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Chen D, Xia T, Yao Z, Zhang L, Hu X. Modulating social learning-induced evaluation updating during human sleep. NPJ SCIENCE OF LEARNING 2024; 9:43. [PMID: 38971834 PMCID: PMC11227583 DOI: 10.1038/s41539-024-00255-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 06/13/2024] [Indexed: 07/08/2024]
Abstract
People often change their evaluations upon learning about their peers' evaluations, i.e., social learning. Given sleep's vital role in consolidating daytime experiences, sleep may facilitate social learning, thereby further changing people's evaluations. Combining a social learning task and the sleep-based targeted memory reactivation technique, we asked whether social learning-induced evaluation updating can be modulated during sleep. After participants had indicated their initial evaluation of snacks, they learned about their peers' evaluations while hearing the snacks' spoken names. During the post-learning non-rapid-eye-movement sleep, we re-played half of the snack names (i.e., cued snack) to reactivate the associated peers' evaluations. Upon waking up, we found that the social learning-induced evaluation updating further enlarged for both cued and uncued snacks. Examining sleep electroencephalogram (EEG) activity revealed that cue-elicited delta-theta EEG power and the overnight N2 sleep spindle density predicted post-sleep evaluation updating for cued but not for uncued snacks. These findings underscore the role of sleep-mediated memory reactivation and the associated neural activity in supporting social learning-induced evaluation updating.
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Affiliation(s)
- Danni Chen
- Department of Psychology, The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Tao Xia
- Department of Psychology, The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Ziqing Yao
- Department of Psychology, The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Lingqi Zhang
- Department of Psychology, The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Xiaoqing Hu
- Department of Psychology, The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong SAR, China.
- HKU-Shenzhen Institute of Research and Innovation, Shenzhen, China.
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2
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Sifuentes Ortega R, Peigneux P. Does Targeted Memory Reactivation during SWS and REM sleep have differential effects on mnemonic discrimination and generalization? Sleep 2024:zsae114. [PMID: 38766994 DOI: 10.1093/sleep/zsae114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Indexed: 05/22/2024] Open
Abstract
Targeted memory reactivation (TMR), or the presentation of learning-related cues during sleep, has been shown to benefit memory consolidation for specific memory traces when applied during non-rapid eye movement (NREM) sleep. Prior studies suggest that TMR during REM sleep may play a role in memory generalization processes, but evidence remains scarce. We tested the hypothesis that TMR exerts a differential effect on distinct mnemonic processes as a function of the sleep state (REM vs. NREM) in which TMR is delivered. Mnemonic discrimination and generalization of semantic categories were investigated using an adapted version of the Mnemonic Similarity Task, before and after sleep. Forty-eight participants encoded pictures from eight semantic categories, each associated with a sound. In the pre-sleep immediate test, they had to discriminate "old" (targets) from "similar" (lures) or "new" (foils) pictures. During sleep, half of the sounds were replayed in slow wave sleep (SWS) or REM sleep. Recognition, discrimination, and generalization memory indices were tested in the morning. These indices did not differ between SWS and REM TMR groups or reactivated and non-reactivated item categories. Additional results suggest a positive effect of TMR on performance for highly similar items mostly relying on mnemonic discrimination processes. During sleep, EEG activity after cue presentation increased in the delta-theta and sigma band in the SWS group, and in the beta band in the REM TMR group. These results do not support the hypothesis of a differential processing of novel memory traces when TMR is administered in distinctive physiological sleep states.
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Affiliation(s)
- Rebeca Sifuentes Ortega
- UR2NF, Neuropsychology and Functional Neuroimaging Research Unit at CRCN affiliated at Center for Research in Cognition and Neurosciences and UNI - ULB Neurosciences Institute, Université Libre de Bruxelles (ULB), Belgium
| | - Philippe Peigneux
- UR2NF, Neuropsychology and Functional Neuroimaging Research Unit at CRCN affiliated at Center for Research in Cognition and Neurosciences and UNI - ULB Neurosciences Institute, Université Libre de Bruxelles (ULB), Belgium
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3
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Guttesen AÁV, Denis D, Gaskell MG, Cairney SA. Delineating memory reactivation in sleep with verbal and non-verbal retrieval cues. Cereb Cortex 2024; 34:bhae183. [PMID: 38745557 PMCID: PMC11094403 DOI: 10.1093/cercor/bhae183] [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: 03/09/2023] [Revised: 04/12/2024] [Accepted: 04/16/2024] [Indexed: 05/16/2024] Open
Abstract
Sleep supports memory consolidation via the reactivation of newly formed memory traces. One way to investigate memory reactivation in sleep is by exposing the sleeping brain to auditory retrieval cues; a paradigm known as targeted memory reactivation. To what extent the acoustic properties of memory cues influence the effectiveness of targeted memory reactivation, however, has received limited attention. We addressed this question by exploring how verbal and non-verbal memory cues affect oscillatory activity linked to memory reactivation in sleep. Fifty-one healthy male adults learned to associate visual stimuli with spoken words (verbal cues) and environmental sounds (non-verbal cues). Subsets of the verbal and non-verbal memory cues were then replayed during sleep. The voice of the verbal cues was either matched or mismatched to learning. Memory cues (relative to unheard control cues) prompted an increase in theta/alpha and spindle power, which have been heavily implicated in sleep-associated memory processing. Moreover, verbal memory cues were associated with a stronger increase in spindle power than non-verbal memory cues. There were no significant differences between the matched and mismatched verbal cues. Our findings suggest that verbal memory cues may be most effective for triggering memory reactivation in sleep, as indicated by an amplified spindle response.
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Affiliation(s)
- Anna á V Guttesen
- Department of Psychology, University of York, York YO10 5DD, United Kingdom
- Wellcome Centre for Integrative Neuroimaging, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, United Kingdom
| | - Dan Denis
- Department of Psychology, University of York, York YO10 5DD, United Kingdom
- York Biomedical Research Institute, University of York, York YO10 5DD, United Kingdom
| | - M Gareth Gaskell
- Department of Psychology, University of York, York YO10 5DD, United Kingdom
- York Biomedical Research Institute, University of York, York YO10 5DD, United Kingdom
| | - Scott A Cairney
- Department of Psychology, University of York, York YO10 5DD, United Kingdom
- York Biomedical Research Institute, University of York, York YO10 5DD, United Kingdom
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Paller KA. Recurring memory reactivation: The offline component of learning. Neuropsychologia 2024; 196:108840. [PMID: 38417546 PMCID: PMC10981210 DOI: 10.1016/j.neuropsychologia.2024.108840] [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: 10/30/2023] [Revised: 02/19/2024] [Accepted: 02/25/2024] [Indexed: 03/01/2024]
Abstract
One can be aware of the effort needed to memorize a new fact or to recall the name of a new acquaintance. Because of experiences like this, learning can seem to have only two components, encoding information and, after some delay, retrieving information. To the contrary, learning entails additional, intervening steps that sometimes are hidden from the learner. For firmly acquiring fact and event knowledge in particular, learners are generally not cognizant of the necessity of offline consolidation. The memories that persist to be available reliably at a later time, according to the present conceptualization, are the ones we repeatedly rehearse and integrate with other knowledge, whether we do this intentionally or unknowingly, awake or asleep. This article examines the notion that learning is not a function of waking brain activity alone. What happens in the brain while we sleep also impacts memory storage, and consequently is a critical component of learning. The idea that memories can change over time and become enduring has long been present in memory research and is foundational for the concept of memory consolidation. Nevertheless, the notion that memory consolidation happens during sleep faced much resistance before eventually being firmly established. Research is still needed to elucidate the operation and repercussions of repeated reactivation during sleep. Comprehensively understanding how offline memory reactivation contributes to learning is vital for both theoretical and practical considerations.
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Affiliation(s)
- Ken A Paller
- Northwestern University, Department of Psychology, Evanston, IL, 60208, USA.
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Schmidig FJ, Geva-Sagiv M, Falach R, Yakim S, Gat Y, Sharon O, Fried I, Nir Y. A visual paired associate learning (vPAL) paradigm to study memory consolidation during sleep. J Sleep Res 2024:e14151. [PMID: 38286437 DOI: 10.1111/jsr.14151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/22/2023] [Accepted: 01/10/2024] [Indexed: 01/31/2024]
Abstract
Sleep improves the consolidation and long-term stability of newly formed memories and associations. Most research on human declarative memory and its consolidation during sleep uses word-pair associations requiring exhaustive learning. In the present study, we present the visual paired association learning (vPAL) paradigm, in which participants learn new associations between images of celebrities and animals. The vPAL is based on a one-shot exposure that resembles learning in natural conditions. We tested if vPAL can reveal a role for sleep in memory consolidation by assessing the specificity of memory recognition, and the cued recall performance, before and after sleep. We found that a daytime nap improved the stability of recognition memory and discrimination abilities compared to identical intervals of wakefulness. By contrast, cued recall of associations did not exhibit significant sleep-dependent effects. High-density electroencephalography during naps further revealed an association between sleep spindle density and stability of recognition memory. Thus, the vPAL paradigm opens new avenues for future research on sleep and memory consolidation across ages and heterogeneous populations in health and disease.
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Affiliation(s)
- Flavio Jean Schmidig
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- Department of Physiology & Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Maya Geva-Sagiv
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- Department of Neurosurgery, University of California, Los Angeles, Los Angeles, California, USA
| | - Rotem Falach
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- Department of Physiology & Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Sharon Yakim
- Edmond and Lily Safra Center for Brain Sciences (ELSC), Hebrew University, Jerusalem, Israel
| | - Yael Gat
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- Department of Physiology & Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Omer Sharon
- Center for Human Sleep Science, Department of Psychology, University of California, Berkeley, Berkeley, USA
| | - Itzhak Fried
- Department of Neurosurgery, University of California, Los Angeles, Los Angeles, California, USA
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yuval Nir
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- Department of Physiology & Pharmacology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
- The Sieratzki-Sagol Center for Sleep Medicine, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
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6
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Denis D, Cairney SA. Neural reactivation during human sleep. Emerg Top Life Sci 2023; 7:487-498. [PMID: 38054531 PMCID: PMC10754334 DOI: 10.1042/etls20230109] [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: 09/05/2023] [Revised: 11/20/2023] [Accepted: 11/23/2023] [Indexed: 12/07/2023]
Abstract
Sleep promotes memory consolidation: the process by which newly acquired memories are stabilised, strengthened, and integrated into long-term storage. Pioneering research in rodents has revealed that memory reactivation in sleep is a primary mechanism underpinning sleep's beneficial effect on memory. In this review, we consider evidence for memory reactivation processes occurring in human sleep. Converging lines of research support the view that memory reactivation occurs during human sleep, and is functionally relevant for consolidation. Electrophysiology studies have shown that memory reactivation is tightly coupled to the cardinal neural oscillations of non-rapid eye movement sleep, namely slow oscillation-spindle events. In addition, functional imaging studies have found that brain regions recruited during learning become reactivated during post-learning sleep. In sum, the current evidence paints a strong case for a mechanistic role of neural reactivation in promoting memory consolidation during human sleep.
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Affiliation(s)
- Dan Denis
- Department of Psychology, University of York, York YO10 5DD, U.K
| | - Scott A. Cairney
- Department of Psychology, University of York, York YO10 5DD, U.K
- York Biomedical Research Institute, University of York, York YO10 5DD, U.K
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7
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Liu J, Xia T, Chen D, Yao Z, Zhu M, Antony JW, Lee TMC, Hu X. Item-specific neural representations during human sleep support long-term memory. PLoS Biol 2023; 21:e3002399. [PMID: 37983253 PMCID: PMC10695382 DOI: 10.1371/journal.pbio.3002399] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 12/04/2023] [Accepted: 10/20/2023] [Indexed: 11/22/2023] Open
Abstract
Understanding how individual memories are reactivated during sleep is essential in theorizing memory consolidation. Here, we employed the targeted memory reactivation (TMR) paradigm to unobtrusively replaying auditory memory cues during human participants' slow-wave sleep (SWS). Using representational similarity analysis (RSA) on cue-elicited electroencephalogram (EEG), we found temporally segregated and functionally distinct item-specific neural representations: the early post-cue EEG activity (within 0 to 2,000 ms) contained comparable item-specific representations for memory cues and control cues, signifying effective processing of auditory cues. Critically, the later EEG activity (2,500 to 2,960 ms) showed greater item-specific representations for post-sleep remembered items than for forgotten and control cues, indicating memory reprocessing. Moreover, these later item-specific neural representations were supported by concurrently increased spindles, particularly for items that had not been tested prior to sleep. These findings elucidated how external memory cues triggered item-specific neural representations during SWS and how such representations were linked to successful long-term memory. These results will benefit future research aiming to perturb specific memory episodes during sleep.
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Affiliation(s)
- Jing Liu
- Department of Applied Social Sciences, The Hong Kong Polytechnic University, Hong Kong, People’s Republic of China
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
| | - Tao Xia
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
| | - Danni Chen
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
| | - Ziqing Yao
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
| | - Minrui Zhu
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
| | - James W. Antony
- Department of Psychology & Child Development, California Polytechnic State University, San Luis Obispo, California, United States of America
| | - Tatia M. C. Lee
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
- Laboratory of Neuropsychology and Human Neuroscience, Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
| | - Xiaoqing Hu
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
- HKU-Shenzhen Institute of Research and Innovation, Shenzhen, People’s Republic of China
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8
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Kumral D, Matzerath A, Leonhart R, Schönauer M. Spindle-dependent memory consolidation in healthy adults: A meta-analysis. Neuropsychologia 2023; 189:108661. [PMID: 37597610 DOI: 10.1016/j.neuropsychologia.2023.108661] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 06/23/2023] [Accepted: 08/12/2023] [Indexed: 08/21/2023]
Abstract
Accumulating evidence suggests a central role for sleep spindles in the consolidation of new memories. However, no meta-analysis of the association between sleep spindles and memory performance has been conducted so far. Here, we report meta-analytical evidence for spindle-memory associations and investigate how multiple factors, including memory type, spindle type, spindle characteristics, and EEG topography affect this relationship. The literature search yielded 53 studies reporting 1427 effect sizes, resulting in a small to moderate effect for the average association. We further found that spindle-memory associations were significantly stronger for procedural memory than for declarative memory. Neither spindle types nor EEG scalp topography had an impact on the strength of the spindle-memory relation, but we observed a distinct functional role of global and fast sleep spindles, especially for procedural memory. We also found a moderation effect of spindle characteristics, with power showing the largest effect sizes. Collectively, our findings suggest that sleep spindles are involved in learning, thereby representing a general physiological mechanism for memory consolidation.
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Affiliation(s)
- Deniz Kumral
- Institute of Psychology, Neuropsychology, University of Freiburg, Freiburg Im Breisgau, Germany; Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
| | - Alina Matzerath
- Institute of Psychology, Neuropsychology, University of Freiburg, Freiburg Im Breisgau, Germany
| | - Rainer Leonhart
- Institute of Psychology, Social Psychology and Methodology, University of Freiburg, Freiburg Im Breisgau, Germany
| | - Monika Schönauer
- Institute of Psychology, Neuropsychology, University of Freiburg, Freiburg Im Breisgau, Germany; Bernstein Center Freiburg, Freiburg Im Breisgau, Germany
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9
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Petzka M, Zika O, Staresina BP, Cairney SA. Better late than never: sleep still supports memory consolidation after prolonged periods of wakefulness. Learn Mem 2023; 30:245-249. [PMID: 37770107 PMCID: PMC10547377 DOI: 10.1101/lm.053660.122] [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: 03/03/2023] [Accepted: 09/04/2023] [Indexed: 10/03/2023]
Abstract
While the benefits of sleep for associative memory are well established, it is unclear whether single-item memories profit from overnight consolidation to the same extent. We addressed this question in a preregistered, online study and also investigated how the temporal proximity between learning and sleep influences overnight retention. Sleep relative to wakefulness improved retention of item and associative memories to similar extents irrespective of whether sleep occurred soon after learning or following a prolonged waking interval. Our findings highlight the far-reaching influences of sleep on memory that can arise even after substantial periods of wakefulness.
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Affiliation(s)
- Marit Petzka
- Max Planck Research Group NeuroCode, Max Planck Institute for Human Development, 14195 Berlin, Germany
- Max Planck University College London Centre for Computational Psychiatry and Aging Research, 14195 Berlin, Germany
- Institute of Psychology, University of Hamburg, 20146 Hamburg, Germany
| | - Ondrej Zika
- Max Planck Research Group NeuroCode, Max Planck Institute for Human Development, 14195 Berlin, Germany
- Max Planck University College London Centre for Computational Psychiatry and Aging Research, 14195 Berlin, Germany
| | - Bernhard P Staresina
- Department of Experimental Psychology, University of Oxford, Oxford OX2 6GG, United Kingdom
- Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford OX3 9DU, United Kingdom
| | - Scott A Cairney
- Department of Psychology, University of York, York YO10 5DD, United Kingdom
- York Biomedical Research Institute, University of York, York YO10 5DD, United Kingdom
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10
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Nebe S, Reutter M, Baker DH, Bölte J, Domes G, Gamer M, Gärtner A, Gießing C, Gurr C, Hilger K, Jawinski P, Kulke L, Lischke A, Markett S, Meier M, Merz CJ, Popov T, Puhlmann LMC, Quintana DS, Schäfer T, Schubert AL, Sperl MFJ, Vehlen A, Lonsdorf TB, Feld GB. Enhancing precision in human neuroscience. eLife 2023; 12:e85980. [PMID: 37555830 PMCID: PMC10411974 DOI: 10.7554/elife.85980] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 07/23/2023] [Indexed: 08/10/2023] Open
Abstract
Human neuroscience has always been pushing the boundary of what is measurable. During the last decade, concerns about statistical power and replicability - in science in general, but also specifically in human neuroscience - have fueled an extensive debate. One important insight from this discourse is the need for larger samples, which naturally increases statistical power. An alternative is to increase the precision of measurements, which is the focus of this review. This option is often overlooked, even though statistical power benefits from increasing precision as much as from increasing sample size. Nonetheless, precision has always been at the heart of good scientific practice in human neuroscience, with researchers relying on lab traditions or rules of thumb to ensure sufficient precision for their studies. In this review, we encourage a more systematic approach to precision. We start by introducing measurement precision and its importance for well-powered studies in human neuroscience. Then, determinants for precision in a range of neuroscientific methods (MRI, M/EEG, EDA, Eye-Tracking, and Endocrinology) are elaborated. We end by discussing how a more systematic evaluation of precision and the application of respective insights can lead to an increase in reproducibility in human neuroscience.
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Affiliation(s)
- Stephan Nebe
- Zurich Center for Neuroeconomics, Department of Economics, University of ZurichZurichSwitzerland
| | - Mario Reutter
- Department of Psychology, Julius-Maximilians-UniversityWürzburgGermany
| | - Daniel H Baker
- Department of Psychology and York Biomedical Research Institute, University of YorkYorkUnited Kingdom
| | - Jens Bölte
- Institute for Psychology, University of Münster, Otto-Creuzfeldt Center for Cognitive and Behavioral NeuroscienceMünsterGermany
| | - Gregor Domes
- Department of Biological and Clinical Psychology, University of TrierTrierGermany
- Institute for Cognitive and Affective NeuroscienceTrierGermany
| | - Matthias Gamer
- Department of Psychology, Julius-Maximilians-UniversityWürzburgGermany
| | - Anne Gärtner
- Faculty of Psychology, Technische Universität DresdenDresdenGermany
| | - Carsten Gießing
- Biological Psychology, Department of Psychology, School of Medicine and Health Sciences, Carl von Ossietzky University of OldenburgOldenburgGermany
| | - Caroline Gurr
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital, Goethe UniversityFrankfurtGermany
- Brain Imaging Center, Goethe UniversityFrankfurtGermany
| | - Kirsten Hilger
- Department of Psychology, Julius-Maximilians-UniversityWürzburgGermany
- Department of Psychology, Psychological Diagnostics and Intervention, Catholic University of Eichstätt-IngolstadtEichstättGermany
| | - Philippe Jawinski
- Department of Psychology, Humboldt-Universität zu BerlinBerlinGermany
| | - Louisa Kulke
- Department of Developmental with Educational Psychology, University of BremenBremenGermany
| | - Alexander Lischke
- Department of Psychology, Medical School HamburgHamburgGermany
- Institute of Clinical Psychology and Psychotherapy, Medical School HamburgHamburgGermany
| | - Sebastian Markett
- Department of Psychology, Humboldt-Universität zu BerlinBerlinGermany
| | - Maria Meier
- Department of Psychology, University of KonstanzKonstanzGermany
- University Psychiatric Hospitals, Child and Adolescent Psychiatric Research Department (UPKKJ), University of BaselBaselSwitzerland
| | - Christian J Merz
- Department of Cognitive Psychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr University BochumBochumGermany
| | - Tzvetan Popov
- Department of Psychology, Methods of Plasticity Research, University of ZurichZurichSwitzerland
| | - Lara MC Puhlmann
- Leibniz Institute for Resilience ResearchMainzGermany
- Max Planck Institute for Human Cognitive and Brain SciencesLeipzigGermany
| | - Daniel S Quintana
- Max Planck Institute for Human Cognitive and Brain SciencesLeipzigGermany
- NevSom, Department of Rare Disorders & Disabilities, Oslo University HospitalOsloNorway
- KG Jebsen Centre for Neurodevelopmental Disorders, University of OsloOsloNorway
- Norwegian Centre for Mental Disorders Research (NORMENT), University of OsloOsloNorway
| | - Tim Schäfer
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital, Goethe UniversityFrankfurtGermany
- Brain Imaging Center, Goethe UniversityFrankfurtGermany
| | | | - Matthias FJ Sperl
- Department of Clinical Psychology and Psychotherapy, University of GiessenGiessenGermany
- Center for Mind, Brain and Behavior, Universities of Marburg and GiessenGiessenGermany
| | - Antonia Vehlen
- Department of Biological and Clinical Psychology, University of TrierTrierGermany
| | - Tina B Lonsdorf
- Department of Systems Neuroscience, University Medical Center Hamburg-EppendorfHamburgGermany
- Department of Psychology, Biological Psychology and Cognitive Neuroscience, University of BielefeldBielefeldGermany
| | - Gordon B Feld
- Department of Clinical Psychology, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg UniversityMannheimGermany
- Department of Psychology, Heidelberg UniversityHeidelbergGermany
- Department of Addiction Behavior and Addiction Medicine, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg UniversityMannheimGermany
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg UniversityMannheimGermany
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11
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Antony JW, Schechtman E. Reap while you sleep: Consolidation of memories differs by how they were sown. Hippocampus 2023; 33:922-935. [PMID: 36973868 PMCID: PMC10429120 DOI: 10.1002/hipo.23526] [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: 11/21/2022] [Revised: 02/26/2023] [Accepted: 03/01/2023] [Indexed: 03/29/2023]
Abstract
Newly formed memories are spontaneously reactivated during sleep, leading to their strengthening. This reactivation process can be manipulated by reinstating learning-related stimuli during sleep, a technique termed targeted memory reactivation. Numerous studies have found that delivering cues during sleep improves memory for simple associations, in which one cue reactivates one tested memory. However, real-life memories often live in rich, complex networks of associations. In this review, we will examine recent forays into investigating how targeted sleep reactivation affects memories within complex paradigms, in which one cue can reactivate multiple tested memories. A common theme across studies is that reactivation consequences do not merely depend on whether memories reside in complex arrangements, but on how memories interact with one another during acquisition. We therefore emphasize how intricate study design details that alter the nature of learning and/or participant intentions impact the outcomes of sleep reactivation. In some cases, complex networks of memories interact harmoniously to bring about mutual memory benefits; in other cases, memories interact antagonistically and produce selective impairments in retrieval. Ultimately, although this burgeoning area of research has yet to be systematically explored, results suggest that the fate of reactivated stimuli within complex arrangements depends on how they were learned.
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Affiliation(s)
- James W. Antony
- Department of Psychology and Child Development, California Polytechnic State University, San Luis Obispo, California, USA
| | - Eitan Schechtman
- Department of Neurobiology and Behavior, University of California, Irvine, California, USA
- Center for Neurobiology of Learning and Memory, University of California Irvine, Irvine, California, USA
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12
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Abdellahi MEA, Koopman ACM, Treder MS, Lewis PA. Targeted memory reactivation in human REM sleep elicits detectable reactivation. eLife 2023; 12:e84324. [PMID: 37350572 PMCID: PMC10425171 DOI: 10.7554/elife.84324] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 06/22/2023] [Indexed: 06/24/2023] Open
Abstract
It is now well established that memories can reactivate during non-rapid eye movement (non-REM) sleep, but the question of whether equivalent reactivation can be detected in rapid eye movement (REM) sleep is hotly debated. To examine this, we used a technique called targeted memory reactivation (TMR) in which sounds are paired with learned material in wake, and then re-presented in subsequent sleep, in this case REM, to trigger reactivation. We then used machine learning classifiers to identify reactivation of task-related motor imagery from wake in REM sleep. Interestingly, the strength of measured reactivation positively predicted overnight performance improvement. These findings provide the first evidence for memory reactivation in human REM sleep after TMR that is directly related to brain activity during wakeful task performance.
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Affiliation(s)
- Mahmoud EA Abdellahi
- School of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC)CardiffUnited Kingdom
| | - Anne CM Koopman
- School of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC)CardiffUnited Kingdom
| | - Matthias S Treder
- School of Computer Science and Informatics, Cardiff UniversityCardiffUnited Kingdom
| | - Penelope A Lewis
- School of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC)CardiffUnited Kingdom
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13
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Brodt S, Inostroza M, Niethard N, Born J. Sleep-A brain-state serving systems memory consolidation. Neuron 2023; 111:1050-1075. [PMID: 37023710 DOI: 10.1016/j.neuron.2023.03.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/23/2023] [Accepted: 03/06/2023] [Indexed: 04/08/2023]
Abstract
Although long-term memory consolidation is supported by sleep, it is unclear how it differs from that during wakefulness. Our review, focusing on recent advances in the field, identifies the repeated replay of neuronal firing patterns as a basic mechanism triggering consolidation during sleep and wakefulness. During sleep, memory replay occurs during slow-wave sleep (SWS) in hippocampal assemblies together with ripples, thalamic spindles, neocortical slow oscillations, and noradrenergic activity. Here, hippocampal replay likely favors the transformation of hippocampus-dependent episodic memory into schema-like neocortical memory. REM sleep following SWS might balance local synaptic rescaling accompanying memory transformation with a sleep-dependent homeostatic process of global synaptic renormalization. Sleep-dependent memory transformation is intensified during early development despite the immaturity of the hippocampus. Overall, beyond its greater efficacy, sleep consolidation differs from wake consolidation mainly in that it is supported, rather than impaired, by spontaneous hippocampal replay activity possibly gating memory formation in neocortex.
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Affiliation(s)
- Svenja Brodt
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany; Max-Planck-Institute for Biological Cybernetics, Tübingen, Germany
| | - Marion Inostroza
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | - Niels Niethard
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | - Jan Born
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany; Werner Reichert Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.
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14
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Picard-Deland C, Bernardi G, Genzel L, Dresler M, Schoch SF. Memory reactivations during sleep: a neural basis of dream experiences? Trends Cogn Sci 2023; 27:568-582. [PMID: 36959079 DOI: 10.1016/j.tics.2023.02.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 02/18/2023] [Accepted: 02/28/2023] [Indexed: 03/25/2023]
Abstract
Newly encoded memory traces are spontaneously reactivated during sleep. Since their discovery in the 1990s, these memory reactivations have been discussed as a potential neural basis for dream experiences. New results from animal and human research, as well as from the rapidly growing field of sleep and dream engineering, provide essential insights into this question, and reveal both strong parallels and disparities between the two phenomena. We suggest that, although memory reactivations may contribute to subjective experiences across different states of consciousness, they are not likely to be the primary neural basis of dreaming. We identify important limitations in current research paradigms and suggest novel strategies to address this question empirically.
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Affiliation(s)
- Claudia Picard-Deland
- Dream and Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, University of Montreal, Montreal, QC, Canada
| | - Giulio Bernardi
- Institutions, Markets, Technologies (IMT) School for Advanced Studies Lucca, Lucca, Italy
| | - Lisa Genzel
- Donders Institute for Brain, Cognition, and Behaviour, Radboud University, Nijmegen, The Netherlands
| | - Martin Dresler
- Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Sarah F Schoch
- Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands; Center of Competence Sleep and Health Zurich, University of Zurich, Zurich, Switzerland.
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15
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Chen ZS, Wilson MA. How our understanding of memory replay evolves. J Neurophysiol 2023; 129:552-580. [PMID: 36752404 PMCID: PMC9988534 DOI: 10.1152/jn.00454.2022] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/20/2023] [Accepted: 01/20/2023] [Indexed: 02/09/2023] Open
Abstract
Memory reactivations and replay, widely reported in the hippocampus and cortex across species, have been implicated in memory consolidation, planning, and spatial and skill learning. Technological advances in electrophysiology, calcium imaging, and human neuroimaging techniques have enabled neuroscientists to measure large-scale neural activity with increasing spatiotemporal resolution and have provided opportunities for developing robust analytic methods to identify memory replay. In this article, we first review a large body of historically important and representative memory replay studies from the animal and human literature. We then discuss our current understanding of memory replay functions in learning, planning, and memory consolidation and further discuss the progress in computational modeling that has contributed to these improvements. Next, we review past and present analytic methods for replay analyses and discuss their limitations and challenges. Finally, looking ahead, we discuss some promising analytic methods for detecting nonstereotypical, behaviorally nondecodable structures from large-scale neural recordings. We argue that seamless integration of multisite recordings, real-time replay decoding, and closed-loop manipulation experiments will be essential for delineating the role of memory replay in a wide range of cognitive and motor functions.
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Affiliation(s)
- Zhe Sage Chen
- Department of Psychiatry, New York University Grossman School of Medicine, New York, New York, United States
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, New York, United States
- Neuroscience Institute, New York University Grossman School of Medicine, New York, New York, United States
- Department of Biomedical Engineering, New York University Tandon School of Engineering, Brooklyn, New York, United States
| | - Matthew A Wilson
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States
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16
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Whitmore NW, Paller KA. Sleep disruption by memory cues selectively weakens reactivated memories. Learn Mem 2023; 30:63-69. [PMID: 36921983 PMCID: PMC10027237 DOI: 10.1101/lm.053615.122] [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: 05/27/2022] [Accepted: 02/14/2023] [Indexed: 03/17/2023]
Abstract
A widely accepted view in memory research is that recently stored information can be reactivated during sleep, leading to memory strengthening. Two recent studies have shown that this effect can be reversed in participants with highly disrupted sleep. To test whether weakening of reactivated memories can result directly from sleep disruption, in this experiment we varied the intensity of memory reactivation cues such that some produced sleep arousals. Prior to sleep, participants (local community members) learned the locations of 75 objects, each accompanied by a sound naturally associated with that object. Location recall was tested before and after sleep, and a subset of the sounds was presented during sleep to provoke reactivation of the corresponding locations. Reactivation with sleep arousal weakened memories, unlike the improvement typically found after reactivation without sleep arousal. We conclude that reactivated memories can be selectively weakened during sleep, and that memory reactivation may strengthen or weaken memories depending on additional factors such as concurrent sleep disruption.
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Affiliation(s)
- Nathan W Whitmore
- Department of Psychology, Cognitive Neuroscience Program, Northwestern University, Evanston, Illinois 02139, USA
- Fluid Interfaces Group, Massachusetts Institute of Technology, Cambridge, Massachusetts 60208, USA
| | - Ken A Paller
- Department of Psychology, Cognitive Neuroscience Program, Northwestern University, Evanston, Illinois 02139, USA
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17
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Guttesen AÁV, Gaskell MG, Madden EV, Appleby G, Cross ZR, Cairney SA. Sleep loss disrupts the neural signature of successful learning. Cereb Cortex 2023; 33:1610-1625. [PMID: 35470400 PMCID: PMC9977378 DOI: 10.1093/cercor/bhac159] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 03/31/2022] [Accepted: 04/01/2022] [Indexed: 11/13/2022] Open
Abstract
Sleep supports memory consolidation as well as next-day learning. The influential "Active Systems" account of offline consolidation suggests that sleep-associated memory processing paves the way for new learning, but empirical evidence in support of this idea is scarce. Using a within-subjects (n = 30), crossover design, we assessed behavioral and electrophysiological indices of episodic encoding after a night of sleep or total sleep deprivation in healthy adults (aged 18-25 years) and investigated whether behavioral performance was predicted by the overnight consolidation of episodic associations from the previous day. Sleep supported memory consolidation and next-day learning as compared to sleep deprivation. However, the magnitude of this sleep-associated consolidation benefit did not significantly predict the ability to form novel memories after sleep. Interestingly, sleep deprivation prompted a qualitative change in the neural signature of encoding: Whereas 12-20 Hz beta desynchronization-an established marker of successful encoding-was observed after sleep, sleep deprivation disrupted beta desynchrony during successful learning. Taken together, these findings suggest that effective learning depends on sleep but not necessarily on sleep-associated consolidation.
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Affiliation(s)
- Anna Á V Guttesen
- Department of Psychology, University of York, Heslington, York, YO10 5DD, UK
| | - M Gareth Gaskell
- Department of Psychology, University of York, Heslington, York, YO10 5DD, UK.,York Biomedical Research Institute, University of York, Heslington, York, YO10 5DD, UK
| | - Emily V Madden
- Department of Psychology, University of York, Heslington, York, YO10 5DD, UK
| | - Gabrielle Appleby
- Department of Psychology, University of York, Heslington, York, YO10 5DD, UK
| | - Zachariah R Cross
- Cognitive Neuroscience Laboratory, Australian Research Centre for Interactive and Virtual Environments, Mawson Lakes Campus, Mawson Lakes, South Australia 5095, Australia
| | - Scott A Cairney
- Department of Psychology, University of York, Heslington, York, YO10 5DD, UK.,York Biomedical Research Institute, University of York, Heslington, York, YO10 5DD, UK
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18
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Abdellahi MEA, Koopman ACM, Treder MS, Lewis PA. Targeting targeted memory reactivation: Characteristics of cued reactivation in sleep. Neuroimage 2023; 266:119820. [PMID: 36535324 DOI: 10.1016/j.neuroimage.2022.119820] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 11/16/2022] [Accepted: 12/15/2022] [Indexed: 12/23/2022] Open
Abstract
Targeted memory reactivation (TMR) is a technique in which sensory cues associated with memories during wake are used to trigger memory reactivation during subsequent sleep. The characteristics of such cued reactivation, and the optimal placement of TMR cues, remain to be determined. We built an EEG classification pipeline that discriminated reactivation of right- and left-handed movements and found that cues which fall on the up-going transition of the slow oscillation (SO) are more likely to elicit a classifiable reactivation. We also used a novel machine learning pipeline to predict the likelihood of eliciting a classifiable reactivation after each TMR cue using the presence of spindles and features of SOs. Finally, we found that reactivations occurred either immediately after the cue or one second later. These findings greatly extend our understanding of memory reactivation and pave the way for development of wearable technologies to efficiently enhance memory through cueing in sleep.
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Affiliation(s)
- Mahmoud E A Abdellahi
- School of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff CF24 4HQ, United Kingdom.
| | - Anne C M Koopman
- School of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff CF24 4HQ, United Kingdom
| | - Matthias S Treder
- School of Computer Science and Informatics, Cardiff University, Cardiff CF24 3AA, United Kingdom
| | - Penelope A Lewis
- School of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff CF24 4HQ, United Kingdom
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19
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Roüast NM, Schönauer M. Continuously changing memories: a framework for proactive and non-linear consolidation. Trends Neurosci 2023; 46:8-19. [PMID: 36428193 DOI: 10.1016/j.tins.2022.10.013] [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: 08/11/2022] [Revised: 10/10/2022] [Accepted: 10/27/2022] [Indexed: 11/23/2022]
Abstract
The traditional view of long-term memory is that memory traces mature in a predetermined 'linear' process: their neural substrate shifts from rapidly plastic medial temporal regions towards stable neocortical networks. We propose that memories remain malleable, not by repeated reinstantiations of this linear process but instead via dynamic routes of proactive and non-linear consolidation: memories change, their trajectory is flexible and reversible, and their physical basis develops continuously according to anticipated demands. Studies demonstrating memory updating, increasing hippocampal dependence to support adaptive use, and rapid neocortical plasticity provide evidence for continued non-linear consolidation. Although anticipated demand can affect all stages of memory formation, the extent to which it shapes the physical memory trace repeatedly and proactively will require further dedicated research.
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Affiliation(s)
- Nora Malika Roüast
- Institute for Psychology, Neuropsychology, University of Freiburg, Freiburg, Germany.
| | - Monika Schönauer
- Institute for Psychology, Neuropsychology, University of Freiburg, Freiburg, Germany.
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20
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Barry DN, Love BC. A neural network account of memory replay and knowledge consolidation. Cereb Cortex 2022; 33:83-95. [PMID: 35213689 PMCID: PMC9758580 DOI: 10.1093/cercor/bhac054] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 01/25/2022] [Accepted: 01/26/2022] [Indexed: 11/15/2022] Open
Abstract
Replay can consolidate memories through offline neural reactivation related to past experiences. Category knowledge is learned across multiple experiences, and its subsequent generalization is promoted by consolidation and replay during rest and sleep. However, aspects of replay are difficult to determine from neuroimaging studies. We provided insights into category knowledge replay by simulating these processes in a neural network which approximated the roles of the human ventral visual stream and hippocampus. Generative replay, akin to imagining new category instances, facilitated generalization to new experiences. Consolidation-related replay may therefore help to prepare us for the future as much as remember the past. Generative replay was more effective in later network layers functionally similar to the lateral occipital cortex than layers corresponding to early visual cortex, drawing a distinction between neural replay and its relevance to consolidation. Category replay was most beneficial for newly acquired knowledge, suggesting replay helps us adapt to changes in our environment. Finally, we present a novel mechanism for the observation that the brain selectively consolidates weaker information, namely a reinforcement learning process in which categories were replayed according to their contribution to network performance. This reinforces the idea of consolidation-related replay as an active rather than passive process.
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Affiliation(s)
- Daniel N Barry
- Department of Experimental Psychology, University College London, 26 Bedford Way, London WC1H0AP, UK
| | - Bradley C Love
- Department of Experimental Psychology, University College London, 26 Bedford Way, London WC1H0AP, UK
- The Alan Turing Institute, 96 Euston Road, London NW12DB, UK
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21
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Affiliation(s)
- Eitan Schechtman
- Department of Neurobiology and Behavior, University of California, Irvine, California 92697, USA
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22
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Singh D, Norman KA, Schapiro AC. A model of autonomous interactions between hippocampus and neocortex driving sleep-dependent memory consolidation. Proc Natl Acad Sci U S A 2022; 119:e2123432119. [PMID: 36279437 PMCID: PMC9636926 DOI: 10.1073/pnas.2123432119] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 08/11/2022] [Indexed: 08/04/2023] Open
Abstract
How do we build up our knowledge of the world over time? Many theories of memory formation and consolidation have posited that the hippocampus stores new information, then "teaches" this information to the neocortex over time, especially during sleep. But it is unclear, mechanistically, how this actually works-How are these systems able to interact during periods with virtually no environmental input to accomplish useful learning and shifts in representation? We provide a framework for thinking about this question, with neural network model simulations serving as demonstrations. The model is composed of hippocampus and neocortical areas, which replay memories and interact with one another completely autonomously during simulated sleep. Oscillations are leveraged to support error-driven learning that leads to useful changes in memory representation and behavior. The model has a non-rapid eye movement (NREM) sleep stage, where dynamics between the hippocampus and neocortex are tightly coupled, with the hippocampus helping neocortex to reinstate high-fidelity versions of new attractors, and a REM sleep stage, where neocortex is able to more freely explore existing attractors. We find that alternating between NREM and REM sleep stages, which alternately focuses the model's replay on recent and remote information, facilitates graceful continual learning. We thus provide an account of how the hippocampus and neocortex can interact without any external input during sleep to drive useful new cortical learning and to protect old knowledge as new information is integrated.
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Affiliation(s)
- Dhairyya Singh
- Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104
| | - Kenneth A. Norman
- Department of Psychology, Princeton University, Princeton, NJ 08540
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08540
| | - Anna C. Schapiro
- Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104
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23
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Electrophysiological markers of memory consolidation in the human brain when memories are reactivated during sleep. Proc Natl Acad Sci U S A 2022; 119:e2123430119. [PMID: 36279460 PMCID: PMC9636913 DOI: 10.1073/pnas.2123430119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Sleep contributes to memory consolidation, we presume, because memories are replayed during sleep. Understanding this aspect of consolidation can help with optimizing normal learning in many contexts and with treating memory disorders and other diseases. Here, we systematically manipulated sleep-based processing using targeted memory reactivation; brief sounds coupled with presleep learning were quietly presented again during sleep, producing 1) recall improvements for specific spatial memories associated with those sounds and 2) physiological responses in the sleep electroencephalogram. Neural activity in the hippocampus and adjacent medial temporal cortex was thus found in association with memory consolidation during sleep. These findings advance understanding of consolidation by linking beneficial memory changes during sleep to both memory reactivation and specific patterns of brain activity. Human accomplishments depend on learning, and effective learning depends on consolidation. Consolidation is the process whereby new memories are gradually stored in an enduring way in the brain so that they can be available when needed. For factual or event knowledge, consolidation is thought to progress during sleep as well as during waking states and to be mediated by interactions between hippocampal and neocortical networks. However, consolidation is difficult to observe directly but rather is inferred through behavioral observations. Here, we investigated overnight memory change by measuring electrical activity in and near the hippocampus. Electroencephalographic (EEG) recordings were made in five patients from electrodes implanted to determine whether a surgical treatment could relieve their seizure disorders. One night, while each patient slept in a hospital monitoring room, we recorded electrophysiological responses to 10 to 20 specific sounds that were presented very quietly, to avoid arousal. Half of the sounds had been associated with objects and their precise spatial locations that patients learned before sleep. After sleep, we found systematic improvements in spatial recall, replicating prior results. We assume that when the sounds were presented during sleep, they reactivated and strengthened corresponding spatial memories. Notably, the sounds also elicited oscillatory intracranial EEG activity, including increases in theta, sigma, and gamma EEG bands. Gamma responses, in particular, were consistently associated with the degree of improvement in spatial memory exhibited after sleep. We thus conclude that this electrophysiological activity in the hippocampus and adjacent medial temporal cortex reflects sleep-based enhancement of memory storage.
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24
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Ngo HVV, Staresina BP. Shaping overnight consolidation via slow-oscillation closed-loop targeted memory reactivation. Proc Natl Acad Sci U S A 2022; 119:e2123428119. [PMID: 36279449 PMCID: PMC9636934 DOI: 10.1073/pnas.2123428119] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 05/19/2022] [Indexed: 11/23/2022] Open
Abstract
Sleep constitutes a privileged state for new memories to reactivate and consolidate. Previous work has demonstrated that consolidation can be bolstered experimentally either via delivery of reminder cues (targeted memory reactivation [TMR]) or via noninvasive brain stimulation geared toward enhancing endogenous sleep rhythms. Here, we combined both approaches, controlling the timing of TMR cues with respect to ongoing slow-oscillation (SO) phases. Prior to sleep, participants learned associations between unique words and a set of repeating images (e.g., car) while hearing a prototypical image sound (e.g., engine starting). Memory performance on an immediate test vs. a test the next morning quantified overnight memory consolidation. Importantly, two image sounds were designated as TMR cues, with one cue delivered at SO UP states and the other delivered at SO DOWN states. A novel sound was used as a TMR control condition. Behavioral results revealed a significant reduction of overnight forgetting for words associated with UP-state TMR compared with words associated with DOWN-state TMR. Electrophysiological results showed that UP-state cueing led to enhancement of the ongoing UP state and was followed by greater spindle power than DOWN-state cueing. Moreover, UP-state (and not DOWN-state) cueing led to reinstatement of target image representations. Together, these results unveil the behavioral and mechanistic effects of delivering reminder cues at specific phases of endogenous sleep rhythms and mark an important step for the endeavor to experimentally modulate memories during sleep.
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Affiliation(s)
- Hong-Viet V. Ngo
- Department of Psychology, University of Lübeck, 23562 Lübeck, Germany
- Centre for Brain, Behavior and Metabolism, University of Lübeck, 23562 Lübeck, Germany
| | - Bernhard P. Staresina
- Department of Experimental Psychology, University of Oxford, Oxford OX2 6GG, United Kingdom
- Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford OX3 9DU, United Kingdom
- School of Psychology, University of Birmingham, Birmingham B15 2TT, United Kingdom
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25
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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
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26
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Abstract
In human neuroscience, studies of cognition are rarely grounded in non-task-evoked, 'spontaneous' neural activity. Indeed, studies of spontaneous activity tend to focus predominantly on intrinsic neural patterns (for example, resting-state networks). Taking a 'representation-rich' approach bridges the gap between cognition and resting-state communities: this approach relies on decoding task-related representations from spontaneous neural activity, allowing quantification of the representational content and rich dynamics of such activity. For example, if we know the neural representation of an episodic memory, we can decode its subsequent replay during rest. We argue that such an approach advances cognitive research beyond a focus on immediate task demand and provides insight into the functional relevance of the intrinsic neural pattern (for example, the default mode network). This in turn enables a greater integration between human and animal neuroscience, facilitating experimental testing of theoretical accounts of intrinsic activity, and opening new avenues of research in psychiatry.
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27
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Whitehurst LN, Subramoniam A, Krystal A, Prather AA. Links between the brain and body during sleep: implications for memory processing. Trends Neurosci 2022; 45:212-223. [PMID: 35074220 DOI: 10.1016/j.tins.2021.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 11/30/2021] [Accepted: 12/21/2021] [Indexed: 10/19/2022]
Abstract
Sleep is intimately related to memory processes. The established view is that the transformation of experiences into long-term memories is linked to sleep-related CNS function. However, there is increasing evidence that the autonomic nervous system (ANS), long recognized to modulate cognition during waking, can impact memory processing during sleep. Here, we review human research that examines the role of autonomic activity and sleep in memory formation. We argue that autonomic activity during sleep may set the stage for the CNS dynamics associated with sleep and memory stability and integration. Further, we consider how the link between ANS activity and polysomnographic markers of sleep may help elucidate both healthy and pathological cognitive aging in humans.
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Affiliation(s)
| | | | - Andrew Krystal
- Department of Psychiatry and Behavioral Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Aric A Prather
- Department of Psychiatry and Behavioral Sciences, University of California, San Francisco, San Francisco, CA, USA
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28
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Prefrontal Transcranial Direct Current Stimulation Globally Improves Learning but Does Not Selectively Potentiate the Benefits of Targeted Memory Reactivation on Awake Memory Consolidation. Brain Sci 2021; 11:brainsci11081104. [PMID: 34439722 PMCID: PMC8393859 DOI: 10.3390/brainsci11081104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 08/17/2021] [Accepted: 08/19/2021] [Indexed: 12/04/2022] Open
Abstract
Targeted memory reactivation (TMR) and transcranial direct current stimulation (tDCS) can enhance memory consolidation. It is currently unknown whether TMR reinforced by simultaneous tDCS has superior efficacy. In this study, we investigated the complementary effect of TMR and bilateral tDCS on the consolidation of emotionally neutral and negative declarative memories. Participants learned neutral and negative word pairs. Each word pair was presented with an emotionally compatible sound. Following learning, participants spent a 20 min retention interval awake under four possible conditions: (1) TMR alone (i.e., replay of 50% of the associated sounds), (2) TMR combined with anodal stimulation of the left DLPFC, (3) TMR combined with anodal stimulation of the right DLPFC and (4) TMR with sham tDCS. Results evidenced selective memory enhancement for the replayed stimuli in the TMR-only and TMR-sham conditions, which confirms a specific effect of TMR on memory. However, memory was enhanced at higher levels for all learned items (irrespective of TMR) in the TMR-anodal right and TMR-anodal left tDCS conditions, suggesting that the beneficial effects of tDCS overshadow the specific effects of TMR. Emotionally negative memories were not modulated by tDCS hemispheric polarity. We conclude that electrical stimulation of the DLPFC during the post-learning period globally benefits memory consolidation but does not potentiate the specific benefits of TMR.
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Abstract
We rely on our long-term memories to guide future behaviors, making it adaptive to prioritize the retention of goal-relevant, salient information in memory. In this review, we discuss findings from rodent and human research to demonstrate that active processes during post-encoding consolidation support the selective stabilization of recent experience into adaptive, long-term memories. Building upon literatures focused on dynamics at the cellular level, we highlight that consolidation also transforms memories at the systems level to support future goal-relevant behavior, resulting in more generalized memory traces in the brain and behavior. We synthesize previous literatures spanning animal research, human cognitive neuroscience, and cognitive psychology to propose an integrative framework for adaptive consolidation by which goal-relevant memoranda are "tagged" for subsequent consolidation, resulting in selective transformations to the structure of memories that support flexible, goal-relevant behaviors.
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Schreiner T, Petzka M, Staudigl T, Staresina BP. Endogenous memory reactivation during sleep in humans is clocked by slow oscillation-spindle complexes. Nat Commun 2021; 12:3112. [PMID: 34035303 PMCID: PMC8149676 DOI: 10.1038/s41467-021-23520-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 05/04/2021] [Indexed: 02/04/2023] Open
Abstract
Sleep is thought to support memory consolidation via reactivation of prior experiences, with particular electrophysiological sleep signatures (slow oscillations (SOs) and sleep spindles) gating the information flow between relevant brain areas. However, empirical evidence for a role of endogenous memory reactivation (i.e., without experimentally delivered memory cues) for consolidation in humans is lacking. Here, we devised a paradigm in which participants acquired associative memories before taking a nap. Multivariate decoding was then used to capture endogenous memory reactivation during non-rapid eye movement (NREM) sleep in surface EEG recordings. Our results reveal reactivation of learning material during SO-spindle complexes, with the precision of SO-spindle coupling predicting reactivation strength. Critically, reactivation strength (i.e. classifier evidence in favor of the previously studied stimulus category) in turn predicts the level of consolidation across participants. These results elucidate the memory function of sleep in humans and emphasize the importance of SOs and spindles in clocking endogenous consolidation processes.
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Affiliation(s)
- Thomas Schreiner
- Department of Psychology, Ludwig-Maximilians-University, Munich, Germany
| | - Marit Petzka
- School of Psychology and Centre for Human Brain Health, University of Birmingham, Birmingham, UK
| | - Tobias Staudigl
- Department of Psychology, Ludwig-Maximilians-University, Munich, Germany
| | - Bernhard P Staresina
- School of Psychology and Centre for Human Brain Health, University of Birmingham, Birmingham, UK.
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A new application of TMR: A study on implicit self-esteem. CURRENT PSYCHOLOGY 2021. [DOI: 10.1007/s12144-021-01883-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Picard-Deland C, Aumont T, Samson-Richer A, Paquette T, Nielsen T. Whole-body procedural learning benefits from targeted memory reactivation in REM sleep and task-related dreaming. Neurobiol Learn Mem 2021; 183:107460. [PMID: 34015442 DOI: 10.1016/j.nlm.2021.107460] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 04/20/2021] [Accepted: 05/12/2021] [Indexed: 10/21/2022]
Abstract
Sleep facilitates memory consolidation through offline reactivations of memory traces. Dreaming may play a role in memory improvement and may reflect these memory reactivations. To experimentally address this question, we used targeted memory reactivation (TMR), i.e., application, during sleep, of a stimulus that was previously associated with learning, to assess whether it influences task-related dream imagery (or task-dream reactivations). Specifically, we asked if TMR or task-dream reactivations in either slow-wave (SWS) or rapid eye movement (REM) sleep benefit whole-body procedural learning. Healthy participants completed a virtual reality (VR) flying task prior to and following a morning nap or rest period during which task-associated tones were readministered in either SWS, REM sleep, wake or not at all. Findings indicate that learning benefits most from TMR when applied in REM sleep compared to a Control-sleep group. REM dreams that reactivated kinesthetic elements of the VR task (e.g., flying, accelerating) were also associated with higher improvement on the task than were dreams that reactivated visual elements (e.g., landscapes) or that had no reactivations. TMR did not itself influence dream content but its effects on performance were greater when coexisting with task-dream reactivations in REM sleep. Findings may help explain the mechanistic relationships between dream and memory reactivations and may contribute to the development of sleep-based methods to optimize complex skill learning.
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Affiliation(s)
- Claudia Picard-Deland
- Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Québec, Canada; Department of Neuroscience, Université de Montréal, Montréal, Québec, Canada
| | - Tomy Aumont
- Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Québec, Canada; Department of Biomedical Sciences, Université de Montréal, Montréal, Québec, Canada
| | - Arnaud Samson-Richer
- Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Québec, Canada
| | - Tyna Paquette
- Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Québec, Canada
| | - Tore Nielsen
- Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Québec, Canada; Department of Psychiatry and Addictology, Université de Montréal, Montréal, Québec, Canada.
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MacDonald KJ, Cote KA. Contributions of post-learning REM and NREM sleep to memory retrieval. Sleep Med Rev 2021; 59:101453. [PMID: 33588273 DOI: 10.1016/j.smrv.2021.101453] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 12/10/2020] [Accepted: 12/23/2020] [Indexed: 02/06/2023]
Abstract
It has become clear that sleep after learning has beneficial effects on the later retrieval of newly acquired memories. The neural mechanisms underlying these effects are becoming increasingly clear as well, particularly those of non-REM sleep. However, much is still unknown about the sleep and memory relationship: the sleep state or features of sleep physiology that associate with memory performance often vary by task or experimental design, and the nature of this variability is not entirely clear. This paper describes pertinent features of sleep physiology and provides a detailed review of the scientific literature indicating beneficial effects of post-learning sleep on memory retrieval. This paper additionally introduces a hypothesis which attributes these beneficial effects of post-learning sleep to separable processes of memory reinforcement and memory refinement whereby reinforcement supports one's ability to retrieve a given memory and refinement supports the precision of that memory retrieval in the context of competitive alternatives. It is observed that features of non-REM sleep are involved in a post-learning substantiation of memory representations that benefit memory performance; thus, memory reinforcement is primarily attributed to non-REM sleep. Memory refinement is primarily attributed to REM sleep given evidence of bidirectional synaptic plasticity in REM sleep and findings from studies of selective REM sleep deprivation.
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Wan H, Wang X, Chen Y, Jiang B, Chen Y, Hu W, Zhang K, Shao X. Sleep-Related Hypermotor Epilepsy: Etiology, Electro-Clinical Features, and Therapeutic Strategies. Nat Sci Sleep 2021; 13:2065-2084. [PMID: 34803415 PMCID: PMC8598206 DOI: 10.2147/nss.s330986] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Accepted: 10/21/2021] [Indexed: 12/31/2022] Open
Abstract
Sleep-related hypermotor epilepsy (SHE) is a group of clinical syndromes with heterogeneous etiologies. SHE is difficult to diagnose and treat in the early stages due to its diverse clinical manifestations and difficulties in differentiating from non-epileptic events, which seriously affect patients' quality of life and social behavior. The overall prognosis for SHE is unsatisfactory, but different etiologies affect patients' prognoses. Surgical treatment is an effective method for carefully selected patients with refractory SHE; nevertheless, preoperative assessment remains challenging because of the low sensitivity of noninvasive scalp electroencephalogram and imaging to detect abnormalities. However, through a careful analysis of semiology, the clinician can deduce the potential epileptogenic zone. This paper summarizes the research status of the background, etiology, electro-clinical features, diagnostic criteria, prognosis, and treatment of SHE to provide a more in-depth understanding of its pathophysiological mechanism, improve the accuracy in the diagnosis of this group of syndromes, and further explore more targeted therapy plans.
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Affiliation(s)
- Huijuan Wan
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, People's Republic of China.,China National Clinical Research Center for Neurological Diseases (NCRC-ND), Beijing, People's Republic of China.,Department of Neurology, First Affiliated Hospital, Xiamen University, Xiamen, People's Republic of China
| | - Xing Wang
- Department of Neurology, Chongqing University Central Hospital, Chongqing Emergency Medical Centre, Chongqing, People's Republic of China
| | - Yiyi Chen
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, People's Republic of China.,China National Clinical Research Center for Neurological Diseases (NCRC-ND), Beijing, People's Republic of China
| | - Bin Jiang
- Department of Neurology, First Affiliated Hospital, Xiamen University, Xiamen, People's Republic of China
| | - Yangmei Chen
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China
| | - Wenhan Hu
- Beijing Neurosurgical Institute, Capital Medical University, Beijing, People's Republic of China
| | - Kai Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, People's Republic of China
| | - Xiaoqiu Shao
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, People's Republic of China.,China National Clinical Research Center for Neurological Diseases (NCRC-ND), Beijing, People's Republic of China
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35
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Reactivation during sleep with incomplete reminder cues rather than complete ones stabilizes long-term memory in humans. Commun Biol 2020; 3:733. [PMID: 33277601 PMCID: PMC7718244 DOI: 10.1038/s42003-020-01457-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 10/31/2020] [Indexed: 01/15/2023] Open
Abstract
Reactivation by reminder cues labilizes memories during wakefulness, requiring reconsolidation to persist. In contrast, during sleep, cued reactivation seems to directly stabilize memories. In reconsolidation, incomplete reminders are more effective in reactivating memories than complete reminders by inducing a mismatch, i.e. a discrepancy between expected and actual events. Whether mismatch is likewise detected during sleep is unclear. Here we test whether cued reactivation during sleep is more effective for mismatch-inducing incomplete than complete reminders. We first establish that only incomplete but not complete reminders labilize memories during wakefulness. When complete or incomplete reminders are presented during 40-min sleep, both reminders are equally effective in stabilizing memories. However, when extending the retention interval for another 7 hours (following 40-min sleep), only incomplete but not complete reminders stabilize memories, regardless of the extension containing wakefulness or sleep. We propose that, during sleep, only incomplete reminders initiate long-term memory stabilization via mismatch detection. Forcato et al. show that incomplete reminder cues rather than complete ones stabilize human memories during sleep. This study suggests that only incomplete reminders initiate long-term memory stabilization via mismatch detection during sleep.
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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.
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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; , ,
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37
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Abstract
While in the past much of our knowledge about memory representations in the brain has relied on loss-of-function studies in which whole brain regions were temporarily inactivated or permanently lesioned, the recent development of new methods has ushered in a new era of downright "engram excitement." Animal research is now able to specifically label, track, and manipulate engram cells in the brain. While early studies have mostly focused on single brain regions like the hippocampus, recently more and more evidence for brain-wide distributed engram networks is emerging. Memory research in humans has also picked up pace, fueled by promising magnetic resonance imaging (MRI)-based methods like diffusion-weighted MRI (DW-MRI) and brain decoding. In this review, we will outline recent advancements in engram research, with a focus on human data and neocortical representations. We will illustrate the available noninvasive methods for the detection of engrams in different neocortical regions like the medial prefrontal cortex and the posterior parietal cortex and discuss evidence for systems consolidation and parallel memory encoding. Finally, we will explore how reactivation and prior knowledge can lead to and enhance engram formation in the neocortex.
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38
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Hahn MA, Heib D, Schabus M, Hoedlmoser K, Helfrich RF. Slow oscillation-spindle coupling predicts enhanced memory formation from childhood to adolescence. eLife 2020; 9:e53730. [PMID: 32579108 PMCID: PMC7314542 DOI: 10.7554/elife.53730] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 05/21/2020] [Indexed: 12/14/2022] Open
Abstract
Precise temporal coordination of slow oscillations (SO) and sleep spindles is a fundamental mechanism of sleep-dependent memory consolidation. SO and spindle morphology changes considerably throughout development. Critically, it remains unknown how the precise temporal coordination of these two sleep oscillations develops during brain maturation and whether their synchronization indexes the development of memory networks. Here, we use a longitudinal study design spanning from childhood to adolescence, where participants underwent polysomnography and performed a declarative word-pair learning task. Performance on the memory task was better during adolescence. After disentangling oscillatory components from 1/f activity, we found frequency shifts within SO and spindle frequency bands. Consequently, we devised an individualized cross-frequency coupling approach, which demonstrates that SO-spindle coupling strength increases during maturation. Critically, this increase indicated enhanced memory formation from childhood to adolescence. Our results provide evidence that improved coordination between SOs and spindles indexes the development of sleep-dependent memory networks.
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Affiliation(s)
- Michael A Hahn
- Department of Psychology, Laboratory for Sleep, Cognition and Consciousness Research, University of SalzburgSalzburgAustria
- Centre for Cognitive Neuroscience Salzburg (CCNS), University of SalzburgSalzburgAustria
| | - Dominik Heib
- Department of Psychology, Laboratory for Sleep, Cognition and Consciousness Research, University of SalzburgSalzburgAustria
- Centre for Cognitive Neuroscience Salzburg (CCNS), University of SalzburgSalzburgAustria
| | - Manuel Schabus
- Department of Psychology, Laboratory for Sleep, Cognition and Consciousness Research, University of SalzburgSalzburgAustria
- Centre for Cognitive Neuroscience Salzburg (CCNS), University of SalzburgSalzburgAustria
| | - Kerstin Hoedlmoser
- Department of Psychology, Laboratory for Sleep, Cognition and Consciousness Research, University of SalzburgSalzburgAustria
- Centre for Cognitive Neuroscience Salzburg (CCNS), University of SalzburgSalzburgAustria
| | - Randolph F Helfrich
- Hertie-Institute for Clinical Brain Research, University of TübingenTübingenGermany
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39
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40
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Samanta A, Alonso A, Genzel L. Memory reactivations and consolidation: considering neuromodulators across wake and sleep. CURRENT OPINION IN PHYSIOLOGY 2020. [DOI: 10.1016/j.cophys.2020.01.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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41
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Eichenlaub JB, Biswal S, Peled N, Rivilis N, Golby AJ, Lee JW, Westover MB, Halgren E, Cash SS. Reactivation of Motor-Related Gamma Activity in Human NREM Sleep. Front Neurosci 2020; 14:449. [PMID: 32477056 PMCID: PMC7235414 DOI: 10.3389/fnins.2020.00449] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Accepted: 04/14/2020] [Indexed: 12/26/2022] Open
Abstract
Models of memory consolidation posit a central role for reactivation of brain activity patterns during sleep, especially in non-Rapid Eye Movement (NREM) sleep. While such "replay" of recent waking experiences has been well-demonstrated in rodents, electrophysiological evidence of reactivation in human sleep is still largely lacking. In this intracranial study in patients with epilepsy (N = 9) we explored the spontaneous electroencephalographic reactivation during sleep of spatial patterns of brain activity evoked by motor learning. We first extracted the gamma-band (60-140 Hz) patterns underlying finger movements during a tapping task and underlying no-movement during a short rest period just prior to the task, and trained a binary classifier to discriminate between motor movements vs. rest. We then used the trained model on NREM sleep data immediately after the task and on NREM sleep during a control sleep period preceding the task. Compared with the control sleep period, we found, at the subject level, an increase in the detection rate of motor-related patterns during sleep following the task, but without association with performance changes. These data provide electrophysiological support for the reoccurrence in NREM sleep of the neural activity related to previous waking experience, i.e. that a basic tenet of the reactivation theory does occur in human sleep.
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Affiliation(s)
- Jean-Baptiste Eichenlaub
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Siddharth Biswal
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Noam Peled
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Nicole Rivilis
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Alexandra J. Golby
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Jong Woo Lee
- Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - M. Brandon Westover
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Eric Halgren
- Departments of Radiology and Neuroscience, Kavli Institute for Brain and Mind, University of California, San Diego, San Diego, CA, United States
| | - Sydney S. Cash
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
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42
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Phase-based coordination of hippocampal and neocortical oscillations during human sleep. Commun Biol 2020; 3:176. [PMID: 32313064 PMCID: PMC7170909 DOI: 10.1038/s42003-020-0913-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 03/25/2020] [Indexed: 01/09/2023] Open
Abstract
During sleep, new memories undergo a gradual transfer from hippocampal (HPC) to neocortical (NC) sites. Precisely timed neural oscillations are thought to mediate this sleep-dependent memory consolidation, but exactly how sleep oscillations instantiate the HPC-NC dialog remains elusive. Employing overnight invasive electroencephalography in ten neurosurgical patients, we identified three broad classes of phase-based communication between HPC and lateral temporal NC. First, we observed interregional phase synchrony for non-rapid eye movement (NREM) spindles, and N2 and rapid eye movement (REM) theta activity. Second, we found asymmetrical N3 cross-frequency phase-amplitude coupling between HPC slow oscillations (SOs) and NC activity spanning the delta to high-gamma/ripple bands, but not in the opposite direction. Lastly, N2 theta and NREM spindle synchrony were themselves modulated by HPC SOs. These forms of interregional communication emphasize the role of HPC SOs in the HPC-NC dialog, and may offer a physiological basis for the sleep-dependent reorganization of mnemonic content.
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43
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Pöhlchen D, Pawlizki A, Gais S, Schönauer M. Evidence against a large effect of sleep in protecting verbal memories from interference. J Sleep Res 2020; 30:e13042. [PMID: 32311167 DOI: 10.1111/jsr.13042] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 02/08/2020] [Accepted: 03/17/2020] [Indexed: 01/02/2023]
Abstract
The human brain has evolved to acquire novel information rapidly while serving the need to store long-term memories in a stable and lasting form. Presenting interfering information directly after learning can lead to forgetting of the original material. It has been suggested that sleep aids the stabilization of new memories and protects them from interference. Here, we aim to replicate in two separate experiments the claim that sleep protects memories from retroactive interference (Current Biology, 16, 2006 and 1290; PLoS ONE, 4, 2009 and e4117). We let participants study wordlists before letting them sleep for an afternoon nap or for a full night. In a control condition, subjects stayed awake for the same amount of time. After the consolidation interval, participants learnt an interfering wordlist and were tested on memory of the original wordlist. Sleep did not stabilize memory for the original wordlist in either study. We discuss our findings in the light of recent advances in computational neuroscience, and conclude that the stabilizing effect of sleep against interference has been overestimated.
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Affiliation(s)
- Dorothee Pöhlchen
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tubingen, Germany.,International Max Planck Research School - Translational Psychiatry (IMPRS-TP), Max Planck Institute of Psychiatry, Munich, Germany
| | - Annedore Pawlizki
- Department of Psychology, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Steffen Gais
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tubingen, Germany
| | - Monika Schönauer
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tubingen, Germany.,Department of Psychology, Princeton University, Princeton, NJ, USA.,Institute of Neuropsychology, University of Freiburg, Freiburg, Germany
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44
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Tahmasian M, Samea F, Khazaie H, Zarei M, Kharabian Masouleh S, Hoffstaedter F, Camilleri J, Kochunov P, Yeo BTT, Eickhoff SB, Valk SL. The interrelation of sleep and mental and physical health is anchored in grey-matter neuroanatomy and under genetic control. Commun Biol 2020; 3:171. [PMID: 32273564 PMCID: PMC7145855 DOI: 10.1038/s42003-020-0892-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 03/16/2020] [Indexed: 12/15/2022] Open
Abstract
Humans need about seven to nine hours of sleep per night. Sleep habits are heritable, associated with brain function and structure, and intrinsically related to well-being, mental, and physical health. However, the biological basis of the interplay of sleep and health is incompletely understood. Here we show, by combining neuroimaging and behavioral genetic approaches in two independent large-scale datasets (HCP (n = 1106), age range: 22-37, eNKI (n = 783), age range: 12-85), that sleep, mental, and physical health have a shared neurobiological basis in grey matter anatomy; and that these relationships are driven by shared genetic factors. Though local associations between sleep and cortical thickness were inconsistent across samples, we identified two robust latent components, highlighting the multivariate interdigitation of sleep, intelligence, BMI, depression, and macroscale cortical structure. Our observations provide a system-level perspective on the interrelation of sleep, mental, and physical conditions, anchored in grey-matter neuroanatomy.
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Affiliation(s)
- Masoud Tahmasian
- Institute of Medical Science and Technology, Shahid Beheshti University, Tehran, Iran
| | - Fateme Samea
- Institute of Medical Science and Technology, Shahid Beheshti University, Tehran, Iran
| | - Habibolah Khazaie
- Sleep Disorders Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Mojtaba Zarei
- Institute of Medical Science and Technology, Shahid Beheshti University, Tehran, Iran
| | - Shahrzad Kharabian Masouleh
- Institute of Neuroscience and Medicine (INM-7: Brain and Behaviour), Research Centre Jülich, 52425, Jülich, Germany
- Institute of Systems Neuroscience, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
| | - Felix Hoffstaedter
- Institute of Neuroscience and Medicine (INM-7: Brain and Behaviour), Research Centre Jülich, 52425, Jülich, Germany
- Institute of Systems Neuroscience, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
| | - Julia Camilleri
- Institute of Neuroscience and Medicine (INM-7: Brain and Behaviour), Research Centre Jülich, 52425, Jülich, Germany
- Institute of Systems Neuroscience, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
| | - Peter Kochunov
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - B T Thomas Yeo
- Department of Electrical and Computer Engineering, Clinical Imaging Research Centre, N.1 Institute for Health and Memory Networks Program, National University of Singapore, Singapore, 119077, Singapore
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, 02114, USA
- Centre for Sleep and Cognition, National University of Singapore, Singapore, 119077, Singapore
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, 119077, Singapore
| | - Simon Bodo Eickhoff
- Institute of Neuroscience and Medicine (INM-7: Brain and Behaviour), Research Centre Jülich, 52425, Jülich, Germany
- Institute of Systems Neuroscience, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
| | - Sofie Louise Valk
- Institute of Neuroscience and Medicine (INM-7: Brain and Behaviour), Research Centre Jülich, 52425, Jülich, Germany.
- Institute of Systems Neuroscience, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany.
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Schreiner T, Staudigl T. Electrophysiological signatures of memory reactivation in humans. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190293. [PMID: 32248789 PMCID: PMC7209925 DOI: 10.1098/rstb.2019.0293] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The reactivation of neural activity that was present during the encoding of an event is assumed to be essential for human episodic memory retrieval and the consolidation of memories during sleep. Pioneering animal work has already established a crucial role of memory reactivation to prepare and guide behaviour. Research in humans is now delineating the neural processes involved in memory reactivation during both wakefulness and sleep as well as their functional significance. Focusing on the electrophysiological signatures of memory reactivation in humans during both memory retrieval and sleep-related consolidation, this review provides an overview of the state of the art in the field. We outline recent advances, methodological developments and open questions and specifically highlight commonalities and differences in the neuronal signatures of memory reactivation during the states of wakefulness and sleep. This article is part of the Theo Murphy meeting issue ‘Memory reactivation: replaying events past, present and future’.
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Affiliation(s)
- Thomas Schreiner
- School of Psychology and Centre for Human Brain Health, University of Birmingham, Birmingham, UK.,Department of Psychology, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Tobias Staudigl
- Department of Psychology, Ludwig-Maximilians-University Munich, Munich, Germany
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Boutin A, Doyon J. A sleep spindle framework for motor memory consolidation. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190232. [PMID: 32248783 DOI: 10.1098/rstb.2019.0232] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Sleep spindle activity has repeatedly been found to contribute to brain plasticity and consolidation of both declarative and procedural memories. Here we propose a framework for motor memory consolidation that outlines the essential contribution of the hierarchical and multi-scale periodicity of spindle activity, as well as of the synchronization and interaction of brain oscillations during this sleep-dependent process. We posit that the clustering of sleep spindles in 'trains', together with the temporally organized alternation between spindles and associated refractory periods, is critical for efficient reprocessing and consolidation of motor memories. We further argue that the long-term retention of procedural memories relies on the synchronized (functional connectivity) local reprocessing of new information across segregated, but inter-connected brain regions that are involved in the initial learning process. Finally, we propose that oscillatory synchrony in the spindle frequency band may reflect the cross-structural reactivation, reorganization and consolidation of motor, and potentially declarative, memory traces within broader subcortical-cortical networks during sleep. This article is part of the Theo Murphy meeting issue 'Memory reactivation: replaying events past, present and future'.
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Affiliation(s)
- Arnaud Boutin
- Université Paris-Saclay, CIAMS, 91405, Orsay, France.,Université d'Orléans, CIAMS, 45067, Orléans, France
| | - Julien Doyon
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada.,Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Canada
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Horne J. REM sleep vs exploratory wakefulness: Alternatives within adult ‘sleep debt’? Sleep Med Rev 2020; 50:101252. [DOI: 10.1016/j.smrv.2019.101252] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 12/06/2019] [Accepted: 12/06/2019] [Indexed: 10/25/2022]
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Sleep Spindles Promote the Restructuring of Memory Representations in Ventromedial Prefrontal Cortex through Enhanced Hippocampal-Cortical Functional Connectivity. J Neurosci 2020; 40:1909-1919. [PMID: 31959699 DOI: 10.1523/jneurosci.1946-19.2020] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 01/06/2020] [Accepted: 01/08/2020] [Indexed: 11/21/2022] Open
Abstract
Memory consolidation is hypothesized to involve the distribution and restructuring of memory representations across hippocampal and cortical regions. Theories suggest that, through extended hippocampal-cortical interactions, cortical ensembles come to represent more integrated, or overlapping, memory traces that prioritize commonalities across related memories. Sleep processes, particularly fast sleep spindles, are thought to support consolidation, but evidence for this relationship has been mostly limited to memory retention benefits. Whether fast spindles provide a mechanism for neural changes hypothesized to support consolidation, including the strengthening of hippocampal-cortical networks and integration across memory representations, remains unclear, as does the specificity of regions involved. Using functional connectivity analyses of human fMRI data (both sexes), we show that fast spindle density during overnight sleep is related to enhanced hippocampal-cortical functional connectivity the next day, when restudying information learned before sleep. Spindle density modulated connectivity in distinct hippocampal-cortical networks depending on the category of the consolidated stimuli. Specifically, spindle density correlated with functional connectivity between anterior hippocampus and ventromedial prefrontal cortex (vmPFC) for object-word pairs, and posterior hippocampus and posteromedial cortex for scene-word pairs. Using multivariate pattern analyses, we also show that fast spindle density during postlearning sleep is associated with greater pattern similarity, or representational overlap, across individual object-word memories in vmPFC the next day. Further, the relationship between fast spindle density and representational overlap in vmPFC was mediated by the degree of anterior hippocampal-vmPFC functional connectivity. Together, these results suggest that fast spindles support the network distribution of memory traces, potentially restructuring memory representations in vmPFC.SIGNIFICANCE STATEMENT How new experiences are transformed into long-term memories remains a fundamental question for neuroscience research. Theories suggest that memories are stabilized as they are reorganized in the brain, a process thought to be supported by sleep oscillations, particularly sleep spindles. Although sleep spindles have been associated with benefits in memory retention, it is not well understood how spindles modify neural memory traces. This study found that spindles during overnight sleep correlate with changes in neural memory traces, including enhanced functional connectivity in distinct hippocampal-cortical networks and increased pattern similarity among memories in the cortex. The results provide critical evidence that spindles during overnight sleep may act as a physiological mechanism for the restructuring of neural memory traces.
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A Pilot Study on Sleep Quality, Forgiveness, Religion, Spirituality, and General Health of Women Living in a Homeless Mission. Holist Nurs Pract 2020; 34:49-56. [DOI: 10.1097/hnp.0000000000000362] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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