1
|
Leach S, Krugliakova E, Sousouri G, Snipes S, Skorucak J, Schühle S, Müller M, Ferster ML, Da Poian G, Karlen W, Huber R. Acoustically evoked K-complexes together with sleep spindles boost verbal declarative memory consolidation in healthy adults. Sci Rep 2024; 14:19184. [PMID: 39160150 PMCID: PMC11333484 DOI: 10.1038/s41598-024-67701-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 07/15/2024] [Indexed: 08/21/2024] Open
Abstract
Over the past decade, phase-targeted auditory stimulation (PTAS), a neuromodulation approach which presents auditory stimuli locked to the ongoing phase of slow waves during sleep, has shown potential to enhance specific aspects of sleep functions. However, the complexity of PTAS responses complicates the establishment of causality between specific electroencephalographic events and observed benefits. Here, we used down-PTAS during sleep to specifically evoke the early, K-complex (KC)-like response following PTAS without leading to a sustained increase in slow-wave activity throughout the stimulation window. Over the course of two nights, one with down-PTAS, the other without, high-density electroencephalography (hd-EEG) was recorded from 14 young healthy adults. The early response exhibited striking similarities to evoked KCs and was associated with improved verbal memory consolidation via stimulus-evoked spindle events nested into the up-phase of ongoing 1 Hz waves in a central region. These findings suggest that the early, KC-like response is sufficient to boost memory, potentially by orchestrating aspects of the hippocampal-neocortical dialogue.
Collapse
Affiliation(s)
- Sven Leach
- Child Development Centre and Children's Research Centre, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Elena Krugliakova
- Child Development Centre and Children's Research Centre, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, Netherlands
| | - Georgia Sousouri
- Child Development Centre and Children's Research Centre, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
- Mobile Health Systems Lab, Department of Health Sciences and Technology, Institute of Robotics and Intelligent Systems, ETH Zurich, Zurich, Switzerland
- Institute of Pharmacology & Toxicology, University of Zurich, Zurich, Switzerland
| | - Sophia Snipes
- Child Development Centre and Children's Research Centre, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Jelena Skorucak
- Child Development Centre and Children's Research Centre, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Selina Schühle
- Child Development Centre and Children's Research Centre, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Manuel Müller
- Child Development Centre and Children's Research Centre, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Maria Laura Ferster
- Mobile Health Systems Lab, Department of Health Sciences and Technology, Institute of Robotics and Intelligent Systems, ETH Zurich, Zurich, Switzerland
| | - Giulia Da Poian
- Sensory-Motor Systems Lab, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Walter Karlen
- Mobile Health Systems Lab, Department of Health Sciences and Technology, Institute of Robotics and Intelligent Systems, ETH Zurich, Zurich, Switzerland
- Institute of Biomedical Engineering, Faculty of Engineering, Computer Science and Psychology, Ulm University, Ulm, Germany
| | - Reto Huber
- Child Development Centre and Children's Research Centre, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland.
- Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
| |
Collapse
|
2
|
Mushtaq M, Marshall L, ul Haq R, Martinetz T. Possible mechanisms to improve sleep spindles via closed loop stimulation during slow wave sleep: A computational study. PLoS One 2024; 19:e0306218. [PMID: 38924001 PMCID: PMC11207127 DOI: 10.1371/journal.pone.0306218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 06/12/2024] [Indexed: 06/28/2024] Open
Abstract
Sleep spindles are one of the prominent EEG oscillatory rhythms of non-rapid eye movement sleep. In the memory consolidation, these oscillations have an important role in the processes of long-term potentiation and synaptic plasticity. Moreover, the activity (spindle density and/or sigma power) of spindles has a linear association with learning performance in different paradigms. According to the experimental observations, the sleep spindle activity can be improved by closed loop acoustic stimulations (CLAS) which eventually improve memory performance. To examine the effects of CLAS on spindles, we propose a biophysical thalamocortical model for slow oscillations (SOs) and sleep spindles. In addition, closed loop stimulation protocols are applied on a thalamic network. Our model results show that the power of spindles is increased when stimulation cues are applied at the commencing of an SO Down-to-Up-state transition, but that activity gradually decreases when cues are applied with an increased time delay from this SO phase. Conversely, stimulation is not effective when cues are applied during the transition of an Up-to-Down-state. Furthermore, our model suggests that a strong inhibitory input from the reticular (RE) layer to the thalamocortical (TC) layer in the thalamic network shifts leads to an emergence of spindle activity at the Up-to-Down-state transition (rather than at Down-to-Up-state transition), and the spindle frequency is also reduced (8-11 Hz) by thalamic inhibition.
Collapse
Affiliation(s)
| | - Lisa Marshall
- Institute of Experimental and Clinical Pharmacology, University of Lübeck, Lübeck, Germany
- Center of Brain, Behavior and Metabolism, Lübeck, Germany
- University Clinic Hospital Schleswig Holstein, Lübeck, Germany
| | - Rizwan ul Haq
- Department of Pharmacy, Abbottabad University of Science and Technology, Abbottabad, Pakistan
| | - Thomas Martinetz
- Institute for Neuro- and Bioinformatics, Lübeck, Germany
- Center of Brain, Behavior and Metabolism, Lübeck, Germany
| |
Collapse
|
3
|
Hebron H, Lugli B, Dimitrova R, Jaramillo V, Yeh LR, Rhodes E, Grossman N, Dijk DJ, Violante IR. A closed-loop auditory stimulation approach selectively modulates alpha oscillations and sleep onset dynamics in humans. PLoS Biol 2024; 22:e3002651. [PMID: 38889194 PMCID: PMC11185466 DOI: 10.1371/journal.pbio.3002651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 05/01/2024] [Indexed: 06/20/2024] Open
Abstract
Alpha oscillations play a vital role in managing the brain's resources, inhibiting neural activity as a function of their phase and amplitude, and are changed in many brain disorders. Developing minimally invasive tools to modulate alpha activity and identifying the parameters that determine its response to exogenous modulators is essential for the implementation of focussed interventions. We introduce Alpha Closed-Loop Auditory Stimulation (αCLAS) as an EEG-based method to modulate and investigate these brain rhythms in humans with specificity and selectivity, using targeted auditory stimulation. Across a series of independent experiments, we demonstrate that αCLAS alters alpha power, frequency, and connectivity in a phase, amplitude, and topography-dependent manner. Using single-pulse-αCLAS, we show that the effects of auditory stimuli on alpha oscillations can be explained within the theoretical framework of oscillator theory and a phase-reset mechanism. Finally, we demonstrate the functional relevance of our approach by showing that αCLAS can interfere with sleep onset dynamics in a phase-dependent manner.
Collapse
Affiliation(s)
- Henry Hebron
- School of Psychology, University of Surrey, Guildford, United Kingdom
- Surrey Sleep Research Centre, University of Surrey, Guildford, United Kingdom
- UK Dementia Research Institute Care Research and Technology Centre, Imperial College London and the University of Surrey, Guildford, United Kingdom
| | - Beatrice Lugli
- School of Psychology, University of Surrey, Guildford, United Kingdom
| | - Radost Dimitrova
- School of Psychology, University of Surrey, Guildford, United Kingdom
| | - Valeria Jaramillo
- School of Psychology, University of Surrey, Guildford, United Kingdom
- Surrey Sleep Research Centre, University of Surrey, Guildford, United Kingdom
- UK Dementia Research Institute Care Research and Technology Centre, Imperial College London and the University of Surrey, Guildford, United Kingdom
| | - Lisa R. Yeh
- School of Psychology, University of Surrey, Guildford, United Kingdom
| | - Edward Rhodes
- Department of Brain Sciences, Imperial College London, London, United Kingdom
- UK Dementia Research Institute Imperial College London, United Kingdom
| | - Nir Grossman
- Department of Brain Sciences, Imperial College London, London, United Kingdom
- UK Dementia Research Institute Imperial College London, United Kingdom
| | - Derk-Jan Dijk
- Surrey Sleep Research Centre, University of Surrey, Guildford, United Kingdom
- UK Dementia Research Institute Care Research and Technology Centre, Imperial College London and the University of Surrey, Guildford, United Kingdom
| | - Ines R. Violante
- School of Psychology, University of Surrey, Guildford, United Kingdom
| |
Collapse
|
4
|
Aksamaz S, Mölle M, Akinola EO, Gromodka E, Bazhenov M, Marshall L. Single closed-loop acoustic stimulation targeting memory consolidation suppressed hippocampal ripple and thalamo-cortical spindle activity in mice. Eur J Neurosci 2024; 59:595-612. [PMID: 37605315 PMCID: PMC11214843 DOI: 10.1111/ejn.16116] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 06/20/2023] [Accepted: 07/24/2023] [Indexed: 08/23/2023]
Abstract
Brain rhythms of sleep reflect neuronal activity underlying sleep-associated memory consolidation. The modulation of brain rhythms, such as the sleep slow oscillation (SO), is used both to investigate neurophysiological mechanisms as well as to measure the impact of sleep on presumed functional correlates. Previously, closed-loop acoustic stimulation in humans targeted to the SO Up-state successfully enhanced the slow oscillation rhythm and phase-dependent spindle activity, although effects on memory retention have varied. Here, we aim to disclose relations between stimulation-induced hippocampo-thalamo-cortical activity and retention performance on a hippocampus-dependent object-place recognition task in mice by applying acoustic stimulation at four estimated SO phases compared to sham condition. Across the 3-h retention interval at the beginning of the light phase closed-loop stimulation failed to improve retention significantly over sham. However, retention during SO Up-state stimulation was significantly higher than for another SO phase. At all SO phases, acoustic stimulation was accompanied by a sharp increase in ripple activity followed by about a second-long suppression of hippocampal sharp wave ripple and longer maintained suppression of thalamo-cortical spindle activity. Importantly, dynamics of SO-coupled hippocampal ripple activity distinguished SOUp-state stimulation. Non-rapid eye movement (NREM) sleep was not impacted by stimulation, yet preREM sleep duration was effected. Results reveal the complex effect of stimulation on the brain dynamics and support the use of closed-loop acoustic stimulation in mice to investigate the inter-regional mechanisms underlying memory consolidation.
Collapse
Affiliation(s)
- Sonat Aksamaz
- Institute of Experimental and Clinical Pharmacology,
University of Lübeck, Lübeck, Germany
- University Medical Center Schleswig-Holstein,
Lübeck, Germany
| | - Matthias Mölle
- University Medical Center Schleswig-Holstein,
Lübeck, Germany
- Center of Brain, Behavior and Metabolism, Lübeck,
Germany
| | - Esther Olubukola Akinola
- Institute of Experimental and Clinical Pharmacology,
University of Lübeck, Lübeck, Germany
- University Medical Center Schleswig-Holstein,
Lübeck, Germany
| | - Erik Gromodka
- Institute of Experimental and Clinical Pharmacology,
University of Lübeck, Lübeck, Germany
| | - Maxim Bazhenov
- Department of Medicine, University of California San Diego,
La Jolla, CA, USA
| | - Lisa Marshall
- Institute of Experimental and Clinical Pharmacology,
University of Lübeck, Lübeck, Germany
- University Medical Center Schleswig-Holstein,
Lübeck, Germany
- Center of Brain, Behavior and Metabolism, Lübeck,
Germany
| |
Collapse
|
5
|
Schreiner T, Petzka M, Staudigl T, Staresina BP. Respiration modulates sleep oscillations and memory reactivation in humans. Nat Commun 2023; 14:8351. [PMID: 38110418 PMCID: PMC10728072 DOI: 10.1038/s41467-023-43450-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 11/09/2023] [Indexed: 12/20/2023] Open
Abstract
The beneficial effect of sleep on memory consolidation relies on the precise interplay of slow oscillations and spindles. However, whether these rhythms are orchestrated by an underlying pacemaker has remained elusive. Here, we tested the relationship between respiration, which has been shown to impact brain rhythms and cognition during wake, sleep-related oscillations and memory reactivation in humans. We re-analysed an existing dataset, where scalp electroencephalography and respiration were recorded throughout an experiment in which participants (N = 20) acquired associative memories before taking a nap. Our results reveal that respiration modulates the emergence of sleep oscillations. Specifically, slow oscillations, spindles as well as their interplay (i.e., slow-oscillation_spindle complexes) systematically increase towards inhalation peaks. Moreover, the strength of respiration - slow-oscillation_spindle coupling is linked to the extent of memory reactivation (i.e., classifier evidence in favour of the previously learned stimulus category) during slow-oscillation_spindles. Our results identify a clear association between respiration and memory consolidation in humans and highlight the role of brain-body interactions during sleep.
Collapse
Affiliation(s)
- Thomas Schreiner
- Department of Psychology, Ludwig-Maximilians-Universität München, München, Germany.
| | - Marit Petzka
- Max Planck Institute for Human Development, Berlin, Germany
- Institute of Psychology, University of Hamburg, Hamburg, Germany
| | - Tobias Staudigl
- Department of Psychology, Ludwig-Maximilians-Universität München, München, Germany
| | - Bernhard P Staresina
- Department of Experimental Psychology, University of Oxford, Oxford, UK.
- Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford, UK.
| |
Collapse
|
6
|
Wunderlin M, Zeller CJ, Senti SR, Fehér KD, Suppiger D, Wyss P, Koenig T, Teunissen CE, Nissen C, Klöppel S, Züst MA. Acoustic stimulation during sleep predicts long-lasting increases in memory performance and beneficial amyloid response in older adults. Age Ageing 2023; 52:afad228. [PMID: 38163288 PMCID: PMC10758173 DOI: 10.1093/ageing/afad228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Indexed: 01/03/2024] Open
Abstract
BACKGROUND Sleep and neurodegeneration are assumed to be locked in a bi-directional vicious cycle. Improving sleep could break this cycle and help to prevent neurodegeneration. We tested multi-night phase-locked acoustic stimulation (PLAS) during slow wave sleep (SWS) as a non-invasive method to improve SWS, memory performance and plasma amyloid levels. METHODS 32 healthy older adults (agemean: 68.9) completed a between-subject sham-controlled three-night intervention, preceded by a sham-PLAS baseline night. RESULTS PLAS induced increases in sleep-associated spectral-power bands as well as a 24% increase in slow wave-coupled spindles, known to support memory consolidation. There was no significant group-difference in memory performance or amyloid-beta between the intervention and control group. However, the magnitude of PLAS-induced physiological responses were associated with memory performance up to 3 months post intervention and beneficial changes in plasma amyloid. Results were exclusive to the intervention group. DISCUSSION Multi-night PLAS is associated with long-lasting benefits in memory and metabolite clearance in older adults, rendering PLAS a promising tool to build upon and develop long-term protocols for the prevention of cognitive decline.
Collapse
Affiliation(s)
- Marina Wunderlin
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland
- Graduate School for Health Sciences, University of Bern, 3012 Bern, Switzerland
| | - Céline Jacqueline Zeller
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland
- Graduate School for Health Sciences, University of Bern, 3012 Bern, Switzerland
| | - Samira Rafaela Senti
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland
| | - Kristoffer Daniel Fehér
- University Hospital of Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland
| | - Debora Suppiger
- Department of Neonatology, University Hospital Zurich and University of Zurich, 8006 Zürich, Switzerland
| | - Patric Wyss
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland
| | - Thomas Koenig
- University Hospital of Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland
| | - Charlotte Elisabeth Teunissen
- Neurochemistry Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, Neurodegeneration, Amsterdam UMC, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, Netherlands
| | - Christoph Nissen
- University Hospital of Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland
- Division of Psychiatric Specialties, Geneva University Hospitals (HUG), 1205 Geneva, Switzerland
| | - Stefan Klöppel
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland
| | - Marc Alain Züst
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland
| |
Collapse
|
7
|
Baxter BS, Mylonas D, Kwok KS, Talbot CE, Patel R, Zhu L, Vangel M, Stickgold R, Manoach DS. The effects of closed-loop auditory stimulation on sleep oscillatory dynamics in relation to motor procedural memory consolidation. Sleep 2023; 46:zsad206. [PMID: 37531587 PMCID: PMC11009689 DOI: 10.1093/sleep/zsad206] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 05/13/2023] [Indexed: 08/04/2023] Open
Abstract
STUDY OBJECTIVES Healthy aging and many disorders show reduced sleep-dependent memory consolidation and corresponding alterations in non-rapid eye movement sleep oscillations. Yet sleep physiology remains a relatively neglected target for improving memory. We evaluated the effects of closed-loop auditory stimulation during sleep (CLASS) on slow oscillations (SOs), sleep spindles, and their coupling, all in relation to motor procedural memory consolidation. METHODS Twenty healthy young adults had two afternoon naps: one with auditory stimulation during SO upstates and another with no stimulation. Twelve returned for a third nap with stimulation at variable times in relation to SO upstates. In all sessions, participants trained on the motor sequence task prior to napping and were tested afterward. RESULTS Relative to epochs with no stimulation, upstate stimuli disrupted sleep and evoked SOs, spindles, and SO-coupled spindles. Stimuli that successfully evoked oscillations were delivered closer to the peak of the SO upstate and when spindle power was lower than stimuli that failed to evoke oscillations. Across conditions, participants showed similar significant post-nap performance improvement that correlated with the density of SO-coupled spindles. CONCLUSIONS Despite its strong effects on sleep physiology, CLASS failed to enhance motor procedural memory. Our findings suggest methods to overcome this failure, including better sound calibration to preserve sleep continuity and the use of real-time predictive algorithms to more precisely target SO upstates and to avoid disrupting endogenous SO-coupled spindles and their mnemonic function. They motivate continued development of CLASS as an intervention to manipulate sleep oscillatory dynamics and improve memory.
Collapse
Affiliation(s)
- Bryan S Baxter
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
| | - Dimitrios Mylonas
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
| | - Kristi S Kwok
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Christine E Talbot
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Rudra Patel
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Lin Zhu
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Mark Vangel
- Department of Biostatistics, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Robert Stickgold
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Dara S Manoach
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
| |
Collapse
|
8
|
Esfahani MJ, Farboud S, Ngo HVV, Schneider J, Weber FD, Talamini LM, Dresler M. Closed-loop auditory stimulation of sleep slow oscillations: Basic principles and best practices. Neurosci Biobehav Rev 2023; 153:105379. [PMID: 37660843 DOI: 10.1016/j.neubiorev.2023.105379] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 08/25/2023] [Accepted: 08/30/2023] [Indexed: 09/05/2023]
Abstract
Sleep is essential for our physical and mental well-being. During sleep, despite the paucity of overt behavior, our brain remains active and exhibits a wide range of coupled brain oscillations. In particular slow oscillations are characteristic for sleep, however whether they are directly involved in the functions of sleep, or are mere epiphenomena, is not yet fully understood. To disentangle the causality of these relationships, experiments utilizing techniques to detect and manipulate sleep oscillations in real-time are essential. In this review, we first overview the theoretical principles of closed-loop auditory stimulation (CLAS) as a method to study the role of slow oscillations in the functions of sleep. We then describe technical guidelines and best practices to perform CLAS and analyze results from such experiments. We further provide an overview of how CLAS has been used to investigate the causal role of slow oscillations in various sleep functions. We close by discussing important caveats, open questions, and potential topics for future research.
Collapse
Affiliation(s)
| | - Soha Farboud
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, the Netherlands
| | - Hong-Viet V Ngo
- Department of Psychology, University of Essex, United Kingdom; Department of Psychology, University of Lübeck, Germany; Center for Brain, Behaviour and Metabolism, University of Lübeck, Germany
| | - Jules Schneider
- Department of Psychiatry and Psychotherapy, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany; Department of Neurology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany
| | - Frederik D Weber
- Donders Institute for Brain, Cognition and Behaviour, Radboudumc, the Netherlands; Department of Sleep and Cognition, Netherlands Institute for Neuroscience, an institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
| | - Lucia M Talamini
- Department of Psychology, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Brain and Cognition, University of Amsterdam, Amsterdam, the Netherlands
| | - Martin Dresler
- Donders Institute for Brain, Cognition and Behaviour, Radboudumc, the Netherlands.
| |
Collapse
|
9
|
Geva-Sagiv M, Mankin EA, Eliashiv D, Epstein S, Cherry N, Kalender G, Tchemodanov N, Nir Y, Fried I. Augmenting hippocampal-prefrontal neuronal synchrony during sleep enhances memory consolidation in humans. Nat Neurosci 2023:10.1038/s41593-023-01324-5. [PMID: 37264156 DOI: 10.1038/s41593-023-01324-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 04/06/2023] [Indexed: 06/03/2023]
Abstract
Memory consolidation during sleep is thought to depend on the coordinated interplay between cortical slow waves, thalamocortical sleep spindles and hippocampal ripples, but direct evidence is lacking. Here, we implemented real-time closed-loop deep brain stimulation in human prefrontal cortex during sleep and tested its effects on sleep electrophysiology and on overnight consolidation of declarative memory. Synchronizing the stimulation to the active phases of endogenous slow waves in the medial temporal lobe (MTL) enhanced sleep spindles, boosted locking of brain-wide neural spiking activity to MTL slow waves, and improved coupling between MTL ripples and thalamocortical oscillations. Furthermore, synchronized stimulation enhanced the accuracy of recognition memory. By contrast, identical stimulation without this precise time-locking was not associated with, and sometimes even degraded, these electrophysiological and behavioral effects. Notably, individual changes in memory accuracy were highly correlated with electrophysiological effects. Our results indicate that hippocampo-thalamocortical synchronization during sleep causally supports human memory consolidation.
Collapse
Affiliation(s)
- Maya Geva-Sagiv
- Department of Neurosurgery, University of California, Los Angeles, Los Angeles, CA, USA
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- Center of Neuroscience, University of California, Davis, Davis, CA, USA
| | - Emily A Mankin
- Department of Neurosurgery, University of California, Los Angeles, Los Angeles, CA, USA
| | - Dawn Eliashiv
- Department of Neurology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Shdema Epstein
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Natalie Cherry
- Department of Neurosurgery, University of California, Los Angeles, Los Angeles, CA, USA
| | - Guldamla Kalender
- Department of Neurosurgery, University of California, Los Angeles, Los Angeles, CA, USA
| | - Natalia Tchemodanov
- Department of Neurosurgery, University of California, Los Angeles, Los Angeles, CA, USA
| | - Yuval Nir
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel.
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel.
| | - Itzhak Fried
- Department of Neurosurgery, University of California, Los Angeles, Los Angeles, CA, USA.
| |
Collapse
|
10
|
Abstract
The restorative function of sleep is shaped by its duration, timing, continuity, subjective quality, and efficiency. Current sleep recommendations specify only nocturnal duration and have been largely derived from sleep self-reports that can be imprecise and miss relevant details. Sleep duration, preferred timing, and ability to withstand sleep deprivation are heritable traits whose expression may change with age and affect the optimal sleep prescription for an individual. Prevailing societal norms and circumstances related to work and relationships interact to influence sleep opportunity and quality. The value of allocating time for sleep is revealed by the impact of its restriction on behavior, functional brain imaging, sleep macrostructure, and late-life cognition. Augmentation of sleep slow oscillations and spindles have been proposed for enhancing sleep quality, but they inconsistently achieve their goal. Crafting bespoke sleep recommendations could benefit from large-scale, longitudinal collection of objective sleep data integrated with behavioral and self-reported data.
Collapse
Affiliation(s)
- Ruth L F Leong
- Centre for Sleep and Cognition, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; ,
| | - Michael W L Chee
- Centre for Sleep and Cognition, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; ,
| |
Collapse
|
11
|
Wilson DA, Fleming G, Williams CRO, Teixeira CM, Smiley JF, Saito M. Somatostatin neuron contributions to cortical slow wave dysfunction in adult mice exposed to developmental ethanol. Front Neurosci 2023; 17:1127711. [PMID: 37021136 PMCID: PMC10067632 DOI: 10.3389/fnins.2023.1127711] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 03/06/2023] [Indexed: 04/07/2023] Open
Abstract
Introduction Transitions between sleep and waking and sleep-dependent cortical oscillations are heavily dependent on GABAergic neurons. Importantly, GABAergic neurons are especially sensitive to developmental ethanol exposure, suggesting a potential unique vulnerability of sleep circuits to early ethanol. In fact, developmental ethanol exposure can produce long-lasting impairments in sleep, including increased sleep fragmentation and decreased delta wave amplitude. Here, we assessed the efficacy of optogenetic manipulations of somatostatin (SST) GABAergic neurons in the neocortex of adult mice exposed to saline or ethanol on P7, to modulate cortical slow-wave physiology. Methods SST-cre × Ai32 mice, which selectively express channel rhodopsin in SST neurons, were exposed to ethanol or saline on P7. This line expressed similar developmental ethanol induced loss of SST cortical neurons and sleep impairments as C57BL/6By mice. As adults, optical fibers were implanted targeting the prefrontal cortex (PFC) and telemetry electrodes were implanted in the neocortex to monitor slow-wave activity and sleep-wake states. Results Optical stimulation of PFC SST neurons evoked slow-wave potentials and long-latency single-unit excitation in saline treated mice but not in ethanol mice. Closed-loop optogenetic stimulation of PFC SST neuron activation on spontaneous slow-waves enhanced cortical delta oscillations, and this manipulation was more effective in saline mice than P7 ethanol mice. Discussion Together, these results suggest that SST cortical neurons may contribute to slow-wave impairment after developmental ethanol.
Collapse
Affiliation(s)
- Donald A Wilson
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, United States
- Department of Child and Adolescent Psychiatry, New York University School of Medicine, New York, NY, United States
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, United States
| | - G Fleming
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, United States
| | - C R O Williams
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, United States
| | - C M Teixeira
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, United States
- Department of Child and Adolescent Psychiatry, New York University School of Medicine, New York, NY, United States
| | - J F Smiley
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, United States
- Department of Psychiatry, New York University School of Medicine, New York, NY, United States
| | - Mariko Saito
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, United States
- Department of Psychiatry, New York University School of Medicine, New York, NY, United States
| |
Collapse
|
12
|
Ruch S, Schmidig FJ, Knüsel L, Henke K. Closed-loop modulation of local slow oscillations in human NREM sleep. Neuroimage 2022; 264:119682. [PMID: 36240988 DOI: 10.1016/j.neuroimage.2022.119682] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 11/07/2022] Open
Abstract
Slow-wave sleep is the deep non-rapid eye-movement (NREM) sleep stage that is most relevant for the recuperative function of sleep. Its defining property is the presence of slow oscillations (<2 Hz) in the scalp electroencephalogram (EEG). Slow oscillations are generated by a synchronous back and forth between highly active UP-states and silent DOWN-states in neocortical neurons. Growing evidence suggests that closed-loop sensory stimulation targeted at UP-states of EEG-defined slow oscillations can enhance the slow oscillatory activity, increase sleep depth, and boost sleep's recuperative functions. However, several studies failed to replicate such findings. Failed replications might be due to the use of conventional closed-loop stimulation algorithms that analyze the signal from one single electrode and thereby neglect the fact that slow oscillations vary with respect to their origins, distributions, and trajectories on the scalp. In particular, conventional algorithms nonspecifically target functionally heterogeneous UP-states of distinct origins. After all, slow oscillations at distinct sites of the scalp have been associated with distinct functions. Here we present a novel EEG-based closed-loop stimulation algorithm that allows targeting UP- and DOWN-states of distinct cerebral origins based on topographic analyses of the EEG: the topographic targeting of slow oscillations (TOPOSO) algorithm. We present evidence that the TOPOSO algorithm can detect and target local slow oscillations with specific, predefined voltage maps on the scalp in real-time. When compared to a more conventional, single-channel-based approach, TOPOSO leads to fewer but locally more specific stimulations in a simulation study. In a validation study with napping participants, TOPOSO targets auditory stimulation reliably at local UP-states over frontal, sensorimotor, and centro-parietal regions. Importantly, auditory stimulation temporarily enhanced the targeted local state. However, stimulation then elicited a standard frontal slow oscillation rather than local slow oscillations. The TOPOSO algorithm is suitable for the modulation and the study of the functions of local slow oscillations.
Collapse
Affiliation(s)
- Simon Ruch
- Institute for Neuromodulation and Neurotechnology, Department of Neurosurgery and Neurotechnology, University Hospital and University of Tuebingen, Otfried-Müller-Str. 45, Tübingen 72076, Germany; Cognitive Neuroscience of Memory and Consciousness, Institute of Psychology, University of Bern, Fabrikstrasse 8, 3012 Bern, Switzerland.
| | - Flavio Jean Schmidig
- Cognitive Neuroscience of Memory and Consciousness, Institute of Psychology, University of Bern, Fabrikstrasse 8, 3012 Bern, Switzerland
| | - Leona Knüsel
- Cognitive Neuroscience of Memory and Consciousness, Institute of Psychology, University of Bern, Fabrikstrasse 8, 3012 Bern, Switzerland
| | - Katharina Henke
- Cognitive Neuroscience of Memory and Consciousness, Institute of Psychology, University of Bern, Fabrikstrasse 8, 3012 Bern, Switzerland
| |
Collapse
|
13
|
Khodagholy D, Ferrero JJ, Park J, Zhao Z, Gelinas JN. Large-scale, closed-loop interrogation of neural circuits underlying cognition. Trends Neurosci 2022; 45:968-983. [PMID: 36404457 PMCID: PMC10437206 DOI: 10.1016/j.tins.2022.10.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 09/26/2022] [Accepted: 10/03/2022] [Indexed: 11/05/2022]
Abstract
Cognitive functions are increasingly understood to involve coordinated activity patterns between multiple brain regions, and their disruption by neuropsychiatric disorders is similarly complex. Closed-loop neurostimulation can directly modulate neural signals with temporal and spatial precision. How to leverage such an approach to effectively identify and target distributed neural networks implicated in mediating cognition remains unclear. We review current conceptual and technical advances in this area, proposing that devices that enable large-scale acquisition, integrated processing, and multiregion, arbitrary waveform stimulation will be critical for mechanistically driven manipulation of cognitive processes in physiological and pathological brain networks.
Collapse
Affiliation(s)
- Dion Khodagholy
- Department of Electrical Engineering, Columbia University, New York, NY 10027, USA.
| | - Jose J Ferrero
- Institute for Genomic Medicine, Columbia University Irving Medical Center, 701 W 168(th) St., New York, NY 10032, USA
| | - Jaehyo Park
- Department of Electrical Engineering, Columbia University, New York, NY 10027, USA
| | - Zifang Zhao
- Department of Electrical Engineering, Columbia University, New York, NY 10027, USA; Institute for Genomic Medicine, Columbia University Irving Medical Center, 701 W 168(th) St., New York, NY 10032, USA
| | - Jennifer N Gelinas
- Institute for Genomic Medicine, Columbia University Irving Medical Center, 701 W 168(th) St., New York, NY 10032, USA; Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA..
| |
Collapse
|
14
|
Koo-Poeggel P, Neuwerk S, Petersen E, Grasshoff J, Mölle M, Martinetz T, Marshall L. Closed-loop acoustic stimulation during an afternoon nap to modulate subsequent encoding. J Sleep Res 2022; 31:e13734. [PMID: 36123957 DOI: 10.1111/jsr.13734] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 08/31/2022] [Accepted: 09/02/2022] [Indexed: 11/27/2022]
Abstract
Sleep is able to contribute not only to memory consolidation, but also to post-sleep learning. The notion exists that either synaptic downscaling or another process during sleep increase post-sleep learning capacity. A correlation between augmentation of the sleep slow oscillation and hippocampal activation at encoding support the contribution of sleep to encoding of declarative memories. In the present study, the effect of closed-loop acoustic stimulation during an afternoon nap on post-sleep encoding of two verbal (word pairs, verbal learning and memory test) and non-verbal (figural pairs) tasks and on electroencephalogram during sleep and learning were investigated in young healthy adults (N = 16). Closed-loop acoustic stimulation enhanced slow oscillatory and spindle activity, but did not affect encoding at the group level. Subgroup analyses and comparisons with similar studies lead us to the tentative conclusion that further parameters such as time of day and subjects' cognitive ability influenced responses to closed-loop acoustic stimulation.
Collapse
Affiliation(s)
- Ping Koo-Poeggel
- Center of Brain, Behavior and Metabolism, University of Luebeck, Luebeck, Germany.,Institute for Experimental and Clinical Pharmacology and Toxicology, University of Luebeck, Luebeck, Germany
| | - Soé Neuwerk
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Luebeck, Luebeck, Germany
| | - Eike Petersen
- Institute for Electrical and Engineering in Medicine, University of Luebeck, Luebeck, Germany.,DTU Compute, Technical University of Denmark, Denmark
| | - Jan Grasshoff
- Fraunhofer IMTE, Fraunhofer Research Institution for Individualized and Cell-Based Medical Engineering, Lübeck, Germany
| | - Matthias Mölle
- Center of Brain, Behavior and Metabolism, University of Luebeck, Luebeck, Germany
| | - Thomas Martinetz
- Institute for Neuro- and Bioinformatics, University of Luebeck, Luebeck, Germany
| | - Lisa Marshall
- Center of Brain, Behavior and Metabolism, University of Luebeck, Luebeck, Germany.,Institute for Experimental and Clinical Pharmacology and Toxicology, University of Luebeck, Luebeck, Germany
| |
Collapse
|
15
|
Abstract
Over the past few decades, the importance of sleep has become increasingly recognized for many physiologic functions, including cognition. Many studies have reported the deleterious effect of sleep loss or sleep disruption on cognitive performance. Beyond ensuring adequate sleep quality and duration, discovering methods to enhance sleep to augment its restorative effects is important to improve learning in many populations, such as the military, students, age-related cognitive decline, and cognitive disorders.
Collapse
Affiliation(s)
- Roneil G Malkani
- Division of Sleep Medicine, Department of Neurology, Center for Circadian and Sleep Medicine, Northwestern University Feinberg School of Medicine, 710 North Lake Shore Drive, Suite 525, Chicago, IL 60611, USA; Jesse Brown Veterans Affairs Medical Center, Chicago, IL 60612, USA.
| | - Phyllis C Zee
- Division of Sleep Medicine, Department of Neurology, Center for Circadian and Sleep Medicine, Northwestern University Feinberg School of Medicine, 710 North Lake Shore Drive, Suite 520, Chicago, IL 60611, USA
| |
Collapse
|
16
|
Weinhold SL, Lechinger J, Timm N, Hansen A, Ngo HVV, Göder R. Auditory stimulation in-phase with slow oscillations to enhance overnight memory consolidation in patients with schizophrenia? J Sleep Res 2022; 31:e13636. [PMID: 35686351 DOI: 10.1111/jsr.13636] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 03/24/2022] [Accepted: 04/27/2022] [Indexed: 11/27/2022]
Abstract
Sleep-dependent memory consolidation is disturbed in patients with schizophrenia, who furthermore show reductions in sleep spindles and probably also in delta power during sleep. The memory dysfunction in these patients is one of the strongest markers for worse long-term functional outcome. However, therapeutic interventions to normalise memory functions, e.g., with medication, still do not exist. Against this backdrop, we investigated to what extent a non-invasive approach enhancing sleep with real-time auditory stimulation in-phase with slow oscillations might affect overnight memory consolidation in patients with schizophrenia. To this end, we examined 18 patients with stably medicated schizophrenia in a double-blinded sham-controlled design. Memory performance was assessed by a verbal (word list) and a non-verbal (complex figure) declarative memory task. In comparison to a sham condition without auditory stimuli, we found that in patients with schizophrenia, auditory stimulation evokes an electrophysiological response similar to that in healthy participants leading to an increase in slow wave and temporally coupled sleep spindle activity during stimulation. Despite this finding, patients did not show any beneficial effect on the overnight change in memory performance by stimulation. Although the stimulation in our study did not improve the patient's memory, the electrophysiological response gives hope that auditory stimulation could enable us to provide better treatment for sleep-related detriments in these patients in the future.
Collapse
Affiliation(s)
- Sara Lena Weinhold
- Department of Psychiatry and Psychotherapy (ZIP), University Hospital Schleswig-Holstein (UKSH), Kiel, Germany
| | - Julia Lechinger
- Department of Psychiatry and Psychotherapy (ZIP), University Hospital Schleswig-Holstein (UKSH), Kiel, Germany
| | - Nele Timm
- Department of Psychiatry and Psychotherapy (ZIP), University Hospital Schleswig-Holstein (UKSH), Kiel, Germany
| | - Anja Hansen
- Department of Psychiatry and Psychotherapy (ZIP), University Hospital Schleswig-Holstein (UKSH), Kiel, Germany
| | - Hong-Viet V Ngo
- Department of Psychology, University of Lübeck, Lübeck, Germany
| | - Robert Göder
- Department of Psychiatry and Psychotherapy (ZIP), University Hospital Schleswig-Holstein (UKSH), Kiel, Germany
| |
Collapse
|
17
|
Hoedlmoser K, Peigneux P, Rauchs G. Recent advances in memory consolidation and information processing during sleep. J Sleep Res 2022; 31:e13607. [DOI: 10.1111/jsr.13607] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 03/25/2022] [Accepted: 03/25/2022] [Indexed: 12/20/2022]
Affiliation(s)
- Kerstin Hoedlmoser
- Department of Psychology, Centre for Cognitive Neuroscience (CCNS), Laboratory for “Sleep, Cognition and Consciousness Research” University of Salzburg Salzburg Austria
| | - Philippe Peigneux
- UR2NF – Neuropsychology and Functional Neuroimaging Research Unit affiliated at CRCN – Centre for Research in Cognition and Neurosciences and UNI – ULB Neuroscience Institute Bruxelles Belgium
| | - Géraldine Rauchs
- UNICAEN, INSERM, U1237, PhIND “Physiopathology and Imaging of Neurological Disorders”, Institut Blood and Brain @ Caen‐Normandie Normandie Univ Caen France
| |
Collapse
|
18
|
Lustenberger C, Ferster ML, Huwiler S, Brogli L, Werth E, Huber R, Karlen W. Auditory deep sleep stimulation in older adults at home: a randomized crossover trial. COMMUNICATIONS MEDICINE 2022; 2:30. [PMID: 35603302 PMCID: PMC9053232 DOI: 10.1038/s43856-022-00096-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 03/07/2022] [Indexed: 11/13/2022] Open
Abstract
Background Auditory stimulation has emerged as a promising tool to enhance non-invasively sleep slow waves, deep sleep brain oscillations that are tightly linked to sleep restoration and are diminished with age. While auditory stimulation showed a beneficial effect in lab-based studies, it remains unclear whether this stimulation approach could translate to real-life settings. Methods We present a fully remote, randomized, cross-over trial in healthy adults aged 62-78 years (clinicaltrials.gov: NCT03420677). We assessed slow wave activity as the primary outcome and sleep architecture and daily functions, e.g., vigilance and mood as secondary outcomes, after a two-week mobile auditory slow wave stimulation period and a two-week Sham period, interleaved with a two-week washout period. Participants were randomized in terms of which intervention condition will take place first using a blocked design to guarantee balance. Participants and experimenters performing the assessments were blinded to the condition. Results Out of 33 enrolled and screened participants, we report data of 16 participants that received identical intervention. We demonstrate a robust and significant enhancement of slow wave activity on the group-level based on two different auditory stimulation approaches with minor effects on sleep architecture and daily functions. We further highlight the existence of pronounced inter- and intra-individual differences in the slow wave response to auditory stimulation and establish predictions thereof. Conclusions While slow wave enhancement in healthy older adults is possible in fully remote settings, pronounced inter-individual differences in the response to auditory stimulation exist. Novel personalization solutions are needed to address these differences and our findings will guide future designs to effectively deliver auditory sleep stimulations using wearable technology.
Collapse
Affiliation(s)
- Caroline Lustenberger
- Neural Control of Movement Lab, Institute of Human Movement Sciences and Sport, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
- Neuroscience Center Zurich (ZNZ), University of Zurich and ETH Zurich, Zurich, Switzerland
- Center of Competence Sleep & Health Zurich, University of Zurich, Zurich, Switzerland
| | - M. Laura Ferster
- Mobile Health Systems Lab, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Stephanie Huwiler
- Neural Control of Movement Lab, Institute of Human Movement Sciences and Sport, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Luzius Brogli
- Mobile Health Systems Lab, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
- Institute of Biomedical Engineering, Universität Ulm, Ulm, Germany
| | - Esther Werth
- Neuroscience Center Zurich (ZNZ), University of Zurich and ETH Zurich, Zurich, Switzerland
- Center of Competence Sleep & Health Zurich, University of Zurich, Zurich, Switzerland
- Department of Neurology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Reto Huber
- Neuroscience Center Zurich (ZNZ), University of Zurich and ETH Zurich, Zurich, Switzerland
- Center of Competence Sleep & Health Zurich, University of Zurich, Zurich, Switzerland
- Child Development Centre, University Children’s Hospital, University of Zurich, Zurich, Switzerland
- Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Walter Karlen
- Center of Competence Sleep & Health Zurich, University of Zurich, Zurich, Switzerland
- Mobile Health Systems Lab, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
- Institute of Biomedical Engineering, Universität Ulm, Ulm, Germany
| |
Collapse
|
19
|
Choi J, Jun SC. Spindle-targeted acoustic stimulation may stabilize an ongoing nap. J Sleep Res 2022; 31:e13583. [PMID: 35289006 DOI: 10.1111/jsr.13583] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 02/17/2022] [Accepted: 02/25/2022] [Indexed: 11/28/2022]
Abstract
There have been numerous attempts over the decades to introduce closed-loop feedback to induce sleep oscillations. Recently, our group also introduced closed-loop acoustic feedback to the sleep spindle and reported improved procedural memory consolidation during a nap with spindle-targeted pink noise stimulation. In this study, we replicated our previous work with a control condition in an attempt to investigate the effect of closed-loop feedback on procedural memory. The results demonstrated a significant improvement in the subjects' procedural learning and reduced wake time during the nap with closed-loop acoustic stimulation compared with the control condition. Further, we found that randomized acoustic stimuli lead to more frequent spindle activity and a faster decrement in slow oscillation power compared with the sham condition. There were strong correlations between slow oscillation and measures related to sleep efficiency as well. Interestingly, we found a marginal enhancement in procedural learning during the nap with the closed-loop acoustic stimulation compared with the sham nap. We also found a marginal decrement in theta power during the nap with closed-loop feedback compared with the sham nap, and a negative correlation between slow oscillation and theta power. We speculate that the marginal improvement in procedural learning may be related to closed-loop acoustic feedback's stabilization of non-rapid eye movement sleep. Taken together, this study shows that the closed-loop feedback method has the potential to stabilize sleep and improve procedural memory.
Collapse
Affiliation(s)
- Jinyoung Choi
- School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, Gwangju, South Korea
| | - Sung Chan Jun
- School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, Gwangju, South Korea
| |
Collapse
|
20
|
Navarrete M, Arthur S, Treder MS, Lewis PA. Ongoing neural oscillations predict the post-stimulus outcome of closed loop auditory stimulation during slow-wave sleep. Neuroimage 2022; 253:119055. [PMID: 35276365 DOI: 10.1016/j.neuroimage.2022.119055] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 02/26/2022] [Accepted: 03/01/2022] [Indexed: 10/18/2022] Open
Abstract
Large slow oscillations (SO, 0.5-2 Hz) characterise slow-wave sleep and are crucial to memory consolidation and other physiological functions. Manipulating slow oscillations may enhance sleep and memory, as well as benefitting the immune system. Closed-loop auditory stimulation (CLAS) has been demonstrated to increase the SO amplitude and to boost fast sleep spindle activity (11-16 Hz). Nevertheless, not all such stimuli are effective in evoking SOs, even when they are precisely phase locked. Here, we studied what factors of the ongoing activity patterns may help to determine what oscillations to stimulate to effectively enhance SOs or SO-locked spindle activity. Hence, we trained classifiers using the morphological characteristics of the ongoing SO, as measured by electroencephalography (EEG), to predict whether stimulation would lead to a benefit in terms of the resulting SO and spindle amplitude. Separate classifiers were trained using trials from spontaneous control and stimulated datasets, and we evaluated their performance by applying them to held-out data both within and across conditions. We were able to predict both when large SOs occurred spontaneously, and whether a phase-locked auditory click effectively enlarged them with good accuracy for predicting the SO trough (∼70%) and SO peak values (∼80%). Also, we were able to predict when stimulation would elicit spindle activity with an accuracy of ∼60%. Finally, we evaluate the importance of the various SO features used to make these predictions. Our results offer new insight into SO and spindle dynamics and may suggest techniques for developing future methods for online optimization of stimulation.
Collapse
Affiliation(s)
- Miguel Navarrete
- Cardiff University Brain Research Imaging Center (CUBRIC), School of Psychology, Cardiff University, Maindy Rd, Cardiff CF24 4HQ, UK.
| | - Steven Arthur
- School of Computer Science and Informatics, Cardiff University, Queen's Buildings, 5 The Parade, Roath, Cardiff CF24 3AA, UK
| | - Matthias S Treder
- School of Computer Science and Informatics, Cardiff University, Queen's Buildings, 5 The Parade, Roath, Cardiff CF24 3AA, UK
| | - Penelope A Lewis
- Cardiff University Brain Research Imaging Center (CUBRIC), School of Psychology, Cardiff University, Maindy Rd, Cardiff CF24 4HQ, UK.
| |
Collapse
|
21
|
Henao D, Navarrete M, Juez JY, Dinh H, Gómez R, Valderrama M, Le Van Quyen M. Auditory closed‐loop stimulation on sleep slow oscillations using in‐ear EEG sensors. J Sleep Res 2022; 31:e13555. [DOI: 10.1111/jsr.13555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 01/14/2022] [Accepted: 01/17/2022] [Indexed: 11/30/2022]
Affiliation(s)
- David Henao
- Department of Biomedical Engineering Universidad de Los Andes Bogotá D.C. Colombia
| | - Miguel Navarrete
- Department of Biomedical Engineering Universidad de Los Andes Bogotá D.C. Colombia
- Cardiff University Brain Research Imaging Centre (CUBRIC) School of Psychology Cardiff University Cardiff UK
| | - José Yesith Juez
- Department of Biomedical Engineering Universidad de Los Andes Bogotá D.C. Colombia
| | | | - Rodrigo Gómez
- Department of Biomedical Engineering Universidad de Los Andes Bogotá D.C. Colombia
| | - Mario Valderrama
- Department of Biomedical Engineering Universidad de Los Andes Bogotá D.C. Colombia
| | - Michel Le Van Quyen
- Laboratoire d’Imagerie Biomédicale (LIB) Inserm U1146/Sorbonne Université UMCR2/UMR7371 CNRS Paris France
| |
Collapse
|
22
|
Stanyer EC, Baniqued PDE, Awais M, Kouara L, Davies AG, Killan EC, Mushtaq F. The impact of acoustic stimulation during sleep on memory and sleep architecture: A meta-analysis. J Sleep Res 2021; 31:e13385. [PMID: 34850995 DOI: 10.1111/jsr.13385] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 04/12/2021] [Accepted: 04/19/2021] [Indexed: 11/28/2022]
Abstract
The relationship between sleep and cognition has long been recognized, with slow-wave sleep thought to play a critical role in long-term memory consolidation. Recent research has presented the possibility that non-invasive acoustic stimulation during sleep could enhance memory consolidation. Herein, we report a random-effects model meta-analysis examining the impact of this intervention on memory and sleep architecture in healthy adults. Sixteen studies were identified through a systematic search. We found a medium significant effect of acoustic stimulation on memory task performance (g = 0.68, p = .031) in young adults <35 years of age, but no statistically significant effect in adults >35 years of age (g = -0.83, p = .223). In young adults, there was a large statistically significant effect for declarative memory tasks (g = 0.87, p = .014) but no effect for non-declarative tasks (g = -0.25, p = .357). There were no statistically significant differences in polysomnography-derived sleep architecture values between sham and stimulation conditions in either young or older adults. Based on these results, it appears that acoustic stimulation during sleep may only be an effective intervention for declarative memory consolidation in young adults. However, the small number of studies in this area, their small sample sizes, the short-term nature of most investigations and the high between-studies heterogeneity highlight a need for high-powered and long-term experiments to better elucidate, and subsequently maximise, any potential benefits of this novel approach.
Collapse
Affiliation(s)
- Emily C Stanyer
- School of Psychology, Faculty of Medicine and Health, University of Leeds, Leeds, West Yorkshire, UK.,Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Paul Dominick E Baniqued
- School of Psychology, Faculty of Medicine and Health, University of Leeds, Leeds, West Yorkshire, UK.,School of Mechanical Engineering, Faculty of Engineering and Physical Sciences, University of Leeds, Leeds, West Yorkshire, UK
| | - Muhammad Awais
- School of Psychology, Faculty of Medicine and Health, University of Leeds, Leeds, West Yorkshire, UK.,Department of Computer Science, Edgehill University, Ormskirk, Lancashire, UK
| | - Layla Kouara
- School of Psychology, Faculty of Medicine and Health, University of Leeds, Leeds, West Yorkshire, UK
| | - Andrew G Davies
- Leeds Institute of Cardiovascular and Metabolic Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, West Yorkshire, UK
| | - Edward C Killan
- Leeds Institute of Cardiovascular and Metabolic Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, West Yorkshire, UK
| | - Faisal Mushtaq
- School of Psychology, Faculty of Medicine and Health, University of Leeds, Leeds, West Yorkshire, UK
| |
Collapse
|
23
|
Liu X, Richardson AG. A System-on-Chip for Closed-loop Optogenetic Sleep Modulation. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2021; 2021:5678-5681. [PMID: 34892410 DOI: 10.1109/embc46164.2021.9629745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Stimulation of target neuronal populations using optogenetic techniques during specific sleep stages has begun to elucidate the mechanisms and effects of sleep. To conduct closed-loop optogenetic sleep studies in untethered animals, we designed a fully integrated, low-power system-on-chip (SoC) for real-time sleep stage classification and stage-specific optical stimulation. The SoC consists of a 4-channel analog front-end for recording polysomnography signals, a mixed-signal machine-learning (ML) core, and a 16-channel optical stimulation back-end. A novel ML algorithm and innovative circuit design techniques improved the online classification performance while minimizing power consumption. The SoC was designed and simulated in 180 nm CMOS technology. In an evaluation using an expert labeled sleep database with 20 subjects, the SoC achieves a high sensitivity of 0.806 and a specificity of 0.947 in discriminating 5 sleep stages. Overall power consumption in continuous operation is 97 µW.
Collapse
|
24
|
Moreira CG, Baumann CR, Scandella M, Nemirovsky SI, Leach S, Huber R, Noain D. Closed-loop auditory stimulation method to modulate sleep slow waves and motor learning performance in rats. eLife 2021; 10:e68043. [PMID: 34612204 PMCID: PMC8530509 DOI: 10.7554/elife.68043] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 09/29/2021] [Indexed: 12/26/2022] Open
Abstract
Slow waves and cognitive output have been modulated in humans by phase-targeted auditory stimulation. However, to advance its technical development and further our understanding, implementation of the method in animal models is indispensable. Here, we report the successful employment of slow waves' phase-targeted closed-loop auditory stimulation (CLAS) in rats. To validate this new tool both conceptually and functionally, we tested the effects of up- and down-phase CLAS on proportions and spectral characteristics of sleep, and on learning performance in the single-pellet reaching task, respectively. Without affecting 24 hr sleep-wake behavior, CLAS specifically altered delta (slow waves) and sigma (sleep spindles) power persistently over chronic periods of stimulation. While up-phase CLAS does not elicit a significant change in behavioral performance, down-phase CLAS exerted a detrimental effect on overall engagement and success rate in the behavioral test. Overall CLAS-dependent spectral changes were positively correlated with learning performance. Altogether, our results provide proof-of-principle evidence that phase-targeted CLAS of slow waves in rodents is efficient, safe, and stable over chronic experimental periods, enabling the use of this high-specificity tool for basic and preclinical translational sleep research.
Collapse
Affiliation(s)
- Carlos G Moreira
- Department of Neurology, University Hospital Zurich, University of ZurichZurichSwitzerland
| | - Christian R Baumann
- Department of Neurology, University Hospital Zurich, University of ZurichZurichSwitzerland
- University Center of Competence Sleep & Health Zurich (CRPP), University of ZurichZurichSwitzerland
- Neuroscience Center Zurich (ZNZ)ZurichSwitzerland
| | - Maurizio Scandella
- Department of Neurology, University Hospital Zurich, University of ZurichZurichSwitzerland
| | - Sergio I Nemirovsky
- Institute of Biological Chemistry, School of Exact and Natural Sciences (IQUIBICEN). CONICET – University of Buenos AiresBuenos AiresArgentina
| | - Sven Leach
- Child Development Center, University Children’s Hospital Zurich, University of ZurichZurichSwitzerland
| | - Reto Huber
- University Center of Competence Sleep & Health Zurich (CRPP), University of ZurichZurichSwitzerland
- Neuroscience Center Zurich (ZNZ)ZurichSwitzerland
- Child Development Center, University Children’s Hospital Zurich, University of ZurichZurichSwitzerland
- Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital, University of ZurichZurichSwitzerland
| | - Daniela Noain
- Department of Neurology, University Hospital Zurich, University of ZurichZurichSwitzerland
- University Center of Competence Sleep & Health Zurich (CRPP), University of ZurichZurichSwitzerland
- Neuroscience Center Zurich (ZNZ)ZurichSwitzerland
| |
Collapse
|
25
|
Wunderlin M, Züst MA, Hertenstein E, Fehér KD, Schneider CL, Klöppel S, Nissen C. Modulating overnight memory consolidation by acoustic stimulation during slow-wave sleep: a systematic review and meta-analysis. Sleep 2021; 44:6066545. [PMID: 33406249 DOI: 10.1093/sleep/zsaa296] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/12/2020] [Indexed: 12/18/2022] Open
Abstract
STUDY OBJECTIVES The low-frequency high-amplitude oscillations of slow-wave sleep (SWS) are considered to promote the consolidation of episodic memory. Previous research suggests that sleep slow waves can be entrained and enhanced by presenting short acoustic stimuli to the up-states of endogenous waves. Several studies have investigated the effects of these increases in slow-wave activity on overnight memory consolidation, with inconsistent results. The aim of this meta-analysis was to evaluate the accumulated evidence connecting acoustic stimulation during sleep to episodic memory consolidation. METHODS A systematic literature search was conducted in October 2020 using PubMed, Web of Science, and PsycInfo. The main study inclusion criteria were the application of acoustic slow wave enhancement in healthy participants and an assessment of pre- and post-sleep episodic memory performance. Effect sizes were pooled using a random-effects model. RESULTS A total of 10 primary studies with 11 experiments and 177 participants were included. Results showed a combined effect size (Hedges' g) of 0.25 (p = 0.07). Subgroup models based on young adults (n = 8), phase-locked stimulation approaches (n = 8), and their combination (n = 6) showed combined effect sizes of 0.31 (p = 0.051), 0.36 (p = 0.047), and 0.44 (p = 0.01), respectively. There was no indication of publication bias or bias in individual studies. CONCLUSIONS Acoustic enhancement of SWS tends to increase the overnight consolidation of episodic memory but effects remain small and-with the exception of subgroup models-at trend levels. Currently, the evidence is not sufficient to recommend the use of commercially available devices.
Collapse
Affiliation(s)
- Marina Wunderlin
- 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
| | - Elisabeth Hertenstein
- University Hospital of Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland
| | - Kristoffer D Fehér
- University Hospital of Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland
| | - Carlotta L Schneider
- University Hospital of Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland
| | - Stefan Klöppel
- 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
| |
Collapse
|
26
|
Harrington MO, Cairney SA. Sounding It Out: Auditory Stimulation and Overnight Memory Processing. CURRENT SLEEP MEDICINE REPORTS 2021; 7:112-119. [PMID: 34722123 PMCID: PMC8550047 DOI: 10.1007/s40675-021-00207-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/29/2021] [Indexed: 02/05/2023]
Abstract
Abstract
Purpose of Review
Auditory stimulation is a technique that can enhance neural oscillations linked to overnight memory consolidation. In this review, we evaluate the impacts of auditory stimulation on the neural oscillations of sleep and associated memory processes in a variety of populations.
Recent Findings
Cortical EEG recordings of slow-wave sleep (SWS) are characterised by two cardinal oscillations: slow oscillations (SOs) and sleep spindles. Auditory stimulation delivered in SWS enhances SOs and phase-coupled spindle activity in healthy children and adults, children with ADHD, adults with mild cognitive impairment and patients with major depression. Under certain conditions, auditory stimulation bolsters the benefits of SWS for memory consolidation, although further work is required to fully understand the factors affecting stimulation-related memory gains. Recent work has turned to rapid eye movement (REM) sleep, demonstrating that auditory stimulation can be used to manipulate REM sleep theta oscillations.
Summary
Auditory stimulation enhances oscillations linked to overnight memory processing and shows promise as a technique for enhancing the memory benefits of sleep.
Collapse
|
27
|
Affiliation(s)
- Simon Ruch
- Institute for Neuromodulation and Neurotechnology, Department of Neurosurgery and Neurotechnology, University Hospital and University of Tuebingen, Germany
| | - Michael Valiadis
- Institute for Neuromodulation and Neurotechnology, Department of Neurosurgery and Neurotechnology, University Hospital and University of Tuebingen, Germany
| | - Alireza Gharabaghi
- Institute for Neuromodulation and Neurotechnology, Department of Neurosurgery and Neurotechnology, University Hospital and University of Tuebingen, Germany
| |
Collapse
|
28
|
Torres FA, Orio P, Escobar MJ. Selection of stimulus parameters for enhancing slow wave sleep events with a neural-field theory thalamocortical model. PLoS Comput Biol 2021; 17:e1008758. [PMID: 34329289 PMCID: PMC8357165 DOI: 10.1371/journal.pcbi.1008758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 08/11/2021] [Accepted: 05/28/2021] [Indexed: 11/30/2022] Open
Abstract
Slow-wave sleep cortical brain activity, conformed by slow-oscillations and sleep spindles, plays a key role in memory consolidation. The increase of the power of the slow-wave events, obtained by auditory sensory stimulation, positively correlates with memory consolidation performance. However, little is known about the experimental protocol maximizing this effect, which could be induced by the power of slow-oscillation, the number of sleep spindles, or the timing of both events' co-occurrence. Using a mean-field model of thalamocortical activity, we studied the effect of several stimulation protocols, varying the pulse shape, duration, amplitude, and frequency, as well as a target-phase using a closed-loop approach. We evaluated the effect of these parameters on slow-oscillations (SO) and sleep-spindles (SP), considering: (i) the power at the frequency bands of interest, (ii) the number of SO and SP, (iii) co-occurrences between SO and SP, and (iv) synchronization of SP with the up-peak of the SO. The first three targets are maximized using a decreasing ramp pulse with a pulse duration of 50 ms. Also, we observed a reduction in the number of SO when increasing the stimulus energy by rising its amplitude. To assess the target-phase parameter, we applied closed-loop stimulation at 0°, 45°, and 90° of the phase of the narrow-band filtered ongoing activity, at 0.85 Hz as central frequency. The 0° stimulation produces better results in the power and number of SO and SP than the rhythmic or random stimulation. On the other hand, stimulating at 45° or 90° change the timing distribution of spindles centers but with fewer co-occurrences than rhythmic and 0° phase. Finally, we propose the application of closed-loop stimulation at the rising zero-cross point using pulses with a decreasing ramp shape and 50 ms of duration for future experimental work.
Collapse
Affiliation(s)
- Felipe A. Torres
- Department of Electronic Engineering, Universidad Técnica Federico Santa María, Valparaíso, Chile
- Advanced Center for Electrical and Electronic Engineering (AC3E), Valparaíso, Chile
| | - Patricio Orio
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile
- Advanced Center for Electrical and Electronic Engineering (AC3E), Valparaíso, Chile
| | - María-José Escobar
- Department of Electronic Engineering, Universidad Técnica Federico Santa María, Valparaíso, Chile
| |
Collapse
|
29
|
No benefit of auditory closed-loop stimulation on memory for semantically-incongruent associations. Neurobiol Learn Mem 2021; 183:107482. [PMID: 34182134 DOI: 10.1016/j.nlm.2021.107482] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/27/2021] [Accepted: 06/22/2021] [Indexed: 02/03/2023]
Abstract
Auditory closed-loop stimulation has gained traction in recent years as a means of enhancing slow oscillatory activity and, consequently, sleep-associated memory consolidation. Previous studies on this topic have primarily focused on the consolidation of semantically-congruent associations. In this study, we investigated the effect of auditory closed-loop stimulation on the overnight retention of semantically-incongruent associations. Twelve healthy males (age: M = 20.06, SD = 2.02 years) participated in two experimental conditions (simulation and sham). In the stimulation condition, clicks were delivered in phase with slow oscillation up-states, whereas in the sham condition no auditory stimuli were applied. Corroborating earlier work, stimulation (vs. sham) enhanced the slow oscillation rhythm, phase-coupled spindle activity and slow oscillation power. However, there was no benefit of stimulation on overnight memory retention. These findings suggest that closed-loop stimulation does not benefit semantically-incongruent associations.
Collapse
|
30
|
Dehnavi F, Koo-Poeggel PC, Ghorbani M, Marshall L. Spontaneous slow oscillation - slow spindle features predict induced overnight memory retention. Sleep 2021; 44:6277833. [PMID: 34003291 PMCID: PMC8503833 DOI: 10.1093/sleep/zsab127] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 05/06/2021] [Indexed: 11/13/2022] Open
Abstract
Study Objectives Synchronization of neural activity within local networks and between brain regions is a major contributor to rhythmic field potentials such as the EEG. On the other hand, dynamic changes in microstructure and activity are reflected in the EEG, for instance slow oscillation (SO) slope can reflect synaptic strength. SO-spindle coupling is a measure for neural communication. It was previously associated with memory consolidation, but also shown to reveal strong interindividual differences. In studies, weak electric current stimulation has modulated brain rhythms and memory retention. Here, we investigate whether SO-spindle coupling and SO slope during baseline sleep are associated with (predictive of) stimulation efficacy on retention performance. Methods Twenty-five healthy subjects participated in three experimental sessions. Sleep-associated memory consolidation was measured in two sessions, in one anodal transcranial direct current stimulation oscillating at subjects individual SO frequency (so-tDCS) was applied during nocturnal sleep. The third session was without a learning task (baseline sleep). The dependence on SO-spindle coupling and SO-slope during baseline sleep of so-tDCS efficacy on retention performance were investigated. Results Stimulation efficacy on overnight retention of declarative memories was associated with nesting of slow spindles to SO trough in deep nonrapid eye movement baseline sleep. Steepness and direction of SO slope in baseline sleep were features indicative for stimulation efficacy. Conclusions Findings underscore a functional relevance of activity during the SO up-to-down state transition for memory consolidation and provide support for distinct consolidation mechanisms for types of declarative memories.
Collapse
Affiliation(s)
- Fereshteh Dehnavi
- Department of Electrical Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Ping Chai Koo-Poeggel
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Ratzeburger Allee, Lübeck, Germany.,Center of Brain, Behavior and Metabolism, University of Lübeck, Lübeck
| | - Maryam Ghorbani
- Department of Electrical Engineering, Ferdowsi University of Mashhad, Mashhad, Iran.,Rayan Center for Neuroscience and Behavior, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Lisa Marshall
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Ratzeburger Allee, Lübeck, Germany.,Center of Brain, Behavior and Metabolism, University of Lübeck, Lübeck
| |
Collapse
|
31
|
Harrington MO, Ashton JE, Ngo HVV, Cairney SA. Phase-locked auditory stimulation of theta oscillations during rapid eye movement sleep. Sleep 2021; 44:5960115. [PMID: 33159523 DOI: 10.1093/sleep/zsaa227] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 09/24/2020] [Indexed: 12/15/2022] Open
Abstract
Auditory closed-loop stimulation is a non-invasive technique that has been widely used to augment slow oscillations during non-rapid eye movement sleep. Based on the principles of closed-loop stimulation, we developed a novel protocol for manipulating theta activity (3-7 Hz) in rapid eye movement (REM) sleep. Sixteen healthy young adults were studied in two overnight conditions: Stimulation and Sham. In the Stimulation condition, 1 s of 5 Hz amplitude-modulated white noise was delivered upon detection of two supra-threshold theta cycles throughout REM sleep. In the Sham condition, corresponding time points were marked but no stimulation was delivered. Auditory stimulation entrained EEG activity to 5 Hz and evoked a brief (~0.5 s) increase in theta power. Interestingly, this initial theta surge was immediately followed by a prolonged (~3 s) period of theta suppression. Stimulation also induced a prolonged (~2 s) increase in beta power. Our results provide the first demonstration that the REM sleep theta rhythm can be manipulated in a targeted manner via auditory stimulation. Accordingly, auditory stimulation might offer a fruitful avenue for investigating REM sleep electrophysiology and its relationship to behavior.
Collapse
Affiliation(s)
| | | | - Hong-Viet V Ngo
- Donders Institute for Brain, Cognition and Behaviour, Radboudumc, The Netherlands.,Department of Psychology, University of Lübeck, Lübeck, Germany
| | - Scott A Cairney
- Department of Psychology, University of York, Heslington, York, UK.,York Biomedical Research Institute (YBRI), University of York, Heslington, York, UK
| |
Collapse
|
32
|
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.
Collapse
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:
| |
Collapse
|
33
|
Fehér KD, Wunderlin M, Maier JG, Hertenstein E, Schneider CL, Mikutta C, Züst MA, Klöppel S, Nissen C. Shaping the slow waves of sleep: A systematic and integrative review of sleep slow wave modulation in humans using non-invasive brain stimulation. Sleep Med Rev 2021; 58:101438. [PMID: 33582581 DOI: 10.1016/j.smrv.2021.101438] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 10/14/2020] [Accepted: 11/10/2020] [Indexed: 01/19/2023]
Abstract
The experimental study of electroencephalographic slow wave sleep (SWS) stretches over more than half a century and has corroborated its importance for basic physiological processes, such as brain plasticity, metabolism and immune system functioning. Alterations of SWS in aging or pathological conditions suggest that modulating SWS might constitute a window for clinically relevant interventions. This work provides a systematic and integrative review of SWS modulation through non-invasive brain stimulation in humans. A literature search using PubMed, conducted in May 2020, identified 3220 studies, of which 82 fulfilled inclusion criteria. Three approaches have been adopted to modulate the macro- and microstructure of SWS, namely auditory, transcranial electrical and transcranial magnetic stimulation. Our current knowledge about the modulatory mechanisms, the space of stimulation parameters and the physiological and behavioral effects are reported and evaluated. The integration of findings suggests that sleep slow wave modulation bears the potential to promote our understanding of the functions of SWS and to develop new treatments for conditions of disrupted SWS.
Collapse
Affiliation(s)
- Kristoffer D Fehér
- University Hospital of Psychiatry and Psychotherapy, University of Bern, Switzerland
| | - Marina Wunderlin
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, Switzerland
| | - Jonathan G Maier
- University Hospital of Psychiatry and Psychotherapy, University of Bern, Switzerland
| | - Elisabeth Hertenstein
- University Hospital of Psychiatry and Psychotherapy, University of Bern, Switzerland
| | - Carlotta L Schneider
- University Hospital of Psychiatry and Psychotherapy, University of Bern, Switzerland
| | - Christian Mikutta
- University Hospital of Psychiatry and Psychotherapy, University of Bern, Switzerland; Privatklinik Meiringen, Meiringen, Switzerland
| | - Marc A Züst
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, Switzerland
| | - Stefan Klöppel
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, Switzerland
| | - Christoph Nissen
- University Hospital of Psychiatry and Psychotherapy, University of Bern, Switzerland.
| |
Collapse
|
34
|
Voysey ZJ, Barker RA, Lazar AS. The Treatment of Sleep Dysfunction in Neurodegenerative Disorders. Neurotherapeutics 2021; 18:202-216. [PMID: 33179197 PMCID: PMC8116411 DOI: 10.1007/s13311-020-00959-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/22/2020] [Indexed: 12/13/2022] Open
Abstract
Sleep dysfunction is highly prevalent across the spectrum of neurodegenerative conditions and is a key determinant of quality of life for both patients and their families. Mounting recent evidence also suggests that such dysfunction exacerbates cognitive and affective clinical features of neurodegeneration, as well as disease progression through acceleration of pathogenic processes. Effective assessment and treatment of sleep dysfunction in neurodegeneration is therefore of paramount importance; yet robust therapeutic guidelines are lacking, owing in part to a historical paucity of effective treatments and trials. Here, we review the common sleep abnormalities evident in neurodegenerative disease states and evaluate the latest evidence for traditional and emerging interventions, both pharmacological and nonpharmacological. Interventions considered include conservative measures, targeted treatments of specific clinical sleep pathologies, established sedating and alerting agents, melatonin, and orexin antagonists, as well as bright light therapy, behavioral measures, and slow-wave sleep augmentation techniques. We conclude by providing a suggested framework for treatment based on contemporary evidence and highlight areas that may emerge as major therapeutic advances in the near future.
Collapse
Affiliation(s)
- Zanna J Voysey
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, CB2 0PY, UK
| | - Roger A Barker
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair and WT-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, CB2 0PY, UK
| | - Alpar S Lazar
- Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, NR4 7TJ, UK.
| |
Collapse
|
35
|
Harris SS, Schwerd-Kleine T, Lee BI, Busche MA. The Reciprocal Interaction Between Sleep and Alzheimer's Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1344:169-188. [PMID: 34773232 DOI: 10.1007/978-3-030-81147-1_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
It is becoming increasingly recognized that patients with a variety of neurodegenerative diseases exhibit disordered sleep/wake patterns. While sleep impairments have typically been thought of as sequelae of underlying neurodegenerative processes in sleep-wake cycle regulating brain regions, including the brainstem, hypothalamus, and basal forebrain, emerging evidence now indicates that sleep deficits may also act as pathophysiological drivers of brain-wide disease progression. Specifically, recent work has indicated that impaired sleep can impact on neuronal activity, brain clearance mechanisms, pathological build-up of proteins, and inflammation. Altered sleep patterns may therefore be novel (potentially reversible) dynamic functional markers of proteinopathies and modifiable targets for early therapeutic intervention using non-invasive stimulation and behavioral techniques. Here we highlight research describing a potentially reciprocal interaction between impaired sleep and circadian patterns and the accumulation of pathological signs and features in Alzheimer's disease, the most prevalent neurodegenerative disease in the elderly.
Collapse
Affiliation(s)
| | | | - Byung Il Lee
- UK Dementia Research Institute at UCL, London, UK
| | | |
Collapse
|
36
|
Cordi MJ. Updated Review of the Acoustic Modulation of Sleep: Current Perspectives and Emerging Concepts. Nat Sci Sleep 2021; 13:1319-1330. [PMID: 34335067 PMCID: PMC8318210 DOI: 10.2147/nss.s284805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 07/12/2021] [Indexed: 11/23/2022] Open
Abstract
With growing interest in the use of acoustic stimuli in sleep research and acoustic interventions used therapeutically for sleep enhancement, there is a need for an overview of the current lines of research. This paper summarizes the various ways to use acoustic input before sleep or stimulation during sleep. It thereby focuses on the respective methodological requirements, advantages, disadvantages, potentials and difficulties of acoustic sleep modulation. It highlights differences in subjective and objective outcome measures, immediate and whole night effects and short versus long term effects. This recognizes the fact that not all outcome parameters are relevant in every research field. The same applies to conclusions drawn from other outcome dimensions, consideration of mediating factors, levels of stimulation processing and the impact of inter-individual differences. In addition to the deliberate influences of acoustic input on sleep, one paragraph describes adverse environmental acoustic influences. Finally, the possibilities for clinical and basic research-related applications are discussed, and emerging opportunities are presented. This overview is not a systematic review but aims to present the current perspective and hence summarizes the most up-to-date research results and reviews. This is the first review providing a summary of the broad spectrum of possibilities to acoustically influence sleep.
Collapse
Affiliation(s)
- Maren Jasmin Cordi
- Department of Psychology, Division of Cognitive Biopsychology and Methods, University of Fribourg, Fribourg, Switzerland.,Centre of Competence Sleep & Health Zurich, University of Zurich, Zurich, Switzerland
| |
Collapse
|
37
|
Eckert MJ, Iyer K, Euston DR, Tatsuno M. Reliable induction of sleep spindles with intracranial electrical pulse stimulation. ACTA ACUST UNITED AC 2020; 28:7-11. [PMID: 33323496 PMCID: PMC7747649 DOI: 10.1101/lm.052464.120] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 09/27/2020] [Indexed: 01/19/2023]
Abstract
Neocortical sleep spindles have been shown to occur more frequently following a memory task, suggesting that a method to increase spindle activity could improve memory processing. Stimulation of the neocortex can elicit a slow oscillation (SO) and a spindle, but the feasibility of this method to boost SO and spindles over time has not been tested. In rats with implanted neocortical electrodes, stimulation during slow wave sleep significantly increased SO and spindle rates compared to control rest periods before and after the stimulation session. Coordination between hippocampal sharp-wave ripples and spindles also increased. These effects were reproducible across five consecutive days of testing, demonstrating the viability of this method to increase SO and spindles.
Collapse
Affiliation(s)
- Michael J Eckert
- Department of Neuroscience, University of Lethbridge, Lethbridge, Alberta T1K 3M4, Canada
| | - Kartik Iyer
- Department of Neuroscience, University of Lethbridge, Lethbridge, Alberta T1K 3M4, Canada
| | - David R Euston
- Department of Neuroscience, University of Lethbridge, Lethbridge, Alberta T1K 3M4, Canada
| | - Masami Tatsuno
- Department of Neuroscience, University of Lethbridge, Lethbridge, Alberta T1K 3M4, Canada
| |
Collapse
|
38
|
Paller KA, Creery JD, Schechtman E. Memory and Sleep: How Sleep Cognition Can Change the Waking Mind for the Better. Annu Rev Psychol 2020; 72:123-150. [PMID: 32946325 DOI: 10.1146/annurev-psych-010419-050815] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The memories that we retain can serve many functions. They guide our future actions, form a scaffold for constructing the self, and continue to shape both the self and the way we perceive the world. Although most memories we acquire each day are forgotten, those integrated within the structure of multiple prior memories tend to endure. A rapidly growing body of research is steadily elucidating how the consolidation of memories depends on their reactivation during sleep. Processing memories during sleep not only helps counteract their weakening but also supports problem solving, creativity, and emotional regulation. Yet, sleep-based processing might become maladaptive, such as when worries are excessively revisited. Advances in research on memory and sleep can thus shed light on how this processing influences our waking life, which can further inspire the development of novel strategies for decreasing detrimental rumination-like activity during sleep and for promoting beneficial sleep cognition.
Collapse
Affiliation(s)
- Ken A Paller
- Department of Psychology and Cognitive Neuroscience Program, Northwestern University, Evanston, Illinois 60208, USA; , ,
| | - Jessica D Creery
- Department of Psychology and Cognitive Neuroscience Program, Northwestern University, Evanston, Illinois 60208, USA; , ,
| | - Eitan Schechtman
- Department of Psychology and Cognitive Neuroscience Program, Northwestern University, Evanston, Illinois 60208, USA; , ,
| |
Collapse
|
39
|
Cordi MJ, Rasch B. How robust are sleep-mediated memory benefits? Curr Opin Neurobiol 2020; 67:1-7. [PMID: 32711356 DOI: 10.1016/j.conb.2020.06.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 06/17/2020] [Accepted: 06/18/2020] [Indexed: 01/12/2023]
Abstract
Memories benefit from a retention interval filled with sleep. Current theories assume that this beneficial effect relies on consolidation processes occurring during slow-wave sleep (SWS). However, in the last years, several key findings supporting these theories could not be replicated or occurred only under certain conditions, suggesting that effects of sleep on memory are smaller, more task-dependent, less SWS-related, less robust and less long-lasting than previously assumed. In this review, we summarize recent replication failures, null-findings, meta-analyses and studies reporting important boundary conditions for the effect of sleep on declarative memory. We argue that more attempts to replicate and meta-analytic approaches together with higher standards for reproducible science are critical to advance the field of sleep and memory.
Collapse
Affiliation(s)
- Maren Jasmin Cordi
- Department of Psychology, Division of Cognitive Biopsychology and Methods, University of Fribourg, Fribourg, Switzerland
| | - Björn Rasch
- Department of Psychology, Division of Cognitive Biopsychology and Methods, University of Fribourg, Fribourg, Switzerland.
| |
Collapse
|
40
|
Cox R, Fell J. Analyzing human sleep EEG: A methodological primer with code implementation. Sleep Med Rev 2020; 54:101353. [PMID: 32736239 DOI: 10.1016/j.smrv.2020.101353] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 04/30/2020] [Accepted: 04/30/2020] [Indexed: 12/15/2022]
Abstract
Recent years have witnessed a surge in human sleep electroencephalography (EEG) studies, employing increasingly sophisticated analysis strategies to relate electrophysiological activity to cognition and disease. However, properly calculating and interpreting metrics used in contemporary sleep EEG requires attention to numerous theoretical and practical signal-processing details that are not always obvious. Moreover, the vast number of outcome measures that can be derived from a single dataset inflates the risk of false positives and threatens replicability. We review several methodological issues related to 1) spectral analysis, 2) montage choice, 3) extraction of phase and amplitude information, 4) surrogate construction, and 5) minimizing false positives, illustrating both the impact of methodological choices on downstream results, and the importance of checking processing steps through visualization and simplified examples. By presenting these issues in non-mathematical form, with sleep-specific examples, and with code implementation, this paper aims to instill a deeper appreciation of methodological considerations in novice and non-technical audiences, and thereby help improve the quality of future sleep EEG studies.
Collapse
Affiliation(s)
- Roy Cox
- Department of Epileptology, University of Bonn, 53127 Bonn, Germany.
| | - Juergen Fell
- Department of Epileptology, University of Bonn, 53127 Bonn, Germany
| |
Collapse
|
41
|
Krempp C, Paulk AC, Truccolo W, Cash SS, Zelmann R. Effect of Closed-Loop Direct Electrical Stimulation during Sleep Spindles in Humans. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:3586-3589. [PMID: 33018778 DOI: 10.1109/embc44109.2020.9175404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Sleep spindles are transient oscillations in the brain related to sleep consolidation and memory. We investigated if brief, localized electrical pulses could perturb spindles on five human patients with intracerebral electrodes implanted for clinical purpose. We used a closed-loop setup to specifically detect spindles and stimulate in real-time during these events. Stimulation latency was 200-400 ms following spindle onset. Analyzing the intracranial electro-encephalographic (iEEG) data both locally and globally, we found, in two of the patients, that single pulse stimulation could stop the spindles locally. Spindles were shorter than those without stimulation and a decrease in power at the same frequency as spindles was observed following stimulation.Clinical Relevance- This study shows that brief and precise electrical stimulation may be used to modulate oscillatory behavior of the human brain. Applied to sleep spindles, further studies may establish that single pulses applied in a closed-loop manner could be used to modulate memory and could help understand effect of neuromodulation in sleep disruption.
Collapse
|
42
|
A Systematic Review of Closed-Loop Feedback Techniques in Sleep Studies-Related Issues and Future Directions. SENSORS 2020; 20:s20102770. [PMID: 32414060 PMCID: PMC7285770 DOI: 10.3390/s20102770] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/13/2020] [Accepted: 05/10/2020] [Indexed: 01/09/2023]
Abstract
Advances in computer processing technology have enabled researchers to analyze real-time brain activity and build real-time closed-loop paradigms. In many fields, the effectiveness of these closed-loop protocols has proven to be better than that of the simple open-loop paradigms. Recently, sleep studies have attracted much attention as one possible application of closed-loop paradigms. To date, several studies that used closed-loop paradigms have been reported in the sleep-related literature and recommend a closed-loop feedback system to enhance specific brain activity during sleep, which leads to improvements in sleep's effects, such as memory consolidation. However, to the best of our knowledge, no report has reviewed and discussed the detailed technical issues that arise in designing sleep closed-loop paradigms. In this paper, we reviewed the most recent reports on sleep closed-loop paradigms and offered an in-depth discussion of some of their technical issues. We found 148 journal articles strongly related with 'sleep and stimulation' and reviewed 20 articles on closed-loop feedback sleep studies. We focused on human sleep studies conducting any modality of feedback stimulation. Then we introduced the main component of the closed-loop system and summarized several open-source libraries, which are widely used in closed-loop systems, with step-by-step guidelines for closed-loop system implementation for sleep. Further, we proposed future directions for sleep research with closed-loop feedback systems, which provide some insight into closed-loop feedback systems.
Collapse
|