failed to improve memory consolidation and even tended to impair consolidation in poor learners. These findings suggest that artificially enhancing memory-related sleep parameters to improve memory consolidation can actually backfire in those participants who are in most need of memory improvement.
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Affiliation(s)
- Simon Ruch
- Cognitive Neuroscience of Memory and Consciousness, Institute of Psychology, University of Bern, 3012 Bern, Switzerland;
- Department of Neurosurgery and Neurotechnology, Institute for Neuromodulation and Neurotechnology, University of Tübingen, 72076 Tübingen, Germany
| | - Kristoffer Fehér
- Translational Research Center, University Hospital of Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland; (K.F.); (S.H.); (Y.M.); (S.M.M.); (S.V.M.); (T.D.)
| | - Stephanie Homan
- Translational Research Center, University Hospital of Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland; (K.F.); (S.H.); (Y.M.); (S.M.M.); (S.V.M.); (T.D.)
- Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital of Psychiatry, University of Zurich, 8032 Zurich, Switzerland
| | - Yosuke Morishima
- Translational Research Center, University Hospital of Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland; (K.F.); (S.H.); (Y.M.); (S.M.M.); (S.V.M.); (T.D.)
| | - Sarah Maria Mueller
- Translational Research Center, University Hospital of Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland; (K.F.); (S.H.); (Y.M.); (S.M.M.); (S.V.M.); (T.D.)
| | - Stefanie Verena Mueller
- Translational Research Center, University Hospital of Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland; (K.F.); (S.H.); (Y.M.); (S.M.M.); (S.V.M.); (T.D.)
| | - Thomas Dierks
- Translational Research Center, University Hospital of Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland; (K.F.); (S.H.); (Y.M.); (S.M.M.); (S.V.M.); (T.D.)
| | - Matthias Grieder
- Translational Research Center, University Hospital of Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland; (K.F.); (S.H.); (Y.M.); (S.M.M.); (S.V.M.); (T.D.)
- Correspondence:
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11
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Semyachkina-Glushkovskaya O, Postnov D, Penzel T, Kurths J. Sleep as a Novel Biomarker and a Promising Therapeutic Target for Cerebral Small Vessel Disease: A Review Focusing on Alzheimer's Disease and the Blood-Brain Barrier. Int J Mol Sci 2020; 21:ijms21176293. [PMID: 32878058 PMCID: PMC7504101 DOI: 10.3390/ijms21176293] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/14/2020] [Accepted: 08/26/2020] [Indexed: 12/12/2022] Open
Abstract
Cerebral small vessel disease (CSVD) is a leading cause of cognitive decline in elderly people and development of Alzheimer’s disease (AD). Blood–brain barrier (BBB) leakage is a key pathophysiological mechanism of amyloidal CSVD. Sleep plays a crucial role in keeping health of the central nervous system and in resistance to CSVD. The deficit of sleep contributes to accumulation of metabolites and toxins such as beta-amyloid in the brain and can lead to BBB disruption. Currently, sleep is considered as an important informative platform for diagnosis and therapy of AD. However, there are no effective methods for extracting of diagnostic information from sleep characteristics. In this review, we show strong evidence that slow wave activity (SWA) (0–0.5 Hz) during deep sleep reflects glymphatic pathology, the BBB leakage and memory deficit in AD. We also discuss that diagnostic and therapeutic targeting of SWA in AD might lead to be a novel era in effective therapy of AD. Moreover, we demonstrate that SWA can be pioneering non-invasive and bed–side technology for express diagnosis of the BBB permeability. Finally, we review the novel data about the methods of detection and enhancement of SWA that can be biomarker and a promising therapy of amyloidal CSVD and CSVD associated with the BBB disorders.
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Affiliation(s)
- Oxana Semyachkina-Glushkovskaya
- Department of Human and Animal Physiology, Saratov State University, Astrakhanskaya Str. 83, 410012 Saratov, Russia; (D.P.); (T.P.); (J.K.)
- Physics Department, Humboldt University, Newtonstrasse 15, 12489 Berlin, Germany
- Correspondence: ; Tel.: +7-927-115-5157
| | - Dmitry Postnov
- Department of Human and Animal Physiology, Saratov State University, Astrakhanskaya Str. 83, 410012 Saratov, Russia; (D.P.); (T.P.); (J.K.)
| | - Thomas Penzel
- Department of Human and Animal Physiology, Saratov State University, Astrakhanskaya Str. 83, 410012 Saratov, Russia; (D.P.); (T.P.); (J.K.)
- Advanced Sleep Research GmbH, 12489 Berlin, Germany
- Charité-Universitätsmedizin Berlin, Sleep Medicine Center, Charitéplatz 1, 10117 Berlin, Germany
| | - Jürgen Kurths
- Department of Human and Animal Physiology, Saratov State University, Astrakhanskaya Str. 83, 410012 Saratov, Russia; (D.P.); (T.P.); (J.K.)
- Physics Department, Humboldt University, Newtonstrasse 15, 12489 Berlin, Germany
- Potsdam Institute for Climate Impact Research, Telegrafenberg A31, 14473 Potsdam, Germany
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12
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Scholes S, Santisteban JA, Zhang Y, Bertone A, Gruber R. Modulation of Slow-Wave Sleep: Implications for Psychiatry. Curr Psychiatry Rep 2020; 22:52. [PMID: 32710222 DOI: 10.1007/s11920-020-01175-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE OF REVIEW The objectives of this review are to examine and integrate existing empirical evidence regarding the impact of slow-wave sleep (SWS) modulation on memory and executive function performance in individuals with psychiatric disorders, and to examine the feasibility of integrating SWS modulation into psychiatric care. RECENT FINDINGS SWS modulation in individuals with psychiatric disorders resulted in changes to SWS across multiple psychiatric disorders, using all stimulation methods. SWS stimulation was associated with improved cognitive performance. SWS modulation using acoustic stimulation resulted in improved cognitive performance in children with ADHD, and the use of transcranial stimulation was associated with improved cognitive performance in individuals with mild cognitive impairment. Significant relationships between changes in SWS and cognitive improvement were found for individual with mild cognitive impairment following the use of acoustic or transcranial stimulation night. Our review reveals partial support to the potential efficacy of SWS modulation as a transdiagnostic intervention that uses sleep to improve cognitive functions of individuals diagnosed with psychiatric disorders and cognitive deficits. It further highlights multiple barriers pertaining to the feasibility of integrating SWS modulation into clinical practice and proposes ways to improve it.
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Affiliation(s)
- Samantha Scholes
- Attention, Behaviour and Sleep Lab, Douglas Mental Health University Institute, 6875 LaSalle Boulevard, Verdun, Montréal, QC, H4H 1R3, Canada.,Perceptual Neuroscience Lab (PNLab) for Autism, Development Department of Educational and Counselling Psychology, McGill University, Montréal, QC, Canada
| | - J A Santisteban
- Attention, Behaviour and Sleep Lab, Douglas Mental Health University Institute, 6875 LaSalle Boulevard, Verdun, Montréal, QC, H4H 1R3, Canada
| | - Yujie Zhang
- Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Armando Bertone
- Perceptual Neuroscience Lab (PNLab) for Autism, Development Department of Educational and Counselling Psychology, McGill University, Montréal, QC, Canada
| | - Reut Gruber
- Attention, Behaviour and Sleep Lab, Douglas Mental Health University Institute, 6875 LaSalle Boulevard, Verdun, Montréal, QC, H4H 1R3, Canada. .,Department of Psychiatry, Faculty of Medicine, McGill University, Montréal, QC, Canada.
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Heinrich B, Schmitt B, Bölsterli BK, Critelli H, Huber R, Fattinger S. Disparate effects of hormones and vigabatrin on sleep slow waves in patients with West syndrome - An indication of their mode of action? J Sleep Res 2020; 30:e13137. [PMID: 32657499 DOI: 10.1111/jsr.13137] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 05/17/2020] [Accepted: 06/08/2020] [Indexed: 01/22/2023]
Abstract
Synaptic downscaling during sleep, a physiological process to restore synaptic homeostasis and maintain learning efficiency and healthy brain development, has been related to a reduction of the slope of sleep slow waves (SSW). However, such synaptic downscaling seems not to be reflected in high-amplitude SSW. Recently we have shown reduced SSW slopes during hormonal treatment (adrenocorticotrophic hormone, prednisolone) in patients with West syndrome (WS). Yet, whether this reduction was related to successful treatment or reflects a specific effect of hormone therapy is unknown. Thus, we retrospectively analysed nap electroencephalograms of 61 patients with WS successfully treated with hormones, vigabatrin (VGB), or both. The slope of SSW during treatment (T1) and 2-7 months later (T2) when hormonal treatment was tapered off were compared between the treatment groups and healthy, age-matched controls. At T1 hormone treatment reduced the slope of low-amplitude SSW, whereas VGB increased the slope of high-amplitude SSW (linear mixed effect model: FGroup = 7.04, p < 0.001; FAmplitude = 1,646.68, p < 0.001; FGroup*Amplitude = 3.38, p < 0.001). At T2, untreated patients did not differ anymore from healthy controls, whereas those still under VGB showed the same alterations as those with VGB at T1. This result indicates a disparate effect of VGB and hormone on the SSW slope. In particular, hormones seem to reduce the slope of cortical generated low-amplitude SSW, similar to the physiological synaptic downscaling during sleep. Thus, a loss of functional neuronal connectivity might be an alternative explanation of the antiepileptic effect of hormonal treatment.
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Affiliation(s)
- Bianka Heinrich
- Department of Neuropediatrics, University Children's Hospital Zurich, Zürich, Switzerland
| | - Bernhard Schmitt
- Department of Neuropediatrics, University Children's Hospital Zurich, Zürich, Switzerland.,Pediatric Sleep Disorders Center, University Children's Hospital Zurich, Zürich, Switzerland.,Children's Research Center, University Children's Hospital Zurich, Zürich, Switzerland
| | - Bigna K Bölsterli
- Department of Neuropediatrics, University Children's Hospital Zurich, Zürich, Switzerland.,Pediatric Sleep Disorders Center, University Children's Hospital Zurich, Zürich, Switzerland.,Children's Research Center, University Children's Hospital Zurich, Zürich, Switzerland
| | - Hanne Critelli
- Department of Neuropediatrics, University Children's Hospital Zurich, Zürich, Switzerland.,Pediatric Sleep Disorders Center, University Children's Hospital Zurich, Zürich, Switzerland
| | - Reto Huber
- Pediatric Sleep Disorders Center, University Children's Hospital Zurich, Zürich, Switzerland.,Children's Research Center, University Children's Hospital Zurich, Zürich, Switzerland.,Child Development Center, University Children's Hospital Zurich, Zürich, Switzerland.,Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital, University of Zurich, Zürich, Switzerland
| | - Sara Fattinger
- Pediatric Sleep Disorders Center, University Children's Hospital Zurich, Zürich, Switzerland.,Children's Research Center, University Children's Hospital Zurich, Zürich, Switzerland.,Child Development Center, University Children's Hospital Zurich, Zürich, Switzerland
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15
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Garcia-Molina G, Tsoneva T, Neff A, Salazar J, Bresch E, Grossekathofer U, Pastoor S, Aquino A. Hybrid in-phase and continuous auditory stimulation significantly enhances slow wave activity during sleep. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2019:4052-4055. [PMID: 31946762 DOI: 10.1109/embc.2019.8857678] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Recent evidence has shown that enhancing slow-wave activity (SWA) during sleep has positive effects on cognitive, metabolic, and autonomic function. We have developed a consumer, integrated device that automatically detects sleep stages from a single electroencephalogram (EEG) signal and delivers auditory stimulation in a closed-loop manner. The stimulation was delivered in 15-auditory tone blocks separated from each other by at least 15 seconds. The first tone in a block was synchronized to the up-state of a detected slow-wave while subsequent ones were separated from each other by a constant 1-second inter-tone interval. The system was tested in a study involving 22 participants and SWA enhancement (average 45.8%; p=0.0027) was found in 19/22 participants.
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16
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Cook JD, Ferry DG, Tran KM. Sleep's role in preventing and treating Alzheimer's disease: are we moving towards slow-wave assessment and enhancement? Sleep 2020; 43:5677510. [PMID: 31837225 DOI: 10.1093/sleep/zsz304] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 12/06/2019] [Indexed: 12/16/2022] Open
Affiliation(s)
- Jesse D Cook
- Department of Psychiatry, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI.,Department of Psychology, University of Wisconsin-Madison, Madison, WI
| | - David G Ferry
- Department of Psychiatry, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI
| | - Kieulinh M Tran
- Department of Psychiatry, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI
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Feld GB, Born J. Neurochemical mechanisms for memory processing during sleep: basic findings in humans and neuropsychiatric implications. Neuropsychopharmacology 2020; 45:31-44. [PMID: 31443105 PMCID: PMC6879745 DOI: 10.1038/s41386-019-0490-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 07/17/2019] [Accepted: 07/22/2019] [Indexed: 12/14/2022]
Abstract
Sleep is essential for memory formation. Active systems consolidation maintains that memory traces that are initially stored in a transient store such as the hippocampus are gradually redistributed towards more permanent storage sites such as the cortex during sleep replay. The complementary synaptic homeostasis theory posits that weak memory traces are erased during sleep through a competitive down-selection mechanism, ensuring the brain's capability to learn new information. We discuss evidence from neuropharmacological experiments in humans to show how major neurotransmitters and neuromodulators are implicated in these memory processes. As to the major excitatory neurotransmitter glutamate that plays a prominent role in inducing synaptic consolidation, we show that these processes, while strengthening cortical memory traces during sleep, are insufficient to explain the consolidation of hippocampus-dependent declarative memories. In the inhibitory GABAergic system, we will offer insights how drugs may alter the intricate interplay of sleep oscillations that have been identified to be crucial for strengthening memories during sleep. Regarding the dopaminergic reward system, we will show how it is engaged during sleep replay, but that dopaminergic neuromodulation likely plays a side role for enhancing relevant memories during sleep. Also, we briefly go into basic evidence on acetylcholine and cortisol whose low tone during slow wave sleep (SWS) is crucial in supporting hippocampal-to-neocortical memory transmission. Finally, we will outline how these insights can be used to improve treatment of neuropsychiatric disorders focusing mainly on anxiety disorders, depression, and addiction that are strongly related to memory processing.
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Affiliation(s)
- Gordon B Feld
- Department of Clinical Psychology, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.
- Department of Addiction Behavior and Addiction Medicine, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.
| | - Jan Born
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
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Marshall L, Cross N, Binder S, Dang-Vu TT. Brain Rhythms During Sleep and Memory Consolidation: Neurobiological Insights. Physiology (Bethesda) 2020; 35:4-15. [DOI: 10.1152/physiol.00004.2019] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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.
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Affiliation(s)
- Lisa Marshall
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Luebeck, Luebeck, Germany
- Center for Brain, Behavior and Metabolism, University of Luebeck, Luebeck, Germany
| | - Nathan Cross
- Perform Center, Center for Studies in Behavioral Neurobiology, and Department of Health, Kinesiology and Applied Physiology, Concordia University, Montreal, Quebec, Canada
- Centre de Recherche de l’Institut Universitaire de Gériatrie de Montréal, CIUSSS Centre-Sud-de-l’Ile-de-Montréal, Montreal, Quebec, Canada
| | - Sonja Binder
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Luebeck, Luebeck, Germany
- Center for Brain, Behavior and Metabolism, University of Luebeck, Luebeck, Germany
| | - Thien Thanh Dang-Vu
- Perform Center, Center for Studies in Behavioral Neurobiology, and Department of Health, Kinesiology and Applied Physiology, Concordia University, Montreal, Quebec, Canada
- Centre de Recherche de l’Institut Universitaire de Gériatrie de Montréal, CIUSSS Centre-Sud-de-l’Ile-de-Montréal, Montreal, Quebec, Canada
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19
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Lee M, Song CB, Shin GH, Lee SW. Possible Effect of Binaural Beat Combined With Autonomous Sensory Meridian Response for Inducing Sleep. Front Hum Neurosci 2019; 13:425. [PMID: 31849629 PMCID: PMC6900908 DOI: 10.3389/fnhum.2019.00425] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 11/15/2019] [Indexed: 12/22/2022] Open
Abstract
Sleep is important to maintain physical and cognitive functions in everyday life. However, the prevalence of sleep disorders is on the rise. One existing solution to this problem is to induce sleep using an auditory stimulus. When we listen to acoustic beats of two tones in each ear simultaneously, a binaural beat is generated which induces brain signals at a specific desired frequency. However, this auditory stimulus is uncomfortable for users to listen to induce sleep. To overcome this difficulty, we can exploit the feelings of calmness and relaxation that are induced by the perceptual phenomenon of autonomous sensory meridian response (ASMR). In this study, we proposed a novel auditory stimulus for inducing sleep. Specifically, we used a 6 Hz binaural beat corresponding to the center of the theta band (4-8 Hz), which is the frequency at which brain activity is entrained during non-rapid eye movement (NREM) in sleep stage 1. In addition, the "ASMR triggers" that cause ASMR were presented from natural sound as the sensory stimuli. In session 1, we combined two auditory stimuli (the 6 Hz binaural beat and ASMR triggers) at three-decibel ratios to find the optimal combination ratio. As a result, we determined that the combination of a 30:60 dB ratio of binaural beat to ASMR trigger is most effective for inducing theta power and psychological stability. In session 2, the effects of these combined stimuli (CS) were compared with an only binaural beat, only the ASMR trigger, or a sham condition. The combination stimulus retained the advantages of the binaural beat and resolved its shortcomings with the ASMR triggers, including psychological self-reports. Our findings indicate that the proposed auditory stimulus could induce the brain signals required for sleep, while simultaneously keeping the user in a psychologically comfortable state. This technology provides an important opportunity to develop a novel method for increasing the quality of sleep.
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Affiliation(s)
- Minji Lee
- Department of Brain and Cognitive Engineering, Korea University, Seoul, South Korea
| | - Chae-Bin Song
- Department of Brain and Cognitive Engineering, Korea University, Seoul, South Korea
| | - Gi-Hwan Shin
- Department of Brain and Cognitive Engineering, Korea University, Seoul, South Korea
| | - Seong-Whan Lee
- Department of Brain and Cognitive Engineering, Korea University, Seoul, South Korea
- Department of Artificial Intelligence, Korea University, Seoul, South Korea
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20
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Partial restoration of physiological UP-state activity by GABA pathway modulation in an acute brain slice model of epilepsy. Neuropharmacology 2019; 148:394-405. [DOI: 10.1016/j.neuropharm.2018.11.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 10/13/2018] [Accepted: 11/21/2018] [Indexed: 01/31/2023]
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21
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Zhang Y, Gruber R. Can Slow-Wave Sleep Enhancement Improve Memory? A Review of Current Approaches and Cognitive Outcomes. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2019; 92:63-80. [PMID: 30923474 PMCID: PMC6430170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Slow-wave sleep (SWS) is involved in the overnight consolidation of declarative memories. Recent efforts using auditory stimulation, slow-oscillatory transcranial direct current stimulation (so-tDCS), and pharmacological agents have targeted sleep slow-waves as a method for enhancing cognitive performance. However, no studies thus far have integrated current evidence to provide a preliminary review of the effects of SWS enhancement on memory and other cognitive outcomes. The objective of this review was to synthesize the results of recent experimental studies that have used auditory stimulation, electrical, and pharmacological methods to boost both SWS and cognitive performance. A systematic review was done to identify and consolidate all currently existing empirical studies in this area. We found that each stimulation method could enhance slow-wave power and/or SWS duration in human subjects. Closed-loop, in-phase auditory stimulation enhanced verbal declarative memory in healthy adults. Electrical stimulation using so-tDCS showed some efficacy in promoting verbal declarative memory, picture recognition memory, and location memory. Interleukin-6 and sodium oxybate enhanced declarative verbal memory, while tiagabine and sodium oxybate improved some non-memory measures of cognitive performance. There is some evidence that so-tDCS can also improve certain cognitive outcomes in clinical populations. Overall, future studies should recruit larger sample sizes drawn from more diverse populations, and determine clinical significance and effect sizes of each enhancement methodology.
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Affiliation(s)
- Yujie Zhang
- Department of Psychology, McGill University, Montréal, QC, Canada
| | - Reut Gruber
- Department of Psychiatry, McGill University, Montréal, QC, Canada,To whom all correspondence should be addressed: Reut Gruber, PhD Psychologist; Department of Psychiatry, Faculty of Medicine, McGill University; Director of Attention Behavior and Sleep Lab, Douglas Mental Health University Institute; 6875 LaSalle Blvd, Montréal, QC, Canada H4H 1R3; Tel: 5147616131 ext. 3476;
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22
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Santiago JCP, Ngo HV, Jickeli C, Peter A, Hallschmid M. Intensifying sleep slow oscillations does not improve metabolic control in healthy men. Psychoneuroendocrinology 2019; 99:1-7. [PMID: 30172070 DOI: 10.1016/j.psyneuen.2018.08.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 08/03/2018] [Accepted: 08/21/2018] [Indexed: 12/14/2022]
Abstract
Impaired sleep quality and sleep loss compromise glucose homeostasis and metabolic function, but the mechanisms linking sleep and metabolic health are largely unclear. In order to gain insight into the relevance of specific electrophysiological sleep characteristics for metabolic control, we assessed the acute effect on glucose homeostasis as well as energy intake and expenditure of enhancing slow oscillatory activity, a hallmark of slow-wave sleep, by closed-loop auditory stimulation in healthy men. Twenty-two young, normal-weight men underwent an oral glucose tolerance test (oGTT), indirect calorimetry and the assessment of ad-libitum breakfast intake in the morning after nocturnal sleep with or without auditory stimulation in phase with the ongoing rhythmic occurrence of slow oscillation up-states during 210 min of slow-wave sleep in the first night-half. Stimulation vs. no stimulation strongly increased slow oscillatory activity without changing overall sleep structure, but did not alter fasting or oGTT-stimulated measures of glucose homeostasis. Food intake and energy expenditure were likewise comparable between conditions. Findings indicate that in healthy humans electrophysiological sleep quality is tuned to allow for optimal metabolic control. Future studies should investigate the potential of sleep stage-specific interventions to enhance metabolic control and well-being in patients with metabolic ailments.
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Affiliation(s)
- João C P Santiago
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, 72076 Tübingen, Germany; German Center for Diabetes Research (DZD), 72076 Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, 72076 Tübingen, Germany
| | - Hong-Viet Ngo
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, 72076 Tübingen, Germany; School of Psychology, University of Birmingham, B15 2TT Birmingham, UK
| | - Carola Jickeli
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, 72076 Tübingen, Germany
| | - Andreas Peter
- German Center for Diabetes Research (DZD), 72076 Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, 72076 Tübingen, Germany; Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, University Hospital of Tübingen, 72076 Tübingen, Germany
| | - Manfred Hallschmid
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, 72076 Tübingen, Germany; German Center for Diabetes Research (DZD), 72076 Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, 72076 Tübingen, Germany.
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23
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Cellini N, Mednick SC. Stimulating the sleeping brain: Current approaches to modulating memory-related sleep physiology. J Neurosci Methods 2018; 316:125-136. [PMID: 30452977 DOI: 10.1016/j.jneumeth.2018.11.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 10/25/2018] [Accepted: 11/14/2018] [Indexed: 10/27/2022]
Abstract
BACKGROUND One of the most audacious proposals throughout the history of psychology was the potential ability to learn while we sleep. The idea penetrated culture via sci-fi movies and inspired the invention of devices that claimed to teach foreign languages, facts, and even quit smoking by simply listening to audiocassettes or other devices during sleep. However, the promises from this endeavor didn't stand up to experimental scrutiny, and the dream was shunned from the scientific community. Despite the historic evidence that the sleeping brain cannot learn new complex information (i.e., words, images, facts), a new wave of current interventions are demonstrating that sleep can be manipulated to strengthen recent memories. NEW METHOD Several recent approaches have been developed that play with the sleeping brain in order to modify ongoing memory processing. Here, we provide an overview of the available techniques to non-invasively modulate memory-related sleep physiology, including sensory, vestibular and electrical stimulation, as well as pharmacological approaches. RESULTS N/A. COMPARISON WITH EXISTING METHODS N/A. CONCLUSIONS Although the results are encouraging, suggesting that in general the sleeping brain may be optimized for better memory performance, the road to bring these techniques in free-living conditions is paved with unanswered questions and technical challenges that need to be carefully addressed.
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Affiliation(s)
- Nicola Cellini
- Department of General Psychology, University of Padova, Padova, Italy.
| | - Sara C Mednick
- Department of Cognitive Sciences, University of California, Irvine, United States
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24
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Léger D, Debellemaniere E, Rabat A, Bayon V, Benchenane K, Chennaoui M. Slow-wave sleep: From the cell to the clinic. Sleep Med Rev 2018; 41:113-132. [DOI: 10.1016/j.smrv.2018.01.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 01/02/2018] [Accepted: 01/22/2018] [Indexed: 10/18/2022]
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25
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Garcia-Molina G, Tsoneva T, Jasko J, Steele B, Aquino A, Baher K, Pastoor S, Pfundtner S, Ostrowski L, Miller B, Papas N, Riedner B, Tononi G, White DP. Closed-loop system to enhance slow-wave activity. J Neural Eng 2018; 15:066018. [PMID: 30215604 DOI: 10.1088/1741-2552/aae18f] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE Recent evidence reports cognitive, metabolic, and sleep restoration benefits resulting from the enhancement of sleep slow-waves using auditory stimulation. Our objective is to make this concept practical for consumer use by developing and validating an electroencephalogram (EEG) closed-loop system to deliver auditory stimulation during sleep to enhance slow-waves. APPROACH The system automatically detects slow-wave sleep with 74% sensitivity and 97% specificity and optimally delivers stimulation in the form of 50 ms-long tones separated by a constant one-second inter-tone interval at a volume that is dynamically modulated such that louder tones are delivered when sleep is deeper. The system was tested in a study involving 28 participants (18F, 10M; 36.9 ± 7.3 years old; median age: 40 years old) who used the system for ten nights (five nights in a sham condition and five in a stimulation condition). Four nights in each condition were recorded at-home and the fifth one in-lab. MAIN RESULTS The analysis in two age groups defined by the median age of participants in the study shows significant slow wave activity enhancement (+16.1%, p < 0.01) for the younger group and absence of effect on the older group. However, the older group received only a fraction (57%) of the stimulation compared to the younger group. Changes in sleep architecture and EEG properties due to aging have influenced the amount of stimulation. The analysis of the stimulation timing suggests an entrainment-like phenomenon where slow-waves align to the stimulation periodicity. In addition, enhancement of spindle power in the stimulation condition was found. SIGNIFICANCE We show evidence of the viability of delivering auditory stimulation during sleep, at home, to enhance slow wave activity. The system ensures the stimulation delivery to be at the right time during sleep without causing disturbance.
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Affiliation(s)
- Gary Garcia-Molina
- Sleep and Respiratory Care, Philips, Pittsburgh, PA, United States of America. Department of Psychiatry, University of Wisconsin-Madison, Madison, WI, United States of America
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Wilckens KA, Ferrarelli F, Walker MP, Buysse DJ. Slow-Wave Activity Enhancement to Improve Cognition. Trends Neurosci 2018; 41:470-482. [PMID: 29628198 PMCID: PMC6015540 DOI: 10.1016/j.tins.2018.03.003] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 02/26/2018] [Accepted: 03/05/2018] [Indexed: 02/07/2023]
Abstract
Slow-wave activity (SWA), and its coupling with other sleep features, reorganizes cortical circuitry, supporting cognition. This raises the question: can cognition be improved through SWA enhancement? SWA enhancement techniques range from behavioral interventions (such as exercise), which have high feasibility but low specificity, to laboratory-based techniques (such as transcranial stimulation), which have high specificity but are less feasible for widespread use. In this review we describe the pathways through which SWA is enhanced. Pathways encompass enhanced neural activity, increased energy metabolism, and endocrine signaling during wakefulness; also direct enhancement during sleep. We evaluate the robustness and practicality of SWA-enhancement techniques, discuss approaches for determining a causal role of SWA on cognition, and present questions to clarify the mechanisms of SWA-dependent cognitive improvements.
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Affiliation(s)
- Kristine A Wilckens
- University of Pittsburgh School of Medicine, Department of Psychiatry, Pittsburgh, PA, USA.
| | - Fabio Ferrarelli
- University of Pittsburgh School of Medicine, Department of Psychiatry, Pittsburgh, PA, USA
| | - Matthew P Walker
- University of California, Berkeley, Department of Psychology, CA, USA
| | - Daniel J Buysse
- University of Pittsburgh School of Medicine, Department of Psychiatry, Pittsburgh, PA, USA
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Ong JL, Patanaik A, Chee NIYN, Lee XK, Poh JH, Chee MWL. Auditory stimulation of sleep slow oscillations modulates subsequent memory encoding through altered hippocampal function. Sleep 2018; 41:4841646. [PMID: 29425369 PMCID: PMC5946855 DOI: 10.1093/sleep/zsy031] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 12/23/2017] [Indexed: 01/23/2023] Open
Abstract
Study Objectives Slow oscillations (SO) during sleep contribute to the consolidation of learned material. How the encoding of declarative memories during subsequent wakefulness might benefit from their enhancement during sleep is less clear. In this study, we investigated the impact of acoustically enhanced SO during a nap on subsequent encoding of declarative material. Methods Thirty-seven healthy young adults were studied under two conditions: stimulation (STIM) and no stimulation (SHAM), in counter-balanced order following a night of sleep restriction (4 hr time-in-bed [TIB]). In the STIM condition, auditory tones were phase-locked to the SO up-state during a 90 min nap opportunity. In the SHAM condition, corresponding time points were marked but tones were not presented. Thirty minutes after awakening, participants encoded pictures while undergoing fMRI. Picture recognition was tested 60 min later. Results Acoustic stimulation augmented SO across the group, but there was no group level benefit on memory. However, the magnitude of SO enhancement correlated with greater recollection. SO enhancement was also positively correlated with hippocampal activation at encoding. Although spindle activity increased, this did not correlate with memory benefit or shift in hippocampal signal. Conclusions Acoustic stimulation during a nap can benefit encoding of declarative memories. Hippocampal activation positively correlated with SO augmentation.
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Affiliation(s)
- Ju Lynn Ong
- Centre for Cognitive Neuroscience, Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
| | - Amiya Patanaik
- Centre for Cognitive Neuroscience, Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
| | - Nicholas I Y N Chee
- Centre for Cognitive Neuroscience, Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
| | - Xuan Kai Lee
- Centre for Cognitive Neuroscience, Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
| | - Jia-Hou Poh
- Centre for Cognitive Neuroscience, Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
| | - Michael W L Chee
- Centre for Cognitive Neuroscience, Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
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Linares IMP, Guimaraes FS, Eckeli A, Crippa ACS, Zuardi AW, Souza JDS, Hallak JE, Crippa JAS. No Acute Effects of Cannabidiol on the Sleep-Wake Cycle of Healthy Subjects: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study. Front Pharmacol 2018; 9:315. [PMID: 29674967 PMCID: PMC5895650 DOI: 10.3389/fphar.2018.00315] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 03/19/2018] [Indexed: 12/17/2022] Open
Abstract
Cannabidiol (CBD) is a component of Cannabis sativa that has a broad spectrum of potential therapeutic effects in neuropsychiatric and other disorders. However, few studies have investigated the possible interference of CBD on the sleep-wake cycle. The aim of the present study was to evaluate the effect of a clinically anxiolytic dose of CBD on the sleep-wake cycle of healthy subjects in a crossover, double-blind design. Twenty-seven healthy volunteers that fulfilled the eligibility criteria were selected and allocated to receive either CBD (300 mg) or placebo in the first night in a double-blind randomized design (one volunteer withdrew from the study). In the second night, the same procedure was performed using the substance that had not been administered in the previous occasion. CBD or placebo were administered 30 min before the start of polysomnography recordings that lasted 8 h. Cognitive and subjective measures were performed immediately after polysomnography to assess possible residual effects of CBD. The drug did not induce any significant effect (p > 0.05). Different from anxiolytic and antidepressant drugs such as benzodiazepines and selective serotonin reuptake inhibitors, acute administration of an anxiolytic dose of CBD does not seem to interfere with the sleep cycle of healthy volunteers. The present findings support the proposal that CBD do not alter normal sleep architecture. Future studies should address the effects of CBD on the sleep-wake cycle of patient populations as well as in clinical trials with larger samples and chronic use of different doses of CBD. Such studies are desirable and opportune.
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Affiliation(s)
- Ila M. P. Linares
- Department of Neurosciences and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil
- Instituto Nacional de Ciência e Tecnologia Translacional em Medicina, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brasília, Brazil
| | - Francisco S. Guimaraes
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil
| | - Alan Eckeli
- Department of Neurosciences and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil
- Instituto Nacional de Ciência e Tecnologia Translacional em Medicina, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brasília, Brazil
| | - Ana C. S. Crippa
- Department of Pediatrics, Neuropediatrics, Federal University of Paraná, Curitiba, Brazil
| | - Antonio W. Zuardi
- Department of Neurosciences and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil
- Instituto Nacional de Ciência e Tecnologia Translacional em Medicina, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brasília, Brazil
| | - Jose D. S. Souza
- Department of Neurosciences and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil
- Instituto Nacional de Ciência e Tecnologia Translacional em Medicina, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brasília, Brazil
| | - Jaime E. Hallak
- Department of Neurosciences and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil
- Instituto Nacional de Ciência e Tecnologia Translacional em Medicina, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brasília, Brazil
| | - José A. S. Crippa
- Department of Neurosciences and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil
- Instituto Nacional de Ciência e Tecnologia Translacional em Medicina, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brasília, Brazil
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Ahuja S, Chen RK, Kam K, Pettibone WD, Osorio RS, Varga AW. Role of normal sleep and sleep apnea in human memory processing. Nat Sci Sleep 2018; 10:255-269. [PMID: 30214331 PMCID: PMC6128282 DOI: 10.2147/nss.s125299] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
A fundamental problem in the field of obstructive sleep apnea (OSA) and memory is that it has historically minimized the basic neurobiology of sleep's role in memory. Memory formation has been classically divided into phases of encoding, processing/consolidation, and retrieval. An abundance of evidence suggests that sleep plays a critical role specifically in the processing/consolidation phase, but may do so differentially for memories that were encoded using particular brain circuits. In this review, we discuss some of the more established evidence for sleep's function in the processing of declarative, spatial navigational, emotional, and motor/procedural memories and more emerging evidence highlighting sleep's importance in higher order functions such as probabilistic learning, transitive inference, and category/gist learning. Furthermore, we discuss sleep's capacity for memory augmentation through targeted/cued memory reactivation. OSA - by virtue of its associated sleep fragmentation, intermittent hypoxia, and potential brain structural effects - is well positioned to specifically impact the processing/consolidation phase, but testing this possibility requires experimental paradigms in which memory encoding and retrieval are separated by a period of sleep with and without the presence of OSA. We argue that such paradigms should focus on the specific types of memory tasks for which sleep has been shown to have a significant effect. We discuss the small number of studies in which this has been done, in which OSA nearly uniformly negatively impacts offline memory processing. When periods of offline processing are minimal or absent and do not contain sleep, as is the case in the broad literature on OSA and memory, the effects of OSA on memory are far less consistent.
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Affiliation(s)
- Shilpi Ahuja
- Mount Sinai Integrative Sleep Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA,
| | - Rebecca K Chen
- Mount Sinai Integrative Sleep Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA,
| | - Korey Kam
- Mount Sinai Integrative Sleep Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA,
| | - Ward D Pettibone
- Mount Sinai Integrative Sleep Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA,
| | - Ricardo S Osorio
- Center for Brain Health, Department of Psychiatry, NYU School of Medicine, New York, NY, USA
| | - Andrew W Varga
- Mount Sinai Integrative Sleep Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA,
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Promoting Sleep Oscillations and Their Functional Coupling by Transcranial Stimulation Enhances Memory Consolidation in Mild Cognitive Impairment. J Neurosci 2017. [PMID: 28637840 DOI: 10.1523/jneurosci.0260-17.2017] [Citation(s) in RCA: 146] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Alzheimer's disease (AD) not only involves loss of memory functions, but also prominent deterioration of sleep physiology, which is already evident at the stage of mild cognitive impairment (MCI). Cortical slow oscillations (SO; 0.5-1 Hz) and thalamocortical spindle activity (12-15 Hz) during sleep, and their temporal coordination, are considered critical for memory formation. We investigated the potential of slow oscillatory transcranial direct current stimulation (so-tDCS), applied during a daytime nap in a sleep-state-dependent manner, to modulate these activity patterns and sleep-related memory consolidation in nine male and seven female human patients with MCI. Stimulation significantly increased overall SO and spindle power, amplified spindle power during SO up-phases, and led to stronger synchronization between SO and spindle power fluctuations in EEG recordings. Moreover, visual declarative memory was improved by so-tDCS compared with sham stimulation and was associated with stronger synchronization. These findings indicate a well-tolerated therapeutic approach for disordered sleep physiology and memory deficits in MCI patients and advance our understanding of offline memory consolidation.SIGNIFICANCE STATEMENT In the light of increasing evidence that sleep disruption is crucially involved in the progression of Alzheimer's disease (AD), sleep appears as a promising treatment target in this pathology, particularly to counteract memory decline. This study demonstrates the potential of a noninvasive brain stimulation method during sleep in patients with mild cognitive impairment (MCI), a precursor of AD, and advances our understanding of its mechanism. We provide first time evidence that slow oscillatory transcranial stimulation amplifies the functional cross-frequency coupling between memory-relevant brain oscillations and improves visual memory consolidation in patients with MCI.
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31
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Mander BA, Winer JR, Walker MP. Sleep and Human Aging. Neuron 2017; 94:19-36. [PMID: 28384471 PMCID: PMC5810920 DOI: 10.1016/j.neuron.2017.02.004] [Citation(s) in RCA: 598] [Impact Index Per Article: 85.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 02/02/2017] [Accepted: 02/03/2017] [Indexed: 12/13/2022]
Abstract
Older adults do not sleep as well as younger adults. Why? What alterations in sleep quantity and quality occur as we age, and are there functional consequences? What are the underlying neural mechanisms that explain age-related sleep disruption? This review tackles these questions. First, we describe canonical changes in human sleep quantity and quality in cognitively normal older adults. Second, we explore the underlying neurobiological mechanisms that may account for these human sleep alterations. Third, we consider the functional consequences of age-related sleep disruption, focusing on memory impairment as an exemplar. We conclude with a discussion of a still-debated question: do older adults simply need less sleep, or rather, are they unable to generate the sleep that they still need?
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Affiliation(s)
- Bryce A Mander
- Sleep and Neuroimaging Laboratory, Department of Psychology, University of California, Berkeley, Berkeley, CA 94720-1650, USA
| | - Joseph R Winer
- Sleep and Neuroimaging Laboratory, Department of Psychology, University of California, Berkeley, Berkeley, CA 94720-1650, USA
| | - Matthew P Walker
- Sleep and Neuroimaging Laboratory, Department of Psychology, University of California, Berkeley, Berkeley, CA 94720-1650, USA; Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA 94720-1650, USA.
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32
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Schreiner T, Rasch B. The beneficial role of memory reactivation for language learning during sleep: A review. BRAIN AND LANGUAGE 2017; 167:94-105. [PMID: 27036946 DOI: 10.1016/j.bandl.2016.02.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 01/19/2016] [Accepted: 02/18/2016] [Indexed: 06/05/2023]
Abstract
Sleep is essential for diverse aspects of language learning. According to a prominent concept these beneficial effects of sleep rely on spontaneous reactivation processes. A series of recent studies demonstrated that inducing such reactivation processes by re-exposure to memory cues during sleep enhances foreign vocabulary learning. Building upon these findings, the present article reviews recent models and empirical findings concerning the beneficial effects of sleep on language learning. Consequently, the memory function of sleep, its neural underpinnings and the role of the sleeping brain in language learning will be summarized. Finally, we will propose a working model concerning the oscillatory requirements for successful reactivation processes and future research questions to advance our understanding of the role of sleep on language learning and memory processes in general.
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Affiliation(s)
- Thomas Schreiner
- University of Fribourg, Department of Psychology, Fribourg, Switzerland; Zurich Center for Interdisciplinary Sleep Research (ZiS), Zurich, Switzerland.
| | - Björn Rasch
- University of Fribourg, Department of Psychology, Fribourg, Switzerland; Zurich Center for Interdisciplinary Sleep Research (ZiS), Zurich, Switzerland.
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33
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Sculpting memory during sleep: concurrent consolidation and forgetting. Curr Opin Neurobiol 2017; 44:20-27. [PMID: 28278432 DOI: 10.1016/j.conb.2017.02.012] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 01/09/2017] [Accepted: 02/22/2017] [Indexed: 11/22/2022]
Abstract
There is compelling evidence that sleep actively supports the formation of long-lasting memory representations. Experimental cuing of memories proved that neural replay of representations during sleep plays a causal role for this consolidation, which has also been shown to promote neocortical synaptic plasticity and spine formation. Concurrently, sleep has been proposed to facilitate forgetting through processes of synaptic renormalisation. This view received indirect support by findings in humans of sleep enhancing TMS-evoked plasticity and capabilities for encoding new information. First direct behavioural evidence of sleep inducing forgetting has only recently emerged after encoding large amounts of stimuli in adults. We propose forgetting complements sleep-dependent consolidation and facilitates gist abstraction especially at high memory loads, when reactivation-based consolidation reaches capacity limits.
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Taranto-Montemurro L, Sands SA, Edwards BA, Azarbarzin A, Marques M, de Melo C, Eckert DJ, White DP, Wellman A. Effects of Tiagabine on Slow Wave Sleep and Arousal Threshold in Patients With Obstructive Sleep Apnea. Sleep 2017; 40:2667756. [PMID: 28364504 PMCID: PMC6084757 DOI: 10.1093/sleep/zsw047] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/02/2016] [Indexed: 12/30/2022] Open
Abstract
Introduction Obstructive sleep apnea (OSA) severity is markedly reduced during slow-wave sleep (SWS) even in patients with a severe disease. The reason for this improvement is uncertain but likely relates to non-anatomical factors (i.e. reduced arousability, chemosensitivity, and increased dilator muscle activity). The anticonvulsant tiagabine produces a dose-dependent increase in SWS in subjects without OSA. This study aimed to test the hypothesis that tiagabine would reduce OSA severity by raising the overall arousal threshold during sleep. Aims and Methods After a baseline physiology night to assess patients' OSA phenotypic traits, a placebo-controlled, double-blind, crossover trial of tiagabine 12 mg administered before sleep was performed in 14 OSA patients. Under each condition, we assessed the effects on sleep and OSA severity using standard clinical polysomnography. Results Tiagabine increased slow-wave activity (SWA) of the electroencephalogram (1-4 Hz) compared to placebo (1.8 [0.4] vs. 2.0 [0.5] LogμV2, p = .04) but did not reduce OSA severity (apnea-hypopnea index [AHI] 41.5 [20.3] vs. 39.1 [16.5], p > .5). SWS duration (25 [20] vs. 26 [43] mins, p > .5) and arousal threshold (-26.5 [5.0] vs. -27.6 [5.1] cmH2O, p = .26) were also unchanged between nights. Conclusions Tiagabine modified sleep microstructure (increase in SWA) but did not change the duration of SWS, OSA severity, or arousal threshold in this group of OSA patients. Based on these findings, tiagabine should not be considered as a therapeutic option for OSA treatment.
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Affiliation(s)
- Luigi Taranto-Montemurro
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham & Women's Hospital & Harvard Medical School, Boston, MA
| | - Scott A Sands
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham & Women's Hospital & Harvard Medical School, Boston, MA
- Department of Allergy, Immunology and Respiratory Medicine and Central Clinical School, The Alfred and Monash University, Melbourne, VIC Australia
| | - Bradley A Edwards
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham & Women's Hospital & Harvard Medical School, Boston, MA
- Sleep and Circadian Medicine Laboratory, Department of Physiology Monash University, Melbourne, VIC, Australia
- School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Melbourne, VIC, Australia
| | - Ali Azarbarzin
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham & Women's Hospital & Harvard Medical School, Boston, MA
| | - Melania Marques
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham & Women's Hospital & Harvard Medical School, Boston, MA
| | - Camila de Melo
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham & Women's Hospital & Harvard Medical School, Boston, MA
| | - Danny J Eckert
- Neuroscience Research Australia (NeuRA) and the University of New South Wales, Randwick, Sydney, Australia
| | - David P White
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham & Women's Hospital & Harvard Medical School, Boston, MA
| | - Andrew Wellman
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham & Women's Hospital & Harvard Medical School, Boston, MA
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Tactile stimulation during sleep alters slow oscillation and spindle densities but not motor skill. Physiol Behav 2016; 169:59-68. [PMID: 27887994 DOI: 10.1016/j.physbeh.2016.11.024] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 11/15/2016] [Accepted: 11/18/2016] [Indexed: 01/02/2023]
Abstract
Studies using targeted memory reactivation have shown that presentation of auditory or olfactory contextual cues during sleep can bias hippocampal reactivations towards the preferential replay of the cue-associated material, thereby resulting in enhanced consolidation of that information. If the same cortical ensembles are indeed used for encoding and storage of a given piece of information, forcing the sleeping brain to re-engage in task-intrinsic information processing should disturb the natural ongoing consolidation processes and therefore impair possible sleep benefits. Here we aimed at recreating an integral part of the sensory experience of a motor skill in a daytime nap, by means of a tactile stimulation. We hypothesized that tampering with the tactile component of a motor skill during sleep would result in hindered performance at retest, due to interference between the highly congruent incoming stimuli and the core skill trace. Contrary to our predictions, the tactile stimulation did not influence neither speed nor accuracy, when compared to natural sleep. However, an exploratory sleep EEG analysis revealed stimulation-induced alterations in the abundance and cortical topography of slow oscillations and spindles. These findings suggest that despite the lack of a significant effect on motor behavior, tactile stimulation induced changes in EEG features suggestive of a possible uncoupling between the sleep oscillations thought to underlie consolidation processes, i.e. slow oscillations and sleep spindles.
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36
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Weigenand A, Mölle M, Werner F, Martinetz T, Marshall L. Timing matters: open-loop stimulation does not improve overnight consolidation of word pairs in humans. Eur J Neurosci 2016; 44:2357-68. [PMID: 27422437 PMCID: PMC5113809 DOI: 10.1111/ejn.13334] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 06/13/2016] [Accepted: 07/06/2016] [Indexed: 11/29/2022]
Abstract
The application of auditory clicks during non‐rapid eye movement (NREM) sleep phase‐locked to the up state of the slow oscillation (closed‐loop stimulation) has previously been shown to enhance the consolidation of declarative memories. We designed and applied sequences of three clicks during deep NREM sleep to achieve a quasi‐phase‐dependent open‐loop stimulation. This stimulation was successful in eliciting slow oscillation power in the stimulation period. Although fast and slow spindle power were markedly decreased during the stimulation period, memory consolidation did not differ from control. During putative up states fast spindle power remained, however, at control levels. We conclude that concurrence of slow oscillations and fast spindles suffices to maintain memory consolidation at control levels despite an overall decreased spindle activity.
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Affiliation(s)
- Arne Weigenand
- Institute for Neuro- and Bioinformatics, University of Lübeck, Ratzeburger Allee 160, 23562, Lübeck, Germany. .,Graduate School for Computing in Medicine and Life Science, University of Lübeck, Lübeck, Germany.
| | - Matthias Mölle
- Center for Brain, Behavior and Metabolism, University of Lübeck, Lübeck, Germany.,Institute for Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | - Friederike Werner
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Ratzeburger Allee 160, 23562, Lübeck, Germany
| | - Thomas Martinetz
- Institute for Neuro- and Bioinformatics, University of Lübeck, Ratzeburger Allee 160, 23562, Lübeck, Germany.,Graduate School for Computing in Medicine and Life Science, University of Lübeck, Lübeck, Germany
| | - Lisa Marshall
- Graduate School for Computing in Medicine and Life Science, University of Lübeck, Lübeck, Germany. .,Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Ratzeburger Allee 160, 23562, Lübeck, Germany.
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37
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Mander BA, Winer JR, Jagust WJ, Walker MP. Sleep: A Novel Mechanistic Pathway, Biomarker, and Treatment Target in the Pathology of Alzheimer's Disease? Trends Neurosci 2016; 39:552-566. [PMID: 27325209 PMCID: PMC4967375 DOI: 10.1016/j.tins.2016.05.002] [Citation(s) in RCA: 288] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 04/13/2016] [Accepted: 05/10/2016] [Indexed: 12/16/2022]
Abstract
Sleep disruption appears to be a core component of Alzheimer's disease (AD) and its pathophysiology. Signature abnormalities of sleep emerge before clinical onset of AD. Moreover, insufficient sleep facilitates accumulation of amyloid-β (Aβ), potentially triggering earlier cognitive decline and conversion to AD. Building on such findings, this review has four goals: evaluating (i) associations and plausible mechanisms linking non-rapid-eye-movement (NREM) sleep disruption, Aβ, and AD; (ii) a role for NREM sleep disruption as a novel factor linking cortical Aβ to impaired hippocampus-dependent memory consolidation; (iii) the potential diagnostic utility of NREM sleep disruption as a new biomarker of AD; and (iv) the possibility of sleep as a new treatment target in aging, affording preventative and therapeutic benefits.
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Affiliation(s)
- Bryce A Mander
- Sleep and Neuroimaging Laboratory University of California, Berkeley, CA 94720-1650, USA.
| | - Joseph R Winer
- Sleep and Neuroimaging Laboratory University of California, Berkeley, CA 94720-1650, USA
| | - William J Jagust
- Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720-1650, USA; Molecular Biophysics and Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Matthew P Walker
- Sleep and Neuroimaging Laboratory University of California, Berkeley, CA 94720-1650, USA; Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720-1650, USA.
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38
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Lustenberger C, Boyle MR, Alagapan S, Mellin JM, Vaughn BV, Fröhlich F. Feedback-Controlled Transcranial Alternating Current Stimulation Reveals a Functional Role of Sleep Spindles in Motor Memory Consolidation. Curr Biol 2016; 26:2127-36. [PMID: 27476602 DOI: 10.1016/j.cub.2016.06.044] [Citation(s) in RCA: 165] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 05/19/2016] [Accepted: 06/20/2016] [Indexed: 12/12/2022]
Abstract
Transient episodes of brain oscillations are a common feature of both the waking and the sleeping brain. Sleep spindles represent a prominent example of a poorly understood transient brain oscillation that is impaired in disorders such as Alzheimer's disease and schizophrenia. However, the causal role of these bouts of thalamo-cortical oscillations remains unknown. Demonstrating a functional role of sleep spindles in cognitive processes has, so far, been hindered by the lack of a tool to target transient brain oscillations in real time. Here, we show, for the first time, selective enhancement of sleep spindles with non-invasive brain stimulation in humans. We developed a system that detects sleep spindles in real time and applies oscillatory stimulation. Our stimulation selectively enhanced spindle activity as determined by increased sigma activity after transcranial alternating current stimulation (tACS) application. This targeted modulation caused significant enhancement of motor memory consolidation that correlated with the stimulation-induced change in fast spindle activity. Strikingly, we found a similar correlation between motor memory and spindle characteristics during the sham night for the same spindle frequencies and electrode locations. Therefore, our results directly demonstrate a functional relationship between oscillatory spindle activity and cognition.
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Affiliation(s)
- Caroline Lustenberger
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Michael R Boyle
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA
| | - Sankaraleengam Alagapan
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Juliann M Mellin
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Bradley V Vaughn
- Department of Neurology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA
| | - Flavio Fröhlich
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA; Department of Neurology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA; Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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Central Nervous Insulin Signaling in Sleep-Associated Memory Formation and Neuroendocrine Regulation. Neuropsychopharmacology 2016; 41:1540-50. [PMID: 26448203 PMCID: PMC4832015 DOI: 10.1038/npp.2015.312] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 09/16/2015] [Accepted: 10/03/2015] [Indexed: 01/30/2023]
Abstract
The neurochemical underpinnings of sleep's contribution to the establishment and maintenance of memory traces are largely unexplored. Considering that intranasal insulin administration to the CNS improves memory functions in healthy and memory-impaired humans, we tested whether brain insulin signaling and sleep interact to enhance memory consolidation in healthy participants. We investigated the effect of intranasal insulin on sleep-associated neurophysiological and neuroendocrine parameters and memory consolidation in 16 men and 16 women (aged 18-30 years), who learned a declarative word-pair task and a procedural finger sequence tapping task in the evening before intranasal insulin (160 IU) or placebo administration and 8 h of nocturnal sleep. On the subsequent evening, they learned interfering word-pairs and a new finger sequence before retrieving the original memories. Insulin increased growth hormone concentrations in the first night-half and EEG delta power during the second 90 min of non-rapid-eye-movement sleep. Insulin treatment impaired the acquisition of new contents in both the declarative and procedural memory systems on the next day, whereas retrieval of original memories was unchanged. Results indicate that sleep-associated memory consolidation is not a primary mediator of insulin's acute memory-improving effect, but that the peptide acts on mechanisms that diminish the subsequent encoding of novel information. Thus, by inhibiting processes of active forgetting during sleep, central nervous insulin might reduce the interfering influence of encoding new information.
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40
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Sleep Spindles as Facilitators of Memory Formation and Learning. Neural Plast 2016; 2016:1796715. [PMID: 27119026 PMCID: PMC4826925 DOI: 10.1155/2016/1796715] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 03/13/2016] [Indexed: 01/08/2023] Open
Abstract
Over the past decades important progress has been made in understanding the mechanisms of sleep spindle generation. At the same time a physiological role of sleep spindles is starting to be revealed. Behavioural studies in humans and animals have found significant correlations between the recall performance in different learning tasks and the amount of sleep spindles in the intervening sleep. Concomitant neurophysiological experiments showed a close relationship between sleep spindles and other sleep related EEG rhythms as well as a relationship between sleep spindles and synaptic plasticity. Together, there is growing evidence from several disciplines in neuroscience for a participation of sleep spindles in memory formation and learning.
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41
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Goerke M, Müller NG, Cohrs S. Sleep-dependent memory consolidation and its implications for psychiatry. J Neural Transm (Vienna) 2015; 124:163-178. [PMID: 26518213 DOI: 10.1007/s00702-015-1476-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 10/20/2015] [Indexed: 02/06/2023]
Abstract
Both sleep disturbance and memory impairment are very common in psychiatric disorders. Since sleep has been shown to play a role in the process of transferring newly acquired information into long-term memory, i.e., consolidation, it is important to highlight this link in the context of psychiatric disorders. Along these lines, after providing a brief overview of healthy human sleep, current neurobiological models on sleep-dependent memory consolidation and resultant opportunities to manipulate the memory consolidation process, recent findings on sleep disturbances and sleep-dependent memory consolidation in patients with insomnia, major depression, schizophrenia, and post-traumatic stress disorder are systematically reviewed. Furthermore, possible underlying neuropathologies and their implications on therapeutic strategies are discussed. This review aims at sensitizing the reader for recognizing sleep disturbances as a potential contributor to cognitive deficits in several disorders, a fact which is often overlooked up to date.
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Affiliation(s)
- Monique Goerke
- German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany. .,Department of Psychiatry and Psychotherapy, University of Rostock, Gehlsheimer Str. 20, 18147, Rostock, Germany.
| | - Notger G Müller
- German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany
| | - Stefan Cohrs
- Department of Psychiatry and Psychotherapy, University of Rostock, Gehlsheimer Str. 20, 18147, Rostock, Germany
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42
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Formation and Dynamics of Waves in a Cortical Model of Cholinergic Modulation. PLoS Comput Biol 2015; 11:e1004449. [PMID: 26295587 PMCID: PMC4546669 DOI: 10.1371/journal.pcbi.1004449] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 07/16/2015] [Indexed: 12/18/2022] Open
Abstract
Acetylcholine (ACh) is a regulator of neural excitability and one of the neurochemical substrates of sleep. Amongst the cellular effects induced by cholinergic modulation are a reduction in spike-frequency adaptation (SFA) and a shift in the phase response curve (PRC). We demonstrate in a biophysical model how changes in neural excitability and network structure interact to create three distinct functional regimes: localized asynchronous, traveling asynchronous, and traveling synchronous. Our results qualitatively match those observed experimentally. Cortical activity during slow wave sleep (SWS) differs from that during REM sleep or waking states. During SWS there are traveling patterns of activity in the cortex; in other states stationary patterns occur. Our model is a network composed of Hodgkin-Huxley type neurons with a M-current regulated by ACh. Regulation of ACh level can account for dynamical changes between functional regimes. Reduction of the magnitude of this current recreates the reduction in SFA the shift from a type 2 to a type 1 PRC observed in the presence of ACh. When SFA is minimal (in waking or REM sleep state, high ACh) patterns of activity are localized and easily pinned by network inhomogeneities. When SFA is present (decreasing ACh), traveling waves of activity naturally arise. A further decrease in ACh leads to a high degree of synchrony within traveling waves. We also show that the level of ACh determines how sensitive network activity is to synaptic heterogeneity. These regimes may have a profound functional significance as stationary patterns may play a role in the proper encoding of external input as memory and traveling waves could lead to synaptic regularization, giving unique insights into the role and significance of ACh in determining patterns of cortical activity and functional differences arising from the patterns.
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Lajnef T, Chaibi S, Eichenlaub JB, Ruby PM, Aguera PE, Samet M, Kachouri A, Jerbi K. Sleep spindle and K-complex detection using tunable Q-factor wavelet transform and morphological component analysis. Front Hum Neurosci 2015; 9:414. [PMID: 26283943 PMCID: PMC4516876 DOI: 10.3389/fnhum.2015.00414] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 07/06/2015] [Indexed: 12/11/2022] Open
Abstract
A novel framework for joint detection of sleep spindles and K-complex events, two hallmarks of sleep stage S2, is proposed. Sleep electroencephalography (EEG) signals are split into oscillatory (spindles) and transient (K-complex) components. This decomposition is conveniently achieved by applying morphological component analysis (MCA) to a sparse representation of EEG segments obtained by the recently introduced discrete tunable Q-factor wavelet transform (TQWT). Tuning the Q-factor provides a convenient and elegant tool to naturally decompose the signal into an oscillatory and a transient component. The actual detection step relies on thresholding (i) the transient component to reveal K-complexes and (ii) the time-frequency representation of the oscillatory component to identify sleep spindles. Optimal thresholds are derived from ROC-like curves (sensitivity vs. FDR) on training sets and the performance of the method is assessed on test data sets. We assessed the performance of our method using full-night sleep EEG data we collected from 14 participants. In comparison to visual scoring (Expert 1), the proposed method detected spindles with a sensitivity of 83.18% and false discovery rate (FDR) of 39%, while K-complexes were detected with a sensitivity of 81.57% and an FDR of 29.54%. Similar performances were obtained when using a second expert as benchmark. In addition, when the TQWT and MCA steps were excluded from the pipeline the detection sensitivities dropped down to 70% for spindles and to 76.97% for K-complexes, while the FDR rose up to 43.62 and 49.09%, respectively. Finally, we also evaluated the performance of the proposed method on a set of publicly available sleep EEG recordings. Overall, the results we obtained suggest that the TQWT-MCA method may be a valuable alternative to existing spindle and K-complex detection methods. Paths for improvements and further validations with large-scale standard open-access benchmarking data sets are discussed.
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Affiliation(s)
- Tarek Lajnef
- LETI Lab, Sfax National Engineering School, University of SfaxSfax, Tunisia
| | - Sahbi Chaibi
- LETI Lab, Sfax National Engineering School, University of SfaxSfax, Tunisia
| | | | - Perrine M. Ruby
- DYCOG Lab, Lyon Neuroscience Research Center, INSERM U1028, UMR 5292, University Lyon ILyon, France
| | - Pierre-Emmanuel Aguera
- DYCOG Lab, Lyon Neuroscience Research Center, INSERM U1028, UMR 5292, University Lyon ILyon, France
| | - Mounir Samet
- LETI Lab, Sfax National Engineering School, University of SfaxSfax, Tunisia
| | - Abdennaceur Kachouri
- LETI Lab, Sfax National Engineering School, University of SfaxSfax, Tunisia
- Electrical Engineering Department, Higher Institute of Industrial Systems of Gabes, University of GabesGabes, Tunisia
| | - Karim Jerbi
- DYCOG Lab, Lyon Neuroscience Research Center, INSERM U1028, UMR 5292, University Lyon ILyon, France
- Psychology Department, University of MontrealMontreal, QC, Canada
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44
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Lustenberger C, Wehrle F, Tüshaus L, Achermann P, Huber R. The Multidimensional Aspects of Sleep Spindles and Their Relationship to Word-Pair Memory Consolidation. Sleep 2015; 38:1093-103. [PMID: 25845686 DOI: 10.5665/sleep.4820] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 02/18/2015] [Indexed: 11/03/2022] Open
Abstract
STUDY OBJECTIVES Several studies proposed a link between sleep spindles and sleep dependent memory consolidation in declarative learning tasks. In addition to these state-like aspects of sleep spindles, they have also trait-like characteristics, i.e., were related to general cognitive performance, an important distinction that has often been neglected in correlative studies. Furthermore, from the multitude of different sleep spindle measures, often just one specific aspect was analyzed. Thus, we aimed at taking multidimensional aspects of sleep spindles into account when exploring their relationship to word-pair memory consolidation. DESIGN Each subject underwent 2 study nights with all-night high-density electroencephalographic (EEG) recordings. Sleep spindles were automatically detected in all EEG channels. Subjects were trained and tested on a word-pair learning task in the evening, and retested in the morning to assess sleep related memory consolidation (overnight retention). Trait-like aspects refer to the mean of both nights and state-like aspects were calculated as the difference between night 1 and night 2. SETTING Sleep laboratory. PARTICIPANTS Twenty healthy male subjects (age: 23.3 ± 2.1 y). MEASUREMENTS AND RESULTS Overnight retention was negatively correlated with trait-like aspects of fast sleep spindle density and positively with slow spindle density on a global level. In contrast, state-like aspects were observed for integrated slow spindle activity, which was positively related to the differences in overnight retention in specific regions. CONCLUSION Our results demonstrate the importance of a multidimensional approach when investigating the relationship between sleep spindles and memory consolidation and thereby provide a more complete picture explaining divergent findings in the literature.
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Affiliation(s)
- Caroline Lustenberger
- University Children's Hospital Zurich, Child Development Center, Zurich, Switzerland.,Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland
| | - Flavia Wehrle
- University Hospital Zurich, Switzerland.,Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | - Laura Tüshaus
- University of Zurich, Institute of Pharmacology and Toxicology, Zurich, Switzerland.,Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland
| | - Peter Achermann
- University of Zurich, Institute of Pharmacology and Toxicology, Zurich, Switzerland.,Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland.,Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.,Zurich Center for Interdisciplinary Sleep Research, University of Zurich, Zurich, Switzerland
| | - Reto Huber
- University Children's Hospital Zurich, Child Development Center, Zurich, Switzerland.,University Children's Hospital Zurich, Children Research Center, Switzerland.,Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland.,Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.,Zurich Center for Interdisciplinary Sleep Research, University of Zurich, Zurich, Switzerland.,University Clinics for Child and Adolescent Psychiatry, Zurich, Switzerland
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45
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Mantua J, Mahan KM, Henry OS, Spencer RMC. Altered sleep composition after traumatic brain injury does not affect declarative sleep-dependent memory consolidation. Front Hum Neurosci 2015; 9:328. [PMID: 26097451 PMCID: PMC4456580 DOI: 10.3389/fnhum.2015.00328] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 05/21/2015] [Indexed: 11/21/2022] Open
Abstract
Individuals with a history of traumatic brain injury (TBI) often report sleep disturbances, which may be caused by changes in sleep architecture or reduced sleep quality (greater time awake after sleep onset, poorer sleep efficiency, and sleep stage proportion alterations). Sleep is beneficial for memory formation, and herein we examine whether altered sleep physiology following TBI has deleterious effects on sleep-dependent declarative memory consolidation. Participants learned a list of word pairs in the morning or evening, and recall was assessed 12-h later, following an interval awake or with overnight sleep. Young adult participants (18–22 years) were assigned to one of four experimental groups: TBI Sleep (n = 14), TBI Wake (n = 12), non-TBI Sleep (n = 15), non-TBI Wake (n = 15). Each TBI participant was >1 year post-injury. Sleep physiology was measured with polysomnography. Memory consolidation was assessed by comparing change in word-pair recall over 12-h intersession intervals. The TBI group spent a significantly greater proportion of the night in SWS than the non-TBI group at the expense of NREM1. The TBI group also had marginally lower EEG delta power during SWS in the central region. Intersession changes in recall were greater for intervals with sleep than without sleep in both groups. However, despite abnormal sleep stage proportions for individuals with a TBI history, there was no difference in the intersession change in recall following sleep for the TBI and non-TBI groups. In both Sleep groups combined, there was a positive correlation between Intersession Change and the proportion of the night in NREM2 + SWS. Overall, sleep composition is altered following TBI but such deficits do not yield insufficiencies in sleep-dependent memory consolidation.
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Affiliation(s)
- Janna Mantua
- Neuroscience and Behavior Program, University of Massachusetts Amherst, MA, USA
| | - Keenan M Mahan
- Commonwealth Honors College, University of Massachusetts Amherst, MA, USA
| | - Owen S Henry
- Commonwealth Honors College, University of Massachusetts Amherst, MA, USA
| | - Rebecca M C Spencer
- Neuroscience and Behavior Program, University of Massachusetts Amherst, MA, USA ; Department of Psychological and Brain Sciences, University of Massachusetts Amherst, MA, USA
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46
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Feld GB, Diekelmann S. Sleep smart-optimizing sleep for declarative learning and memory. Front Psychol 2015; 6:622. [PMID: 26029150 PMCID: PMC4428077 DOI: 10.3389/fpsyg.2015.00622] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 04/27/2015] [Indexed: 02/05/2023] Open
Abstract
The last decade has witnessed a spurt of new publications documenting sleep's essential contribution to the brains ability to form lasting memories. For the declarative memory domain, slow wave sleep (the deepest sleep stage) has the greatest beneficial effect on the consolidation of memories acquired during preceding wakefulness. The finding that newly encoded memories become reactivated during subsequent sleep fostered the idea that reactivation leads to the strengthening and transformation of the memory trace. According to the active system consolidation account, trace reactivation leads to the redistribution of the transient memory representations from the hippocampus to the long-lasting knowledge networks of the cortex. Apart from consolidating previously learned information, sleep also facilitates the encoding of new memories after sleep, which probably relies on the renormalization of synaptic weights during sleep as suggested by the synaptic homeostasis theory. During wakefulness overshooting potentiation causes an imbalance in synaptic weights that is countered by synaptic downscaling during subsequent sleep. This review briefly introduces the basic concepts and central findings of the research on sleep and memory, and discusses implications of this lab-based work for everyday applications to make the best possible use of sleep's beneficial effect on learning and memory.
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Affiliation(s)
- Gordon B Feld
- Institute for Medical Psychology and Behavioral Neurobiology, University of Tübingen Tübingen, Germany
| | - Susanne Diekelmann
- Institute for Medical Psychology and Behavioral Neurobiology, University of Tübingen Tübingen, Germany
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47
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Bellesi M, Riedner BA, Garcia-Molina GN, Cirelli C, Tononi G. Enhancement of sleep slow waves: underlying mechanisms and practical consequences. Front Syst Neurosci 2014; 8:208. [PMID: 25389394 PMCID: PMC4211398 DOI: 10.3389/fnsys.2014.00208] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 10/02/2014] [Indexed: 02/06/2023] Open
Abstract
Even modest sleep restriction, especially the loss of sleep slow wave activity (SWA), is invariably associated with slower electroencephalogram (EEG) activity during wake, the occurrence of local sleep in an otherwise awake brain, and impaired performance due to cognitive and memory deficits. Recent studies not only confirm the beneficial role of sleep in memory consolidation, but also point to a specific role for sleep slow waves. Thus, the implementation of methods to enhance sleep slow waves without unwanted arousals or lightening of sleep could have significant practical implications. Here we first review the evidence that it is possible to enhance sleep slow waves in humans using transcranial direct-current stimulation (tDCS) and transcranial magnetic stimulation. Since these methods are currently impractical and their safety is questionable, especially for chronic long-term exposure, we then discuss novel data suggesting that it is possible to enhance slow waves using sensory stimuli. We consider the physiology of the K-complex (KC), a peripheral evoked slow wave, and show that, among different sensory modalities, acoustic stimulation is the most effective in increasing the magnitude of slow waves, likely through the activation of non-lemniscal ascending pathways to the thalamo-cortical system. In addition, we discuss how intensity and frequency of the acoustic stimuli, as well as exact timing and pattern of stimulation, affect sleep enhancement. Finally, we discuss automated algorithms that read the EEG and, in real-time, adjust the stimulation parameters in a closed-loop manner to obtain an increase in sleep slow waves and avoid undesirable arousals. In conclusion, while discussing the mechanisms that underlie the generation of sleep slow waves, we review the converging evidence showing that acoustic stimulation is safe and represents an ideal tool for slow wave sleep (SWS) enhancement.
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Affiliation(s)
- Michele Bellesi
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, USA
| | - Brady A. Riedner
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, USA
| | - Gary N. Garcia-Molina
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, USA
- Clinical Sites Research Program, Philips Group InnovationBriarcliff, NY, USA
| | - Chiara Cirelli
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, USA
| | - Giulio Tononi
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, USA
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48
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Abstract
Sleep benefits memory consolidation. Previous theoretical accounts have proposed a differential role of slow-wave sleep (SWS), rapid-eye-movement (REM) sleep, and stage N2 sleep for different types of memories. For example the dual process hypothesis proposes that SWS is beneficial for declarative memories, whereas REM sleep is important for consolidation of non-declarative, procedural and emotional memories. In fact, numerous recent studies do provide further support for the crucial role of SWS (or non-REM sleep) in declarative memory consolidation. However, recent evidence for the benefit of REM sleep for non-declarative memories is rather scarce. In contrast, several recent studies have related consolidation of procedural memories (and some also emotional memories) to SWS (or non-REM sleep)-dependent consolidation processes. We will review this recent evidence, and propose future research questions to advance our understanding of the role of different sleep stages for memory consolidation.
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49
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Gardner RJ, Kersanté F, Jones MW, Bartsch U. Neural oscillations during non-rapid eye movement sleep as biomarkers of circuit dysfunction in schizophrenia. Eur J Neurosci 2014; 39:1091-106. [DOI: 10.1111/ejn.12533] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Revised: 01/06/2014] [Accepted: 01/29/2014] [Indexed: 12/25/2022]
Affiliation(s)
- Richard J. Gardner
- School of Physiology and Pharmacology; University of Bristol; Medical Sciences Building University Walk Bristol BS8 1TD UK
| | - Flavie Kersanté
- School of Physiology and Pharmacology; University of Bristol; Medical Sciences Building University Walk Bristol BS8 1TD UK
| | - Matthew W. Jones
- School of Physiology and Pharmacology; University of Bristol; Medical Sciences Building University Walk Bristol BS8 1TD UK
| | - Ullrich Bartsch
- School of Physiology and Pharmacology; University of Bristol; Medical Sciences Building University Walk Bristol BS8 1TD UK
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50
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Abstract
Sleep is essential for effective cognitive functioning. Loosing even a few hours of sleep can have detrimental effects on a wide variety of cognitive processes such as attention, language, reasoning, decision making, learning and memory. While sleep is necessary to ensure normal healthy cognitive functioning, it can also enhance performance beyond the boundaries of the normal condition. This article discusses the enhancing potential of sleep, mainly focusing on the domain of learning and memory. Sleep is known to facilitate the consolidation of memories learned before sleep as well as the acquisition of new memories to be learned after sleep. According to a widely held model this beneficial effect of sleep relies on the neuronal reactivation of memories during sleep that is associated with sleep-specific brain oscillations (slow oscillations, spindles, ripples) as well as a characteristic neurotransmitter milieu. Recent research indicates that memory processing during sleep can be boosted by (i) cueing memory reactivation during sleep; (ii) stimulating sleep-specific brain oscillations; and (iii) targeting specific neurotransmitter systems pharmacologically. Olfactory and auditory cues can be used, for example, to increase reactivation of associated memories during post-learning sleep. Intensifying neocortical slow oscillations (the hallmark of slow wave sleep (SWS)) by electrical or auditory stimulation and modulating specific neurotransmitters such as noradrenaline and glutamate likewise facilitates memory processing during sleep. With this evidence in mind, this article concludes by discussing different methodological caveats and ethical issues that should be considered when thinking about using sleep for cognitive enhancement in everyday applications.
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Affiliation(s)
- Susanne Diekelmann
- Institute of Medical Psychology and Behavioral Neurobiology, University Tübingen Tübingen, Germany
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