1
|
Joensen BH, Ashton JE, Berens SC, Gaskell MG, Horner AJ. An Enduring Role for Hippocampal Pattern Completion in Addition to an Emergent Nonhippocampal Contribution to Holistic Episodic Retrieval after a 24 h Delay. J Neurosci 2024; 44:e1740232024. [PMID: 38527810 PMCID: PMC11063816 DOI: 10.1523/jneurosci.1740-23.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 03/05/2024] [Accepted: 03/08/2024] [Indexed: 03/27/2024] Open
Abstract
Episodic memory retrieval is associated with the holistic neocortical reinstatement of all event information, an effect driven by hippocampal pattern completion. However, whether holistic reinstatement occurs, and whether hippocampal pattern completion continues to drive reinstatement, after a period of consolidation is unclear. Theories of systems consolidation predict either a time-variant or time-invariant role of the hippocampus in the holistic retrieval of episodic events. Here, we assessed whether episodic events continue to be reinstated holistically and whether hippocampal pattern completion continues to facilitate holistic reinstatement following a period of consolidation. Female and male human participants learned "events" that comprised multiple overlapping pairs of event elements (e.g., person-location, object-location, location-person). Importantly, encoding occurred either immediately before or 24 h before retrieval. Using fMRI during the retrieval of events, we show evidence for holistic reinstatement, as well as a correlation between reinstatement and hippocampal pattern completion, regardless of whether retrieval occurred immediately or 24 h after encoding. Thus, hippocampal pattern completion continues to contribute to holistic reinstatement after a delay. However, our results also revealed that some holistic reinstatement can occur without evidence for a corresponding signature of hippocampal pattern completion after a delay (but not immediately after encoding). We therefore show that hippocampal pattern completion, in addition to a nonhippocampal process, has a role in holistic reinstatement following a period of consolidation. Our results point to a consolidation process where the hippocampus and neocortex may work in an additive, rather than compensatory, manner to support episodic memory retrieval.
Collapse
Affiliation(s)
- Bárður H Joensen
- Department of Psychology, Lund University, Lund 221 00, Sweden
- Department of Psychology, University of York, York YO10 5DD, United Kingdom
| | - Jennifer E Ashton
- Department of Psychology, University of York, York YO10 5DD, United Kingdom
| | - Sam C Berens
- School of Psychology, University of Sussex, Falmer BN1 9QH, 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 5NG, United Kingdom
| | - Aidan J Horner
- Department of Psychology, University of York, York YO10 5DD, United Kingdom
- York Biomedical Research Institute, University of York, York YO10 5NG, United Kingdom
| |
Collapse
|
2
|
Cabrera Y, Koymans KJ, Poe GR, Kessels HW, Van Someren EJW, Wassing R. Overnight neuronal plasticity and adaptation to emotional distress. Nat Rev Neurosci 2024; 25:253-271. [PMID: 38443627 DOI: 10.1038/s41583-024-00799-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/01/2024] [Indexed: 03/07/2024]
Abstract
Expressions such as 'sleep on it' refer to the resolution of distressing experiences across a night of sound sleep. Sleep is an active state during which the brain reorganizes the synaptic connections that form memories. This Perspective proposes a model of how sleep modifies emotional memory traces. Sleep-dependent reorganization occurs through neurophysiological events in neurochemical contexts that determine the fates of synapses to grow, to survive or to be pruned. We discuss how low levels of acetylcholine during non-rapid eye movement sleep and low levels of noradrenaline during rapid eye movement sleep provide a unique window of opportunity for plasticity in neuronal representations of emotional memories that resolves the associated distress. We integrate sleep-facilitated adaptation over three levels: experience and behaviour, neuronal circuits, and synaptic events. The model generates testable hypotheses for how failed sleep-dependent adaptation to emotional distress is key to mental disorders, notably disorders of anxiety, depression and post-traumatic stress with the common aetiology of insomnia.
Collapse
Affiliation(s)
- Yesenia Cabrera
- Department of Integrative Biology and Physiology, Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA
| | - Karin J Koymans
- Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Gina R Poe
- Department of Integrative Biology and Physiology, Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA
| | - Helmut W Kessels
- Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
- Department of Synaptic Plasticity and Behaviour, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Society for Arts and Sciences, Amsterdam, Netherlands
| | - Eus J W Van Someren
- Department of Sleep and Cognition, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Society for Arts and Sciences, Amsterdam, Netherlands
- Department of Integrative Neurophysiology and Psychiatry, VU University, Amsterdam UMC, Amsterdam, Netherlands
- Center for Neurogenomics and Cognitive Research, VU University, Amsterdam UMC, Amsterdam, Netherlands
| | - Rick Wassing
- Sleep and Circadian Research, Woolcock Institute of Medical Research, Macquarie University, Sydney, New South Wales, Australia.
- School of Psychological Sciences, Faculty of Medicine Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia.
- Sydney Local Health District, Sydney, New South Wales, Australia.
| |
Collapse
|
3
|
Tallman CW, Luo Z, Smith CN. Human brain activity and functional connectivity associated with verbal long-term memory consolidation across 1 month. Front Hum Neurosci 2024; 18:1342552. [PMID: 38450223 PMCID: PMC10915245 DOI: 10.3389/fnhum.2024.1342552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 01/22/2024] [Indexed: 03/08/2024] Open
Abstract
Introduction Declarative memories are initially dependent on the hippocampus and become stabilized through the neural reorganization of connections between the medial temporal lobe and neocortex. The exact time-course of these neural changes is not well established, although time-dependent changes in retrieval-related brain function can be detected across relatively short time periods in humans (e.g., hours to months). Methods In a study involving older adults with normal cognition (N = 24), we investigated changes in brain activity and functional connectivity associated with the long-term memory consolidation of verbal material over one month. Participants studied fact-like, three-word sentences at 1-month, 1-week, 1-day, and 1-hour intervals before a recognition memory test inside an MRI scanner. Old/new recognition with confidence ratings and response times were recorded. We examined whole-brain changes in retrieval-related brain activity, as well as functional connectivity of the hippocampus and ventromedial prefrontal cortex (vmPFC), as memories aged from 1 hour to 1 month. Secondary analyses minimized the effect of confounding factors affected by memory age (i.e., changes in confidence and response time or re-encoding of targets). Results Memory accuracy, confidence ratings, and response times changed with memory age. A memory age network was identified where retrieval-related brain activity in cortical regions increased or decreased as a function of memory age. Hippocampal brain activity in an anatomical region of interest decreased with memory age. Importantly, these changes in retrieval-related activity were not confounded with changes in activity related to concomitant changes in behavior or encoding. Exploratory analyses of vmPFC functional connectivity as a function of memory age revealed increased connectivity with the posterior parietal cortex, as well as with the vmPFC itself. In contrast, hippocampal functional connectivity with the vmPFC and orbitofrontal cortex decreased with memory age. Discussion The observed changes in retrieval-related brain activity and functional connectivity align with the predictions of standard systems consolidation theory. These results suggest that processes consistent with long-term memory consolidation can be identified over short time periods using fMRI, particularly for verbal material.
Collapse
Affiliation(s)
- Catherine W. Tallman
- Department of Psychology, University of California, San Diego, San Diego, CA, United States
- Veterans Affairs San Diego Healthcare System, Department of Research Service, San Diego, CA, United States
| | - Zhishang Luo
- Veterans Affairs San Diego Healthcare System, Department of Research Service, San Diego, CA, United States
- Halıcıoğlu Data Science Institute, University of California, San Diego, San Diego, CA, United States
| | - Christine N. Smith
- Veterans Affairs San Diego Healthcare System, Department of Research Service, San Diego, CA, United States
- Department of Psychiatry, University of California, San Diego, San Diego, CA, United States
- Center for the Neurobiology of Learning and Memory, University of California, Irvine, Irvine, CA, United States
| |
Collapse
|
4
|
Hamel A, Mary A, Rauchs G. Sleep and memory consolidation in aging: A neuroimaging perspective. Rev Neurol (Paris) 2023; 179:658-666. [PMID: 37586942 DOI: 10.1016/j.neurol.2023.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 08/01/2023] [Accepted: 08/02/2023] [Indexed: 08/18/2023]
Abstract
Recently acquired information is strengthened and consolidated during sleep. For hippocampus-dependent memory, this process is assumed to occur mainly during slow wave sleep. Changes in sleep patterns in older adults can contribute to the disruption of the consolidation process during sleep and thus lead to cognitive impairment. Current findings suggest that reduced gray matter volume, particularly in frontal areas, Aβ and tau accumulation in combination with age-related changes of specific oscillations during sleep may contribute to memory deficits. This non-exhaustive review aims at providing a comprehensive picture of the associations between sleep changes and memory consolidation in aging, mainly based on neuroimaging studies. Overall, data confirm the utmost importance of sleep for healthy aging and the need to develop interventions aiming at improving sleep to reduce cognitive decline observed with advancing age.
Collapse
Affiliation(s)
- A Hamel
- Normandie Univ, UNICAEN, Inserm, U1237, PhIND "Physiopathology and Imaging of Neurological Disorders", Neuropresage Team, Institut Blood and Brain @ Caen-Normandie, Cyceron, Caen, France; UR2NF, Neuropsychology and Functional Neuroimaging Research Unit at CRCN, Center for Research in Cognition and Neurosciences and UNI, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - A Mary
- UR2NF, Neuropsychology and Functional Neuroimaging Research Unit at CRCN, Center for Research in Cognition and Neurosciences and UNI, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - G Rauchs
- Normandie Univ, UNICAEN, Inserm, U1237, PhIND "Physiopathology and Imaging of Neurological Disorders", Neuropresage Team, Institut Blood and Brain @ Caen-Normandie, Cyceron, Caen, France.
| |
Collapse
|
5
|
Krenz V, Alink A, Sommer T, Roozendaal B, Schwabe L. Time-dependent memory transformation in hippocampus and neocortex is semantic in nature. Nat Commun 2023; 14:6037. [PMID: 37758725 PMCID: PMC10533832 DOI: 10.1038/s41467-023-41648-1] [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: 07/06/2022] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
Memories undergo a time-dependent neural reorganization, which is assumed to be accompanied by a transformation from detailed to more gist-like memory. However, the nature of this transformation and its underlying neural mechanisms are largely unknown. Here, we report that the time-dependent transformation of memory is semantic in nature, while we find no credible evidence for a perceptual transformation. Model-based MRI analyses reveal time-dependent increases in semantically transformed representations of events in prefrontal and parietal cortices, while specific pattern representations in the anterior hippocampus decline over time. Posterior hippocampal memory reinstatement, in turn, increases over time and is linked to the semantic gist of the original memory, without a statistically significant link to perceptual details. These findings indicate that qualitative changes in memory over time, associated with distinct representational changes in the neocortex and within the hippocampus, reflect a semantic transformation, which may promote the integration of memories into abstract knowledge structures.
Collapse
Affiliation(s)
- Valentina Krenz
- Department of Cognitive Psychology, Institute of Psychology, Universität Hamburg, Von-Melle-Park 5, 20146, Hamburg, Germany
| | - Arjen Alink
- Department of General Psychology, Institute of Psychology, Universität Hamburg, Von-Melle-Park 11, 20146, Hamburg, Germany
- Department of Systems Neuroscience, University Medical Centre Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Tobias Sommer
- Department of Systems Neuroscience, University Medical Centre Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Benno Roozendaal
- Department of Cognitive Neuroscience, Radboud University Medical Center, 6500 HB, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Kapittelweg 29, 6525 EN, Nijmegen, The Netherlands
| | - Lars Schwabe
- Department of Cognitive Psychology, Institute of Psychology, Universität Hamburg, Von-Melle-Park 5, 20146, Hamburg, Germany.
| |
Collapse
|
6
|
Tambini A, Miller J, Ehlert L, Kiyonaga A, D’Esposito M. Structured memory representations develop at multiple time scales in hippocampal-cortical networks. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.06.535935. [PMID: 37066263 PMCID: PMC10104124 DOI: 10.1101/2023.04.06.535935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Influential views of systems memory consolidation posit that the hippocampus rapidly forms representations of specific events, while neocortical networks extract regularities across events, forming the basis of schemas and semantic knowledge. Neocortical extraction of schematic memory representations is thought to occur on a protracted timescale of months, especially for information that is unrelated to prior knowledge. However, this theorized evolution of memory representations across extended timescales, and differences in the temporal dynamics of consolidation across brain regions, lack reliable empirical support. To examine the temporal dynamics of memory representations, we repeatedly exposed human participants to structured information via sequences of fractals, while undergoing longitudinal fMRI for three months. Sequence-specific activation patterns emerged in the hippocampus during the first 1-2 weeks of learning, followed one week later by high-level visual cortex, and subsequently the medial prefrontal and parietal cortices. Schematic, sequence-general representations emerged in the prefrontal cortex after 3 weeks of learning, followed by the medial temporal lobe and anterior temporal cortex. Moreover, hippocampal and most neocortical representations showed sustained rather than time-limited dynamics, suggesting that representations tend to persist across learning. These results show that specific hippocampal representations emerge early, followed by both specific and schematic representations at a gradient of timescales across hippocampal-cortical networks as learning unfolds. Thus, memory representations do not exist only in specific brain regions at a given point in time, but are simultaneously present at multiple levels of abstraction across hippocampal-cortical networks.
Collapse
Affiliation(s)
- Arielle Tambini
- Center for Biomedical Imaging and Neuromodulation, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY
- Department of Psychiatry, New York University Grossman School of Medicine, New York, NY
| | - Jacob Miller
- Wu Tsai Institute, Department of Psychiatry, Yale University, New Haven, CT
| | - Luke Ehlert
- Department of Neurobiology and Behavior, University of California. Irvine, CA
| | - Anastasia Kiyonaga
- Department of Cognitive Science, University of California, San Diego, CA
| | - Mark D’Esposito
- Helen Wills Neuroscience Institute, University of California, Berkeley, CA
- Department of Psychology, University of California, Berkeley, CA
| |
Collapse
|
7
|
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.
Collapse
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
| |
Collapse
|
8
|
Whitney P, Kurinec CA, Hinson JM. Temporary amnesia from sleep loss: A framework for understanding consequences of sleep deprivation. Front Neurosci 2023; 17:1134757. [PMID: 37065907 PMCID: PMC10098076 DOI: 10.3389/fnins.2023.1134757] [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: 12/30/2022] [Accepted: 03/13/2023] [Indexed: 04/18/2023] Open
Abstract
Throughout its modern history, sleep research has been concerned with both the benefits of sleep and the deleterious impact of sleep disruption for cognition, behavior, and performance. When more specifically examining the impact of sleep on memory and learning, however, research has overwhelmingly focused on how sleep following learning facilitates memory, with less attention paid to how lack of sleep prior to learning can disrupt subsequent memory. Although this imbalance in research emphasis is being more frequently addressed by current investigators, there is a need for a more organized approach to examining the effect of sleep deprivation before learning. The present review briefly describes the generally accepted approach to analyzing effects of sleep deprivation on subsequent memory and learning by means of its effects on encoding. Then, we suggest an alternative framework with which to understand sleep loss and memory in terms of temporary amnesia from sleep loss (TASL). The review covers the well-characterized properties of amnesia arising from medial temporal lobe lesions and shows how the pattern of preserved and impaired aspects of memory in amnesia may also be appearing during sleep loss. The view of the TASL framework is that amnesia and the amnesia-like deficits observed during sleep deprivation not only affect memory processes but will also be apparent in cognitive processes that rely on those memory processes, such as decision-making. Adoption of the TASL framework encourages movement away from traditional explanations based on narrowly defined domains of memory functioning, such as encoding, and taking instead a more expansive view of how brain structures that support memory, such as the hippocampus, interact with higher structures, such as the prefrontal cortex, to produce complex cognition and behavioral performance, and how this interaction may be compromised by sleep disruption.
Collapse
Affiliation(s)
- Paul Whitney
- Department of Psychology, Washington State University, Pullman, WA, United States
- Sleep and Performance Research Center, Washington State University, Spokane, WA, United States
- *Correspondence: Paul Whitney,
| | - Courtney A. Kurinec
- Sleep and Performance Research Center, Washington State University, Spokane, WA, United States
- Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, United States
| | - John M. Hinson
- Department of Psychology, Washington State University, Pullman, WA, United States
- Sleep and Performance Research Center, Washington State University, Spokane, WA, United States
| |
Collapse
|
9
|
Toor B, van den Berg N, Ray LB, Fogel SM. Sleep spindles and slow waves are physiological markers for age-related changes in gray matter in brain regions supporting problem-solving skills. Learn Mem 2023; 30:12-24. [PMID: 36564151 PMCID: PMC9872192 DOI: 10.1101/lm.053649.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 11/29/2022] [Indexed: 12/25/2022]
Abstract
As we age, the added benefit of sleep for memory consolidation is lost. One of the hallmark age-related changes in sleep is the reduction of sleep spindles and slow waves. Gray matter neurodegeneration is related to both age-related changes in sleep and age-related changes in memory, including memory for problem-solving skills. Here, we investigated whether spindles and slow waves might serve as biological markers for neurodegeneration of gray matter and for the related memory consolidation deficits in older adults. Forty healthy young adults (20-35 yr) and 30 healthy older adults (60-85 yr) were assigned to either nap or wake conditions. Participants were trained on the Tower of Hanoi in the morning, followed by either a 90-min nap opportunity or period of wakefulness, and were retested afterward. We found that age-related changes in sleep spindles and slow waves were differentially related to gray matter intensity in young and older adults in brain regions that support sleep-dependent memory consolidation for problem-solving skills. Specifically, we found that spindles were related to gray matter in neocortical areas (e.g., somatosensory and parietal cortex), and slow waves were related to gray matter in the anterior cingulate, hippocampus, and caudate, all areas known to support problem-solving skills. These results suggest that both sleep spindles and slow waves may serve as biological markers of age-related neurodegeneration of gray matter and the associated reduced benefit of sleep for memory consolidation in older adults.
Collapse
Affiliation(s)
- Balmeet Toor
- School of Psychology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | | | - Laura B Ray
- School of Psychology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Stuart M Fogel
- School of Psychology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
- Sleep Unit, The Royal's Institute of Mental Health Research, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
- University of Ottawa Brain and Mind Institute, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| |
Collapse
|
10
|
Talamini LM, van Moorselaar D, Bakker R, Bulath M, Szegedi S, Sinichi M, De Boer M. No evidence for a preferential role of sleep in episodic memory abstraction. Front Neurosci 2022; 16:871188. [PMID: 36570837 PMCID: PMC9780604 DOI: 10.3389/fnins.2022.871188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 11/21/2022] [Indexed: 12/13/2022] Open
Abstract
Substantial evidence suggests that sleep has a role in declarative memory consolidation. An influential notion holds that such sleep-related memory consolidation is associated with a process of abstraction. The neural underpinnings of this putative process are thought to involve a hippocampo-neocortical dialogue. Specifically, the idea is that, during sleep, the statistical contingencies across episodes are re-coded to a less hippocampus-dependent format, while at the same time losing configural information. Two previous studies from our lab, however, failed to show a preferential role of sleep in either episodic memory decontextualisation or the formation of abstract knowledge across episodic exemplars. Rather these processes occurred over sleep and wake time alike. Here, we present two experiments that replicate and extend these previous studies and exclude some alternative interpretations. The combined data show that sleep has no preferential function in this respect. Rather, hippocampus-dependent memories are generalised to an equal extent across both wake and sleep time. The one point on which sleep outperforms wake is actually the preservation of episodic detail of memories stored prior to sleep.
Collapse
Affiliation(s)
- Lucia M. Talamini
- Brain and Cognition, Department of Psychology, University of Amsterdam, Amsterdam, Netherlands
- University of Amsterdam—Amsterdam Brain and Cognition, Amsterdam, Netherlands
| | - Dirk van Moorselaar
- Brain and Cognition, Department of Psychology, University of Amsterdam, Amsterdam, Netherlands
| | - Richard Bakker
- Brain and Cognition, Department of Psychology, University of Amsterdam, Amsterdam, Netherlands
| | - Máté Bulath
- Brain and Cognition, Department of Psychology, University of Amsterdam, Amsterdam, Netherlands
| | - Steffie Szegedi
- Brain and Cognition, Department of Psychology, University of Amsterdam, Amsterdam, Netherlands
| | - Mohammadamin Sinichi
- Brain and Cognition, Department of Psychology, University of Amsterdam, Amsterdam, Netherlands
| | - Marieke De Boer
- Brain and Cognition, Department of Psychology, University of Amsterdam, Amsterdam, Netherlands
- University of Amsterdam—Amsterdam Brain and Cognition, Amsterdam, Netherlands
| |
Collapse
|
11
|
Siestrup S, Jainta B, Cheng S, Schubotz RI. Solidity Meets Surprise: Cerebral and Behavioral Effects of Learning from Episodic Prediction Errors. J Cogn Neurosci 2022; 35:1-23. [PMID: 36473102 DOI: 10.1162/jocn_a_01948] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
How susceptible a memory is to later modification might depend on how stable the episode has been encoded. This stability was proposed to increase when retrieving information more (vs. less) often and in a spaced (vs. massed) practice. Using fMRI, we examined the effects of these different pre-fMRI retrieval protocols on the subsequent propensity to learn from episodic prediction errors. After encoding a set of different action stories, participants came back for two pre-fMRI retrieval sessions in which they encountered original episodes either 2 or 8 times in either a spaced or a massed retrieval protocol. One week later, we cued episodic retrieval during the fMRI session by using original or modified videos of encoded action stories. Recurrent experience of modified episodes was associated with increasing activity in the episodic memory network including hippocampal and cortical areas, when leading to false memories in a post-fMRI memory test. While this observation clearly demonstrated learning from episodic prediction errors, we found no evidence for a modulatory effect of the different retrieval protocols. As expected, the benefit of retrieving an episode more often was reflected in better memory for originally encoded episodes. In addition, frontal activity increased for episodic prediction errors when episodes had been less frequently retrieved pre-fMRI. A history of spaced versus massed retrieval was associated with increased activation throughout the episodic memory network, with no significant effect on behavioral performance. Our findings show that episodic prediction errors led to false memories. The history of different retrieval protocols was reflected in memory performance and brain responses to episodic prediction errors, but did not interact with the brain's episodic learning response.
Collapse
|
12
|
Iggena D, Maier PM, Häußler SM, Menk M, Olze H, Larkum ME, Finke C, Ploner CJ. Post-encoding modulation of spatial memory consolidation by propofol. Cortex 2022; 156:1-12. [DOI: 10.1016/j.cortex.2022.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 05/09/2022] [Accepted: 08/10/2022] [Indexed: 11/03/2022]
|
13
|
García-Pérez MA, Irani M, Tiznado V, Bustamante T, Inostroza M, Maldonado PE, Valdés JL. Cortico-Hippocampal Oscillations Are Associated With the Developmental Onset of Hippocampal-Dependent Memory. Front Neurosci 2022; 16:891523. [PMID: 35812209 PMCID: PMC9260104 DOI: 10.3389/fnins.2022.891523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/31/2022] [Indexed: 11/13/2022] Open
Abstract
Hippocampal-dependent memories emerge late during postnatal development, aligning with hippocampal maturation. During sleep, the two-stage memory formation model states that through hippocampal-neocortical interactions, cortical slow-oscillations (SO), thalamocortical Spindles, and hippocampal sharp-wave ripples (SWR) are synchronized, allowing for the consolidation of hippocampal-dependent memories. However, evidence supporting this hypothesis during development is still lacking. Therefore, we performed successive object-in-place tests during a window of memory emergence and recorded in vivo the occurrence of SO, Spindles, and SWR during sleep, immediately after the memory encoding stage of the task. We found that hippocampal-dependent memory emerges at the end of the 4th postnatal week independently of task overtraining. Furthermore, we observed that those animals with better performance in the memory task had increased Spindle density and duration and lower density of SWR. Moreover, we observed changes in the SO-Spindle and Spindle-SWR temporal-coupling during this developmental period. Our results provide new evidence for the onset of hippocampal-dependent memory and its relationship to the oscillatory phenomenon occurring during sleep that helps us understand how memory consolidation models fit into the early stages of postnatal development.
Collapse
Affiliation(s)
- María A. García-Pérez
- Departamento de Neurociencia, Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Departamento de Psiquiatría, Centro Interdisciplinario de Neurociencias UC, Pontificia Universidad Católica de Chile, Santiago, Chile
- Biomedical Neuroscience Institute (BNI), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Martin Irani
- Departamento de Psiquiatría, Centro Interdisciplinario de Neurociencias UC, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Vicente Tiznado
- Departamento de Psiquiatría, Centro Interdisciplinario de Neurociencias UC, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Tamara Bustamante
- Departamento de Neurociencia, Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Biomedical Neuroscience Institute (BNI), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Marion Inostroza
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | - Pedro E. Maldonado
- Departamento de Neurociencia, Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Biomedical Neuroscience Institute (BNI), Facultad de Medicina, Universidad de Chile, Santiago, Chile
- National Center for Artificial Intelligence, CENIA, Santiago, Chile
| | - José L. Valdés
- Departamento de Neurociencia, Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Biomedical Neuroscience Institute (BNI), Facultad de Medicina, Universidad de Chile, Santiago, Chile
- *Correspondence: José L. Valdés,
| |
Collapse
|
14
|
Milinski L, Nodal FR, Vyazovskiy VV, Bajo VM. Tinnitus: at a crossroad between phantom perception and sleep. Brain Commun 2022; 4:fcac089. [PMID: 35620170 PMCID: PMC9128384 DOI: 10.1093/braincomms/fcac089] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 12/31/2021] [Accepted: 03/31/2022] [Indexed: 11/25/2022] Open
Abstract
Sensory disconnection from the environment is a hallmark of sleep and is crucial
for sleep maintenance. It remains unclear, however, whether internally generated
percepts—phantom percepts—may overcome such disconnection and, in
turn, how sleep and its effect on sensory processing and brain plasticity may
affect the function of the specific neural networks underlying such phenomena. A
major hurdle in addressing this relationship is the methodological difficulty to
study sensory phantoms, due to their subjective nature and lack of control over
the parameters or neural activity underlying that percept. Here, we explore the
most prevalent phantom percept, subjective tinnitus—or tinnitus for
short—as a model to investigate this. Tinnitus is the permanent
perception of a sound with no identifiable corresponding acoustic source. This
review offers a novel perspective on the functional interaction between brain
activity across the sleep–wake cycle and tinnitus. We discuss
characteristic features of brain activity during tinnitus in the awake and the
sleeping brain and explore its effect on sleep functions and homeostasis. We ask
whether local changes in cortical activity in tinnitus may overcome sensory
disconnection and prevent the occurrence of global restorative sleep and, in
turn, how accumulating sleep pressure may temporarily alleviate the persistence
of a phantom sound. Beyond an acute interaction between sleep and neural
activity, we discuss how the effects of sleep on brain plasticity may contribute
to aberrant neural circuit activity and promote tinnitus consolidation. Tinnitus
represents a unique window into understanding the role of sleep in sensory
processing. Clarification of the underlying relationship may offer novel
insights into therapeutic interventions in tinnitus management.
Collapse
Affiliation(s)
- Linus Milinski
- University of Oxford, Department of Physiology, Anatomy and Genetics, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Fernando R. Nodal
- University of Oxford, Department of Physiology, Anatomy and Genetics, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Vladyslav V. Vyazovskiy
- University of Oxford, Department of Physiology, Anatomy and Genetics, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Victoria M. Bajo
- University of Oxford, Department of Physiology, Anatomy and Genetics, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| |
Collapse
|
15
|
Toor B, van den Berg NH, Fang Z, Pozzobon A, Ray LB, Fogel SM. Age-related differences in problem-solving skills: Reduced benefit of sleep for memory trace consolidation. Neurobiol Aging 2022; 116:55-66. [DOI: 10.1016/j.neurobiolaging.2022.04.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 04/05/2022] [Accepted: 04/17/2022] [Indexed: 10/18/2022]
|
16
|
Retrieval suppression induced forgetting on 1-week-old consolidated episodic memories. Psychon Bull Rev 2022; 29:1377-1386. [PMID: 35357668 DOI: 10.3758/s13423-022-02096-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2022] [Indexed: 11/08/2022]
Abstract
Retrieval suppression has been established to cause forgetting on a wide range of memory types, but mostly in newly formed memories. Over time, the consolidation process stabilizes memory and changes the memory locus in the brain, which may affect the effectiveness of retrieval suppression. In two experiments, we examined whether retrieval suppression can induce forgetting on consolidated episodic memories and explored its potential reliance on explicit memory reactivation or spontaneous memory intrusions to destabilize the consolidated memory. We found that, compared with associative interference, another well-established forgetting approach, retrieval suppression consistently induced forgetting on 1-week-old memories. This suppression-induced forgetting was uncovered stably via an independent retrieval cue, suggesting its effect being on the target memory itself. However, we did not find evidence of modulation on the suppression-induced forgetting by either explicit reactivation or spontaneous intrusions. Together, our results extend the suppression-induced forgetting to episodic memories that have been consolidated for 1 week and suggest that retrieval suppression could destabilize consolidated memories.
Collapse
|
17
|
Examining the relationship between working memory consolidation and long-term consolidation. Psychon Bull Rev 2022; 29:1625-1648. [PMID: 35357669 DOI: 10.3758/s13423-022-02084-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/04/2022] [Indexed: 11/08/2022]
Abstract
An emerging area of research is focused on the relationship between working memory and long-term memory and the likely overlap between these processes. Of particular interest is how some information first maintained in working memory is retained for longer periods and eventually preserved in long-term memory. The process of stabilizing transient memory representations for lasting retention is referred to as consolidation in both the working memory and long-term memory literature, although these have historically been viewed as independent constructs. The present review aims to investigate the relationship between working memory consolidation and long-term memory consolidation, which both have rich, but distinct, histories. This review provides an overview of the proposed models and neural mechanisms of both types of consolidation, as well as clinical findings related to consolidation and potential approaches for the manipulation of consolidation. Finally, two hypotheses are proposed to explain the relationship between working memory consolidation and long-term memory consolidation.
Collapse
|
18
|
Tallman CW, Clark RE, Smith CN. Human brain activity and functional connectivity as memories age from one hour to one month. Cogn Neurosci 2022; 13:115-133. [DOI: 10.1080/17588928.2021.2021164] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Catherine W. Tallman
- Department of Psychology, UCSD, San Diego, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
| | - Robert E. Clark
- Department of Psychiatry, UCSD, San Diego, CA, USA
- Center for the Neurobiology of Learning and Memory, UCI, San Diego, CA, USA
| | - Christine N. Smith
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
- Department of Psychiatry, UCSD, San Diego, CA, USA
- Center for the Neurobiology of Learning and Memory, UCI, San Diego, CA, USA
| |
Collapse
|
19
|
Krenz V, Sommer T, Alink A, Roozendaal B, Schwabe L. Noradrenergic arousal after encoding reverses the course of systems consolidation in humans. Nat Commun 2021; 12:6054. [PMID: 34663784 PMCID: PMC8523710 DOI: 10.1038/s41467-021-26250-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 09/21/2021] [Indexed: 11/23/2022] Open
Abstract
It is commonly assumed that episodic memories undergo a time-dependent systems consolidation process, during which hippocampus-dependent memories eventually become reliant on neocortical areas. Here we show that systems consolidation dynamics can be experimentally manipulated and even reversed. We combined a single pharmacological elevation of post-encoding noradrenergic activity through the α2-adrenoceptor antagonist yohimbine with fMRI scanning both during encoding and recognition testing either 1 or 28 days later. We show that yohimbine administration, in contrast to placebo, leads to a time-dependent increase in hippocampal activity and multivariate encoding-retrieval pattern similarity, an indicator of episodic reinstatement, between 1 and 28 days. This is accompanied by a time-dependent decrease in neocortical activity. Behaviorally, these neural changes are linked to a reduced memory decline over time after yohimbine intake. These findings indicate that noradrenergic activity shortly after encoding may alter and even reverse systems consolidation in humans, thus maintaining vividness of memories over time.
Collapse
Affiliation(s)
- Valentina Krenz
- Department of Cognitive Psychology, Institute of Psychology, Universität Hamburg, Von-Melle-Park 5, 20146, Hamburg, Germany
| | - Tobias Sommer
- University Medical Centre Hamburg-Eppendorf, Department of Systems Neuroscience, Martinistraße 52, 20246, Hamburg, Germany
| | - Arjen Alink
- University Medical Centre Hamburg-Eppendorf, Department of Systems Neuroscience, Martinistraße 52, 20246, Hamburg, Germany
| | - Benno Roozendaal
- Department of Cognitive Neuroscience, Radboud University Medical Center, 6500 HB, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Kapittelweg 29, 6525 EN, Nijmegen, The Netherlands
| | - Lars Schwabe
- Department of Cognitive Psychology, Institute of Psychology, Universität Hamburg, Von-Melle-Park 5, 20146, Hamburg, Germany.
| |
Collapse
|
20
|
Baena D, Cantero JL, Atienza M. Stability of neural encoding moderates the contribution of sleep and repeated testing to memory consolidation. Neurobiol Learn Mem 2021; 185:107529. [PMID: 34597816 DOI: 10.1016/j.nlm.2021.107529] [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: 05/03/2021] [Revised: 09/03/2021] [Accepted: 09/24/2021] [Indexed: 10/20/2022]
Abstract
There is evidence suggesting that online consolidation during retrieval-mediated learning interacts with offline consolidation during subsequent sleep to transform memory. Here we investigate whether this interaction persists when retrieval-mediated learning follows post-training sleep and whether the direction of this interaction is conditioned by the quality of encoding resulting from manipulation of the amount of sleep on the previous night. The quality of encoding was determined by computing the degree of similarity between EEG-activity patterns across restudy of face pairs in two groups of young participants, one who slept the last 4 h of the pre-training night, and another who slept 8 h. The offline consolidation was assessed by computing the degree of coupling between slow oscillations (SOs) and spindles (SPs) during post-training sleep, while the online consolidation was evaluated by determining the degree of similarity between EEG-activity patterns recorded during the study phase and during repeated recognition of either the same face pair (i.e., specific similarity) or face pairs sharing sex and profession (i.e., categorical similarity) to evaluate differentiation and generalization, respectively. The study and recognition phases were separated by a night of normal sleep duration. Mixed-effects models revealed that the stability of neural encoding moderated the relationship between sleep- and retrieval-mediated consolidation processes over left frontal regions. For memories showing lower encoding stability, the enhanced SO-SP coupling was associated with increased reinstatement of category-specific encoding-related activity at the expense of content-specific activity, whilst the opposite occurred for memories showing greater encoding stability. Overall, these results suggest that offline consolidation during post-training sleep interacts with online consolidation during retrieval the next day to favor the reorganization of memory contents, by increasing specificity of stronger memories and generalization of the weaker ones.
Collapse
Affiliation(s)
- Daniel Baena
- Laboratory of Functional Neuroscience, Universidad Pablo de Olavide, Seville 41013, Spain
| | - Jose L Cantero
- Laboratory of Functional Neuroscience, Universidad Pablo de Olavide, Seville 41013, Spain; CIBERNED, Network Center for Biomedical Research in Neurodegenerative Diseases, Spain
| | - Mercedes Atienza
- Laboratory of Functional Neuroscience, Universidad Pablo de Olavide, Seville 41013, Spain; CIBERNED, Network Center for Biomedical Research in Neurodegenerative Diseases, Spain.
| |
Collapse
|
21
|
Cowan ET, Liu AA, Henin S, Kothare S, Devinsky O, Davachi L. Time-dependent transformations of memory representations differ along the long axis of the hippocampus. Learn Mem 2021; 28:329-340. [PMID: 34400534 PMCID: PMC8372564 DOI: 10.1101/lm.053438.121] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 07/09/2021] [Indexed: 11/24/2022]
Abstract
Research has shown that sleep is beneficial for the long-term retention of memories. According to theories of memory consolidation, memories are gradually reorganized, becoming supported by widespread, distributed cortical networks, particularly during postencoding periods of sleep. However, the effects of sleep on the organization of memories in the hippocampus itself remains less clear. In a 3-d study, participants encoded separate lists of word-image pairs differing in their opportunity for sleep-dependent consolidation. Pairs were initially studied either before or after an overnight sleep period, and were then restudied in a functional magnetic resonance imaging (fMRI) scan session. We used multivariate pattern similarity analyses to examine fine-grained effects of consolidation on memory representations in the hippocampus. We provide evidence for a dissociation along the long axis of the hippocampus that emerges with consolidation, such that representational patterns for object-word memories initially formed prior to sleep become differentiated in anterior hippocampus and more similar, or overlapping, in posterior hippocampus. Differentiation in anterior hippocampal representations correlated with subsequent behavioral performance. Furthermore, representational overlap in posterior hippocampus correlated with the duration of intervening slow wave sleep. Together, these results demonstrate that sleep-dependent consolidation promotes the reorganization of memory traces along the long axis of the hippocampus.
Collapse
Affiliation(s)
- Emily T Cowan
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - Anli A Liu
- Comprehensive Epilepsy Center, New York University, New York, New York 10016, USA
- Department of Neurology, New York University Langone Health, New York, New York 10017, USA
| | - Simon Henin
- Comprehensive Epilepsy Center, New York University, New York, New York 10016, USA
- Department of Neurology, New York University Langone Health, New York, New York 10017, USA
| | - Sanjeev Kothare
- Comprehensive Epilepsy Center, New York University, New York, New York 10016, USA
- Department of Neurology, New York University Langone Health, New York, New York 10017, USA
| | - Orrin Devinsky
- Comprehensive Epilepsy Center, New York University, New York, New York 10016, USA
- Department of Neurology, New York University Langone Health, New York, New York 10017, USA
| | - Lila Davachi
- Psychology Department, Columbia University, New York, New York 10027, USA
- Nathan Kline Institute, Orangeburg, New York 10962, USA
| |
Collapse
|
22
|
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.
Collapse
|
23
|
Farhadian N, Khazaie H, Nami M, Khazaie S. The role of daytime napping in declarative memory performance: a systematic review. Sleep Med 2021; 84:134-141. [PMID: 34148000 DOI: 10.1016/j.sleep.2021.05.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 04/25/2021] [Accepted: 05/20/2021] [Indexed: 10/21/2022]
Abstract
Sleep plays an important role in stabilizing and reinforcing memory of newly acquired information. Like nocturnal sleep, a daytime nap is shown to effectively contribute to memory processing. However, studies are often focused on nocturnal sleep. This review has aimed at systematically compiling the results of studies which have examined the effects of napping on declarative memory performance in healthy adults. Such studies have focused on different aspects of memory reinforcement following a diurnal nap including the involved mechanisms in memory reconsolidation, type of declarative tasks, cross-gender differences, the role of age, duration of nap and its delayed onset. One of the reviewed studies reported that even as short as 6 min of napping exerts a positive effect on memory function. Evidence from these studies indicates hippocampal-dependent enhancement of the learned information. Diurnal naps predominantly include non-rapid eye movement sleep with slow waves yielding potential effects on declarative memory. Evidence has shown that the empowered learning and retrieval depends upon spindle density during the nap. Moreover, the role of coordinated autonomic and central events in enhancing declarative memory has also been reported. Slow waves and sleep spindles are known to fuel declarative memory function during the NREM-2 (N2) stage of sleep.
Collapse
Affiliation(s)
- Negin Farhadian
- Substance Abuse Prevention Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran; Sleep Disorders Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Habibolah Khazaie
- Sleep Disorders Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Mohammad Nami
- Department of Neuroscience, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran; Neuroscience Center, INDICASAT, Panama City, Republic of Panama; Society for Brain Mapping and Therapeutics and Brain Mapping Foundation, Los Angeles, CA, USA
| | - Sepideh Khazaie
- Sleep Disorders Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran; Student Research Committee, University of Medical Sciences, Kermanshah, Iran.
| |
Collapse
|
24
|
Lifanov J, Linde-Domingo J, Wimber M. Feature-specific reaction times reveal a semanticisation of memories over time and with repeated remembering. Nat Commun 2021; 12:3177. [PMID: 34039970 PMCID: PMC8155072 DOI: 10.1038/s41467-021-23288-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 04/07/2021] [Indexed: 11/24/2022] Open
Abstract
Memories are thought to undergo an episodic-to-semantic transformation in the course of their consolidation. We here test if repeated recall induces a similar semanticisation, and if the resulting qualitative changes in memories can be measured using simple feature-specific reaction time probes. Participants studied associations between verbs and object images, and then repeatedly recalled the objects when cued with the verb, immediately and after a two-day delay. Reaction times during immediate recall demonstrate that conceptual features are accessed faster than perceptual features. Consistent with a semanticisation process, this perceptual-conceptual gap significantly increases across the delay. A significantly smaller perceptual-conceptual gap is found in the delayed recall data of a control group who repeatedly studied the verb-object pairings on the first day, instead of actively recalling them. Our findings suggest that wake recall and offline consolidation interact to transform memories over time, strengthening meaningful semantic information over perceptual detail.
Collapse
Affiliation(s)
- Julia Lifanov
- School of Psychology and Centre for Human Brain Health (CHBH), University of Birmingham, Edgbaston, Birmingham, UK.
| | - Juan Linde-Domingo
- Center for Adaptive Rationality, Max Planck Institute for Human Development, Berlin, Germany
| | - Maria Wimber
- School of Psychology and Centre for Human Brain Health (CHBH), University of Birmingham, Edgbaston, Birmingham, UK.
- Institute of Neuroscience & Psychology and Centre for Cognitive Neuroimaging (CCNi), University of Glasgow, Glasgow, UK.
| |
Collapse
|
25
|
Benear SL, Ngo CT, Olson IR, Newcombe NS. Understanding relational binding in early childhood: Interacting effects of overlap and delay. J Exp Child Psychol 2021; 208:105152. [PMID: 33895601 DOI: 10.1016/j.jecp.2021.105152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/05/2021] [Accepted: 03/11/2021] [Indexed: 10/21/2022]
Abstract
Episodic memories typically share overlapping elements in distinctive combinations, and to be valuable for future behavior they need to withstand delays. There is relatively little work on whether children have special difficulty with overlap or withstanding delay. However, Yim, Dennis, and Sloutsky (Psychological Science, 2013, Vol. 24, pp. 2163-2172) suggested that extensive overlap is more problematic for younger children, and Darby and Sloutsky (Psychological Science, 2015, Vol. 26, pp. 1937-1946) reported that a 48-h delay period actually improves children's memory for overlapping pairs of items. In the current study, we asked how children's episodic memory is affected by stimulus overlap, delay, and age using visual stimuli containing either overlapping or unique item pairs. Children aged 4 and 6 years were tested both immediately and after a 24-h delay. As expected, older children performed better than younger children, and both age groups performed worse on overlapping pairs. Surprisingly, the 24-h delay had only a marginal effect on overall accuracy. Although there were no interactions, when errors were examined, there was evidence that delay buffered memory for overlapping pairs against cross-contextual confusion for younger children.
Collapse
Affiliation(s)
- Susan L Benear
- Department of Psychology, Temple University, Philadelphia, PA 19122, USA.
| | - Chi T Ngo
- Center for Lifespan Psychology, Max Planck Institute for Human Development, 14195 Berlin, Germany
| | - Ingrid R Olson
- Department of Psychology, Temple University, Philadelphia, PA 19122, USA
| | - Nora S Newcombe
- Department of Psychology, Temple University, Philadelphia, PA 19122, USA
| |
Collapse
|
26
|
Durrant SJ, Johnson JM. Sleep’s Role in Schema Learning and Creative Insights. CURRENT SLEEP MEDICINE REPORTS 2021. [DOI: 10.1007/s40675-021-00202-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Abstract
Purpose of Review
A recent resurgence of interest in schema theory has influenced research on sleep-dependent memory consolidation and led to a new understanding of how schemata might be activated during sleep and play a role in the reorganisation of memories. This review is aimed at synthesising recent findings into a coherent narrative and draw overall conclusions.
Recent Findings
Rapid consolidation of schematic memories has been shown to benefit from an interval containing sleep. These memories have shown reduced reliance on the hippocampus following consolidation in both humans and rodents. Using a variety of methodologies, notably including the DRM paradigm, it has been shown that activation of a schema can increase the rate of false memory as a result of activation of semantic associates during slow wave sleep (SWS). Memories making use of a schema have shown increased activity in the medial prefrontal cortex, which may reflect both the schematic activation itself and a cognitive control component selecting an appropriate schema to use. SWS seems to be involved in assimilation of new memories within existing semantic frameworks and in making memories more explicit, while REM sleep may be more associated with creating entirely novel associations while keeping memories implicit.
Summary
Sleep plays an important role in schematic memory consolidation, with more rapid consolidation, reduced hippocampal involvement, and increased prefrontal involvement as the key characteristics. Both SWS and REM sleep may have a role to play.
Collapse
|
27
|
Miendlarzewska EA, Aberg KC, Bavelier D, Schwartz S. Prior Reward Conditioning Dampens Hippocampal and Striatal Responses during an Associative Memory Task. J Cogn Neurosci 2020; 33:402-421. [PMID: 33326326 DOI: 10.1162/jocn_a_01660] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Offering reward during encoding typically leads to better memory [Adcock, R. A., Thangavel, A., Whitfield-Gabrieli, S.,Knutson, B., & Gabrieli, J. D. E. Reward-motivated learning: Mesolimbic activation precedes memory formation. Neuron, 50, 507-517, 2006]. Whether such memory benefit persists when tested in a different task context remains, however, largely understudied [Wimmer, G. E., & Buechel, C. Reactivation of reward-related patterns from single past episodes supports memory-based decision making. Journal of Neuroscience, 36, 2868-2880, 2016]. Here, we ask whether reward at encoding leads to a generalized advantage across learning episodes, a question of high importance for any everyday life applications, from education to patient rehabilitation. Although we confirmed that offering monetary reward increased responses in the ventral striatum and pleasantness judgments for pictures used as stimuli, this immediate beneficial effect of reward did not carry over to a subsequent and different picture-location association memory task during which no reward was delivered. If anything, a trend for impaired memory accuracy was observed for the initially high-rewarded pictures as compared to low-rewarded ones. In line with this trend in behavioral performance, fMRI activity in reward (i.e., ventral striatum) and in memory (i.e., hippocampus) circuits was reduced during the encoding of new associations using previously highly rewarded pictures (compared to low-reward pictures). These neural effects extended to new pictures from same, previously highly rewarded semantic category. Twenty-four hours later, delayed recall of associations involving originally highly rewarded items was accompanied by decreased functional connectivity between the hippocampus and two brain regions implicated in value-based learning, the ventral striatum and the ventromedial PFC. We conclude that acquired reward value elicits a downward value-adjustment signal in the human reward circuit when reactivated in a novel nonrewarded context, with a parallel disengagement of memory-reward (hippocampal-striatal) networks, likely to undermine new associative learning. Although reward is known to promote learning, here we show how it may subsequently hinder hippocampal and striatal responses during new associative memory formation.
Collapse
Affiliation(s)
- Ewa A Miendlarzewska
- University of Geneva.,Campus Biotech, Geneva, Switzerland.,Montpellier Business School
| | | | | | | |
Collapse
|
28
|
Liu W, Kohn N, Fernández G. Probing the neural dynamics of mnemonic representations after the initial consolidation. Neuroimage 2020; 221:117213. [PMID: 32739553 DOI: 10.1016/j.neuroimage.2020.117213] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 07/22/2020] [Accepted: 07/26/2020] [Indexed: 12/22/2022] Open
Abstract
Memories are not stored as static engrams, but as dynamic representations affected by processes occurring after initial encoding. Previous studies revealed changes in activity and mnemonic representations in visual processing areas, parietal lobe, and hippocampus underlying repeated retrieval and suppression. However, these neural changes are usually induced by memory modulation immediately after memory formation. Here, we investigated 27 healthy participants with a two-day functional Magnetic Resonance Imaging study design to probe how established memories are dynamically modulated by retrieval and suppression 24 h after learning. Behaviorally, we demonstrated that established memories can still be strengthened by repeated retrieval. By contrast, repeated suppression had a modest negative effect, and suppression-induced forgetting was associated with individual suppression efficacy. Neurally, we demonstrated item-specific pattern reinstatements in visual processing areas, parietal lobe, and hippocampus. Then, we showed that repeated retrieval reduced activity amplitude in the ventral visual cortex and hippocampus, but enhanced the distinctiveness of activity patterns in the ventral visual cortex and parietal lobe. Critically, reduced activity was associated with enhanced representation of idiosyncratic memory traces in the ventral visual cortex and precuneus. In contrast, repeated memory suppression was associated with reduced lateral prefrontal activity, but relative intact mnemonic representations. Our results replicated most of the neural changes induced by memory retrieval and suppression immediately after learning and extended those findings to established memories after initial consolidation. Active retrieval seems to promote episode-unique mnemonic representations in the neocortex after initial encoding but also consolidation.
Collapse
Affiliation(s)
- Wei Liu
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, the Netherlands.
| | - Nils Kohn
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, the Netherlands
| | - Guillén Fernández
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, the Netherlands
| |
Collapse
|
29
|
Neural pattern similarity across concept exemplars predicts memory after a long delay. Neuroimage 2020; 219:117030. [PMID: 32526388 DOI: 10.1016/j.neuroimage.2020.117030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/14/2020] [Accepted: 06/05/2020] [Indexed: 11/21/2022] Open
Abstract
The irregularities of the world ensure that each interaction we have with a concept is unique. In order to generalize across these unique encounters to form a high-level representation of a concept, we must draw on similarities between exemplars to form new conceptual knowledge that is maintained over a long time. Two neural similarity measures - pattern robustness and encoding-retrieval similarity - are particularly important for predicting memory outcomes. In this study, we used fMRI to measure activity patterns while people encoded and retrieved novel pairings between unfamiliar (Dutch) words and visually presented animal species. We address two underexplored questions: 1) whether neural similarity measures can predict memory outcomes, despite perceptual variability between presentations of a concept and 2) if pattern similarity measures can predict subsequent memory over a long delay (i.e., one month). Our findings indicate that pattern robustness during encoding in brain regions that include parietal and medial temporal areas is an important predictor of subsequent memory. In addition, we found significant encoding-retrieval similarity in the left ventrolateral prefrontal cortex after a month's delay. These findings demonstrate that pattern similarity is an important predictor of memory for novel word-animal pairings even when the concept includes multiple exemplars. Importantly, we show that established predictive relationships between pattern similarity and subsequent memory do not require visually identical stimuli (i.e., are not simply due to low-level visual overlap between stimulus presentations) and are maintained over a month.
Collapse
|
30
|
Van Someren EJW. Brain mechanisms of insomnia: new perspectives on causes and consequences. Physiol Rev 2020; 101:995-1046. [PMID: 32790576 DOI: 10.1152/physrev.00046.2019] [Citation(s) in RCA: 163] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
While insomnia is the second most common mental disorder, progress in our understanding of underlying neurobiological mechanisms has been limited. The present review addresses the definition and prevalence of insomnia and explores its subjective and objective characteristics across the 24-hour day. Subsequently, the review extensively addresses how the vulnerability to develop insomnia is affected by genetic variants, early life stress, major life events, and brain structure and function. Further supported by the clear mental health risks conveyed by insomnia, the integrated findings suggest that the vulnerability to develop insomnia could rather be found in brain circuits regulating emotion and arousal than in circuits involved in circadian and homeostatic sleep regulation. Finally, a testable model is presented. The model proposes that in people with a vulnerability to develop insomnia, the locus coeruleus is more sensitive to-or receives more input from-the salience network and related circuits, even during rapid eye movement sleep, when it should normally be sound asleep. This vulnerability may ignite a downward spiral of insufficient overnight adaptation to distress, resulting in accumulating hyperarousal, which, in turn, impedes restful sleep and moreover increases the risk of other mental health adversity. Sensitized brain circuits are likely to be subjectively experienced as "sleeping with one eye open". The proposed model opens up the possibility for novel intervention studies and animal studies, thus accelerating the ignition of a neuroscience of insomnia, which is direly needed for better treatment.
Collapse
Affiliation(s)
- Eus J W Van Someren
- Department of Sleep and Cognition, Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands; Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit University Amsterdam, Amsterdam, The Netherlands; and Amsterdam UMC, Vrije Universiteit, Psychiatry, Amsterdam Neuroscience, Amsterdam, The Netherlands
| |
Collapse
|
31
|
Elshiekh A, Subramaniapillai S, Rajagopal S, Pasvanis S, Ankudowich E, Rajah MN. The association between cognitive reserve and performance-related brain activity during episodic encoding and retrieval across the adult lifespan. Cortex 2020; 129:296-313. [DOI: 10.1016/j.cortex.2020.05.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 02/26/2020] [Accepted: 05/02/2020] [Indexed: 01/23/2023]
|
32
|
de Mendonça A, Cardoso S, Maroco J, Guerreiro M, Carmo JC. The update of semantic memories in amnestic mild cognitive impairment. J Neuropsychol 2020; 15 Suppl 1:27-40. [PMID: 32542952 DOI: 10.1111/jnp.12217] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 04/01/2020] [Indexed: 12/19/2022]
Abstract
It is still controversial to what extent neocortical consolidated memories are susceptible of change by processes of reconsolidation and transformation throughout experience, and whether the medial temporal lobes are necessary for this update of semantic consolidated memories, as they are for episodic remembering. We hypothesize that patients with amnestic mild cognitive impairment (aMCI) who have deficits in episodic memory may also have difficulties in updating information on added new features of objects. Sixteen participants with aMCI and 20 healthy control participants performed a semantic word-to-picture task, in which they were asked to identify as belonging to a given semantic category NEW objects, that have incorporated novel features, as well as OLD items, semantically and visually SIMILAR items and UNRELATED items. Patients with aMCI made a greater percentage of errors than healthy controls. Participants globally made greater percentages of errors in difficult types of items, namely NEW and SIMILAR, as compared to easier ones, OLD and UNRELATED. Importantly, an item by diagnostic group interaction effect was observed, and post hoc analysis showed that patients with aMCI made a higher percentage of errors than controls in NEW items only. In conclusion, patients with aMCI had a particular difficulty in identifying the NEW items of the word-to-picture task as compared to the control participants, supporting the concept of a flexible and dynamic conceptual knowledge system, involving the update of semantic memories and the integration of new attributes in a constant transformation process, which is impaired in these patients.
Collapse
Affiliation(s)
| | | | - João Maroco
- Instituto Superior de Psicologia Aplicada, Lisboa, Portugal
| | | | - Joana C Carmo
- Faculdade de Psicologia, Universidade de Lisboa, Portugal
| |
Collapse
|
33
|
Wagner IC, Rütgen M, Lamm C. Pattern similarity and connectivity of hippocampal-neocortical regions support empathy for pain. Soc Cogn Affect Neurosci 2020; 15:273-284. [PMID: 32248233 PMCID: PMC7235961 DOI: 10.1093/scan/nsaa045] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 03/23/2020] [Accepted: 03/24/2020] [Indexed: 12/17/2022] Open
Abstract
Empathy is thought to engage mental simulation, which in turn is known to rely on hippocampal-neocortical processing. Here, we tested how hippocampal-neocortical pattern similarity and connectivity contributed to pain empathy. Using this approach, we analyzed a data set of 102 human participants who underwent functional MRI while painful and non-painful electrical stimulation was delivered to themselves or to a confederate. As hypothesized, results revealed increased pattern similarity between first-hand pain and pain empathy (compared to non-painful control conditions) within the hippocampus, retrosplenial cortex, the temporo-parietal junction and anterior insula. While representations in these regions were unaffected by confederate similarity, pattern similarity in the dorsal medial prefrontal cortex was increased the more dissimilar the other individual was perceived. Hippocampal-neocortical connectivity during first-hand pain and pain empathy engaged largely distinct but neighboring primary motor regions, and empathy-related hippocampal coupling with the fusiform gyrus positively scaled with trait measures of perspective taking. These findings suggest that shared representations and mental simulation might contribute to pain empathy via hippocampal-neocortical pattern similarity and connectivity, partially affected by personality traits and the similarity of the observed individual.
Collapse
Affiliation(s)
- Isabella C Wagner
- Social, Cognitive and Affective Neuroscience Unit, Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology, University of Vienna, Liebiggasse 5, Vienna 1010, Austria
| | - Markus Rütgen
- Social, Cognitive and Affective Neuroscience Unit, Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology, University of Vienna, Liebiggasse 5, Vienna 1010, Austria
| | - Claus Lamm
- Social, Cognitive and Affective Neuroscience Unit, Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology, University of Vienna, Liebiggasse 5, Vienna 1010, Austria
| |
Collapse
|
34
|
Bostancıklıoğlu M. An update on memory formation and retrieval: An engram-centric approach. Alzheimers Dement 2020; 16:926-937. [PMID: 32333509 DOI: 10.1002/alz.12071] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 09/26/2019] [Accepted: 01/03/2020] [Indexed: 01/10/2023]
Abstract
OBJECTIVE We explore here that memory loss observed in the early stage of Alzheimer's disease (AD) is a disorder of memory retrieval, instead of a storage impairment. This engram-centric explanation aims to enlarge the conceptual frame of memory as an emergent behavior of the brain and to propose a new treatment strategy for memory retrieval in dementia-AD. BACKGROUND The conventional memory hypothesis suggests that memory is stored as multiple traces in hippocampal neurons but recent evidence indicates that there are specialized memory engrams responsible for the storage and the retrieval of different memory types. UPDATED MEMORY HYPOTHESIS There are specialized memory engram neurons for each memory type and when information will be stored as a memory arrives in the hippocampus through afferent neurons finds its neuron according to the excitability states of engram neurons. The excitability level in engram neurons seems like a code canalizing the interactions between engrams and information. Therefore, to enhance the excitability of memory engram neurons improves memory loss observed in AD. In addition, we suggest that the hippocampus creates an index for information stored in memory engram cells in specialized regions for different types of memory, instead of storing all information; and different anatomic locations of engram cells and their roles in memory retrieval point out that memory could be an emergent behavior of the brain, and the interaction between serotonin fluctuation and engram neurons could be neural underpinnings of terminal lucidity. MAJOR CHALLENGES FOR THE MODEL The major challenge for this engram-centric memory retrieval model is the translation from bench to patient, specifically the delivery of optogenetic tools in patients. Engram neurons can be specifically activated by optogenetic tools, but optogenetics is an invasive technique which requires optic fiber implantation into the brain. In addition, light can overheat the tissue and thus induce damage in tissue. Furthermore, light is a foreign object and its direct implantation into the brain may cause neuroinflammation, the main trigger of neurodegenerative diseases. Therefore, to test the engram hypothesis in human, new tools to allow specific engram activation should be discovered.
Collapse
|
35
|
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: 11] [Impact Index Per Article: 2.8] [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.
Collapse
|
36
|
Ren J, Huang F, Zhou Y, Zhuang L, Xu J, Gao C, Qin S, Luo J. The function of the hippocampus and middle temporal gyrus in forming new associations and concepts during the processing of novelty and usefulness features in creative designs. Neuroimage 2020; 214:116751. [PMID: 32194284 DOI: 10.1016/j.neuroimage.2020.116751] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 03/13/2020] [Accepted: 03/13/2020] [Indexed: 12/16/2022] Open
Abstract
Creative thought relies on the reorganization of existing knowledge to generate novel and useful concepts. However, how these new concepts are formed, especially through the processing of novelty and usefulness (which are usually regarded as the key properties of creativity), is not clear. Taking familiar and useful (FU) objects/designs as the starting point or fundamental baseline, we modified them into novel and useless (NS) objects/designs or novel and useful (NU) ones (i.e., truly creative ones) to investigate how the features of novelty and usefulness are processed (processing of novelty: NU minus FU; processing of usefulness: NU minus NS). Specifically, we predicted that the creative integration of novelty and usefulness entails not only the formation of new associations, which could be critically mediated by the hippocampus and adjacent medial temporal lobe (MTL) areas, but also the formation of new concepts or categories, which is supported by the middle temporal gyrus (MTG). We found that both the MTL and the MTG were involved in the processing of novelty and usefulness. The MTG showed distinctive patterns of information processing, reflected by strengthened functional connectivity with the hippocampus to construct new concepts and strengthened functional connectivity with the executive control system to break the boundaries of old concepts. Additionally, participants' subjective evaluations of concept distance showed that the distance between the familiar concept (FU) and the successfully constructed concept (NU) was larger than that between the FU and the unsuccessfully constructed concept (NS), and this pattern was found to correspond to the patterns of their neural representations in the MTG. These findings demonstrate the critical mechanism by which new associations and concepts are formed during novelty and usefulness processing in creative design; this mechanism may be critically mediated by the hippocampus-MTG connection.
Collapse
Affiliation(s)
- Jingyuan Ren
- Beijing Key Laboratory of Learning and Cognition, School of Psychology, Capital Normal University, Beijing, 100048, China
| | - Furong Huang
- School of Psychology, Jiangxi Normal University, Nanchang, 330022, China
| | - Ying Zhou
- Beijing Key Laboratory of Learning and Cognition, School of Psychology, Capital Normal University, Beijing, 100048, China
| | - Liping Zhuang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Faculty of Psychology at Beijing Normal University, Beijing, 100875, China
| | - Jiahua Xu
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Faculty of Psychology at Beijing Normal University, Beijing, 100875, China
| | - Chuanji Gao
- Department of Psychology, Institute of Mind and Brain, University of South Carolina, Columbia, 29201, USA
| | - Shaozheng Qin
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Faculty of Psychology at Beijing Normal University, Beijing, 100875, China
| | - Jing Luo
- Beijing Key Laboratory of Learning and Cognition, School of Psychology, Capital Normal University, Beijing, 100048, China; Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, 100101, China.
| |
Collapse
|
37
|
Miller TD, Chong TTJ, Aimola Davies AM, Johnson MR, Irani SR, Husain M, Ng TWC, Jacob S, Maddison P, Kennard C, Gowland PA, Rosenthal CR. Human hippocampal CA3 damage disrupts both recent and remote episodic memories. eLife 2020; 9:e41836. [PMID: 31976861 PMCID: PMC6980860 DOI: 10.7554/elife.41836] [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: 09/21/2018] [Accepted: 12/05/2019] [Indexed: 12/31/2022] Open
Abstract
Neocortical-hippocampal interactions support new episodic (event) memories, but there is conflicting evidence about the dependence of remote episodic memories on the hippocampus. In line with systems consolidation and computational theories of episodic memory, evidence from model organisms suggests that the cornu ammonis 3 (CA3) hippocampal subfield supports recent, but not remote, episodic retrieval. In this study, we demonstrated that recent and remote memories were susceptible to a loss of episodic detail in human participants with focal bilateral damage to CA3. Graph theoretic analyses of 7.0-Tesla resting-state fMRI data revealed that CA3 damage disrupted functional integration across the medial temporal lobe (MTL) subsystem of the default network. The loss of functional integration in MTL subsystem regions was predictive of autobiographical episodic retrieval performance. We conclude that human CA3 is necessary for the retrieval of episodic memories long after their initial acquisition and functional integration of the default network is important for autobiographical episodic memory performance.
Collapse
Affiliation(s)
- Thomas D Miller
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUnited Kingdom
- Department of NeurologyRoyal Free HospitalLondonUnited Kingdom
| | - Trevor T-J Chong
- Monash Institute of Cognitive and Clinical NeurosciencesMonash UniversityClaytonAustralia
| | - Anne M Aimola Davies
- Department of Experimental PsychologyUniversity of OxfordOxfordUnited Kingdom
- Research School of PsychologyAustralian National UniversityCanberraAustralia
| | - Michael R Johnson
- Division of Brain SciencesImperial College LondonLondonUnited Kingdom
| | - Sarosh R Irani
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUnited Kingdom
| | - Masud Husain
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUnited Kingdom
- Department of Experimental PsychologyUniversity of OxfordOxfordUnited Kingdom
| | - Tammy WC Ng
- Department of AnaesthesticsRoyal Free HospitalLondonUnited Kingdom
| | - Saiju Jacob
- Neurology Department, Queen Elizabeth Neuroscience CentreUniversity Hospitals of BirminghamBirminghamUnited Kingdom
| | - Paul Maddison
- Neurology DepartmentQueen’s Medical CentreNottinghamUnited Kingdom
| | - Christopher Kennard
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUnited Kingdom
| | - Penny A Gowland
- Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and AstronomyUniversity of NottinghamNottinghamUnited Kingdom
| | - Clive R Rosenthal
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUnited Kingdom
| |
Collapse
|
38
|
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: 42] [Impact Index Per Article: 10.5] [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.
Collapse
|
39
|
De Zeeuw CI, Canto CB. Sleep deprivation directly following eyeblink-conditioning impairs memory consolidation. Neurobiol Learn Mem 2020; 170:107165. [PMID: 31953233 PMCID: PMC7184677 DOI: 10.1016/j.nlm.2020.107165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 12/05/2019] [Accepted: 01/12/2020] [Indexed: 10/31/2022]
Abstract
The relation between sleep and different forms of memory formation continues to be a relevant topic in our daily life. Sleep has been found to affect cerebellum-dependent procedural memory formation, but it remains to be elucidated to what extent the level of sleep deprivation directly after motor training also influences our ability to store and retrieve memories. Here, we studied the effect of disturbed sleep in mice during two different time-windows, one covering the first four hours following eyeblink conditioning (EBC) and another window following the next period of four hours. Compared to control mice with sleep ad libitum, the percentage of conditioned responses and their amplitude were impaired when mice were deprived of sleep directly after conditioning. This impairment was still significant when the learned EBC responses were extinguished and later reacquired. However, consolidation of eyeblink responses was not affected when mice were deprived later than four hours after acquisition, not even when tested during a different day-night cycle for control. Moreover, mice that slept longer directly following EBC showed a tendency for more conditioned responses. Our data indicate that consolidation of motor memories can benefit from sleep directly following memory formation.
Collapse
Affiliation(s)
- Chris I De Zeeuw
- Netherlands Institute for Neuroscience, KNAW, 1105 BA Amsterdam, the Netherlands; Department of Neuroscience, Erasmus MC, 3000 CA Rotterdam, the Netherlands
| | - Cathrin B Canto
- Netherlands Institute for Neuroscience, KNAW, 1105 BA Amsterdam, the Netherlands; Department of Neuroscience, Erasmus MC, 3000 CA Rotterdam, the Netherlands.
| |
Collapse
|
40
|
Association of Physical Activity on Memory and Executive Function: Population-Based National Sample of Older Adults. JOURNAL OF COGNITIVE ENHANCEMENT 2019. [DOI: 10.1007/s41465-019-00127-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
41
|
Fargier R, Laganaro M. Neural dynamics of the production of newly acquired words relative to well-known words. Brain Res 2019; 1727:146557. [PMID: 31738889 DOI: 10.1016/j.brainres.2019.146557] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 11/06/2019] [Accepted: 11/13/2019] [Indexed: 10/25/2022]
Abstract
An adult continues acquiring new lexical entries in everyday life. Brain networks and processes at play when producing newly learnt words might be similar to well-known words, yet some processes are bound to be slower. Here, we compared the neural dynamics of producing newly acquired words with those of well-known frequent words, both qualitatively and quantitatively, using event-related potentials (ERPs) associated to high-density microstate analyses. ERPs revealed several temporal windows with differences in waveform amplitudes, which correspond to enhanced duration of similar microstates for newly acquired words compared to well-known words. The time-periods of these ERP modulations converged to suggest that both lexical processes and word form encoding are slowed down for words that have been learned recently, but that the same brain processes are implemented as for well-known words.
Collapse
Affiliation(s)
| | - Marina Laganaro
- Faculty of Psychology and Educational Sciences, University of Geneva, Switzerland
| |
Collapse
|
42
|
Du X, Zhan L, Chen G, Guo D, Li C, Moscovitch M, Yang J. Differential activation of the medial temporal lobe during item and associative memory across time. Neuropsychologia 2019; 135:107252. [PMID: 31698009 DOI: 10.1016/j.neuropsychologia.2019.107252] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 10/26/2019] [Accepted: 11/01/2019] [Indexed: 11/26/2022]
Abstract
Studies have shown that the hippocampus plays a crucial role in associative memory. One central issue is whether the involvement of the hippocampus in associative memory remains stable or declines with the passage of time. In the majority of studies, memory performance declines with delay, confounding attempts at interpreting differences in hippocampal activation over time. To address this issue, we tried to equate behavioral performance as much as possible across time for memory of items and associations separately. After encoding words and word pairs, participants were tested for item and associative memories at four time intervals: 20-min, 1-day, 1-week, and 1-month. The results revealed that MTL activation differed over time for associative and item memories. For associative memory, the activation of the anterior hippocampus decreased from 20-min to 1-day then remained stable, whereas in the posterior hippocampus, the activation was comparable for different time intervals when old pairs were correctly retrieved. The hippocampal activation also remained stable when recombined pairs were correctly rejected. As this condition controls for familiarity of the individual items, correct performance depends only on associative memory. For item memory, hippocampal activation declined progressively from 20-min to 1-week and remained stable afterwards. By contrast, the activation in the perirhinal/entorhinal cortex increased over time irrespective of item and associative memories. Drawing on Tulving's distinction between recollection and familiarity, we interpret this pattern of results in accordance with Trace Transformation Theory, which states that as memories are transformed with time and experience, the neural structures mediating item and associative memories will vary according to the underlying representations to which the memories have been transformed.
Collapse
Affiliation(s)
- Xiaoya Du
- School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, PR China
| | - Lexia Zhan
- School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, PR China
| | - Gang Chen
- Scientific and Statistical Computing Core, NIMH/NIH, Bethesda, MD, USA
| | - Dingrong Guo
- School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, PR China
| | - Cuihong Li
- School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, PR China
| | - Morris Moscovitch
- Department of Psychology, University of Toronto, Toronto, Canada; Rotman Research Institute, Baycrest Centre, Toronto, Canada.
| | - Jiongjiong Yang
- School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, PR China.
| |
Collapse
|
43
|
Ferreira C, Charest I, Wimber M. Retrieval aids the creation of a generalised memory trace and strengthens episode-unique information. Neuroimage 2019; 201:115996. [DOI: 10.1016/j.neuroimage.2019.07.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 06/28/2019] [Accepted: 07/04/2019] [Indexed: 12/18/2022] Open
|
44
|
Guo D, Yang J. Interplay of the long axis of the hippocampus and ventromedial prefrontal cortex in schema-related memory retrieval. Hippocampus 2019; 30:263-277. [PMID: 31490611 DOI: 10.1002/hipo.23154] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 08/05/2019] [Accepted: 08/23/2019] [Indexed: 01/01/2023]
Abstract
When new information is relevant to prior knowledge or schema, it can be learned and remembered better. Rodent studies have suggested that the hippocampus and ventromedial prefrontal cortex (vmPFC) are important for processing schema-related information. However, there are inconsistent findings from human studies on the involvement of the hippocampus and its interaction with the vmPFC in schema-related memory retrieval. To address these issues, we used a human analog of the rodent spatial schema task to compare brain activity during immediate retrieval of paired associations (PAs) in schema-consistent and schema-inconsistent conditions. The results showed that the anterior hippocampus was more involved in retrieving PAs in the schema-consistent condition than in the schema-inconsistent condition. Connectivity analyses showed that the anterior hippocampus had stronger coupling with the vmPFC when the participants retrieved newly learned PAs successfully in the schema-consistent (vs. schema-inconsistent) condition, whereas the coupling of the posterior hippocampus with the vmPFC showed the opposite. Taken together, the results shed light on how the long axis of the hippocampus and vmPFC interact to serve memory retrieval via different networks that differ by schema condition.
Collapse
Affiliation(s)
- Dingrong Guo
- School of Psychological and Cognitive Sciences, Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, China
| | - Jiongjiong Yang
- School of Psychological and Cognitive Sciences, Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, China
| |
Collapse
|
45
|
Hanoğlu L, Ercan FB, Mantar N, Helvacı Yılmaz N, Sitrava S, Özer F, Yuluğ B. Accelerated forgetting and verbal memory consolidation process in idiopathic nondement Parkinson's disease. J Clin Neurosci 2019; 70:208-213. [PMID: 31473091 DOI: 10.1016/j.jocn.2019.08.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 08/04/2019] [Indexed: 11/18/2022]
Abstract
OBJECTIVE Episodic memory impairment and underlying pathophysiology in Parkinson's Disease (PD) is poorly investigated. Formerly, it was thought to be a secondary effect of impairment in fronto-striatal circuit. However, recent studies hypothesized that there is a dual progression of PD and memory loss is possibly related to posterior cortex rather than frontal. To understand the impairment, underlying mechanisms should be investigated. Although consolidation is one of these mechanisms consolidation phase of episodic memory in PD was not investigated yet. Recently accelerated long term forgetting (ALF) phenomenon is emphasized in consolidation researches. METHOD Here it is evaluated the presence of accelerated long-term forgetting in nondemented PD as a consequence of a deficit in consolidation process. 32 patients and 33 controls participated in the study. Turkish Verbal Memory Process Test (VMPT) was applied to both groups. Delayed recall (DR) scores collected after 30 min, one week and six weeks. Forgetting rates were calculated based on these scores. RESULTS There was significant difference in DR scores of patients compared to controls in the 30th minute and sixth week. Forgetting rate between 30th minute-1st week did not differ but 1st-6th week was found statistically significant across groups. CONCLUSIONS To the best of our knowledge, this is the first study investigating verbal memory consolidation in PD. Results suggested that impairment is possibly related to the late phase of consolidation of verbal memory in neocortex.
Collapse
Affiliation(s)
- L Hanoğlu
- Istanbul Medipol University, Institute of Medical Science, Department of Neuroscience, Istanbul, Turkey; Istanbul Medipol University, REMER, Clinical Electrophysiology, Neuroimaging and Neuromodulation Laboratory, Istanbul, Turkey; Istanbul Medipol University, School of Medicine, Department of Neurology, Istanbul, Turkey
| | - F B Ercan
- Istanbul Medipol University, Institute of Medical Science, Department of Neuroscience, Istanbul, Turkey.
| | - N Mantar
- Istanbul Medipol University, Institute of Medical Science, Department of Neuroscience, Istanbul, Turkey
| | - N Helvacı Yılmaz
- Istanbul Medipol University, School of Medicine, Department of Neurology, Istanbul, Turkey
| | - S Sitrava
- Istanbul Medipol University, Psychological Counseling Center, Istanbul, Turkey
| | - F Özer
- Koç University, Topkapı Hospital, Department of Neurology, Istanbul, Turkey
| | - B Yuluğ
- Alanya University, Faculty of Medicine, Department of Neurology, Antalya, Turkey
| |
Collapse
|
46
|
Klinzing JG, Niethard N, Born J. Mechanisms of systems memory consolidation during sleep. Nat Neurosci 2019; 22:1598-1610. [PMID: 31451802 DOI: 10.1038/s41593-019-0467-3] [Citation(s) in RCA: 452] [Impact Index Per Article: 90.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 07/12/2019] [Indexed: 02/06/2023]
Abstract
Long-term memory formation is a major function of sleep. Based on evidence from neurophysiological and behavioral studies mainly in humans and rodents, we consider the formation of long-term memory during sleep as an active systems consolidation process that is embedded in a process of global synaptic downscaling. Repeated neuronal replay of representations originating from the hippocampus during slow-wave sleep leads to a gradual transformation and integration of representations in neocortical networks. We highlight three features of this process: (i) hippocampal replay that, by capturing episodic memory aspects, drives consolidation of both hippocampus-dependent and non-hippocampus-dependent memory; (ii) brain oscillations hallmarking slow-wave and rapid-eye movement sleep that provide mechanisms for regulating both information flow across distant brain networks and local synaptic plasticity; and (iii) qualitative transformations of memories during systems consolidation resulting in abstracted, gist-like representations.
Collapse
Affiliation(s)
- Jens G Klinzing
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany.,Center for Integrative Neuroscience, 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. .,Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.
| |
Collapse
|
47
|
Sekeres MJ, Winocur G, Moscovitch M, Anderson JAE, Pishdadian S, Martin Wojtowicz J, St-Laurent M, McAndrews MP, Grady CL. Changes in patterns of neural activity underlie a time-dependent transformation of memory in rats and humans. Hippocampus 2019; 28:745-764. [PMID: 29989271 DOI: 10.1002/hipo.23009] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 06/25/2018] [Accepted: 06/29/2018] [Indexed: 11/06/2022]
Abstract
The dynamic process of memory consolidation involves a reorganization of brain regions that support a memory trace over time, but exactly how the network reorganizes as the memory changes remains unclear. We present novel converging evidence from studies of animals (rats) and humans for the time-dependent reorganization and transformation of different types of memory as measured both by behavior and brain activation. We find that context-specific memories in rats, and naturalistic episodic memories in humans, lose precision over time and activity in the hippocampus decreases. If, however, the retrieved memories retain contextual or perceptual detail, the hippocampus is engaged similarly at recent and remote timepoints. As the interval between the timepoint increases, the medial prefrontal cortex is engaged increasingly during memory retrieval, regardless of the context or the amount of retrieved detail. Moreover, these hippocampal-frontal shifts are accompanied by corresponding changes in a network of cortical structures mediating perceptually-detailed as well as less precise, schematic memories. These findings provide cross-species evidence for the crucial interplay between hippocampus and neocortex that reflects changes in memory representation over time and underlies systems consolidation.
Collapse
Affiliation(s)
- Melanie J Sekeres
- Rotman Research Institute, Toronto, Ontario, Canada.,Department of Psychology and Neuroscience, Department of Biology, Baylor University, Waco, Texas.,Department of Psychology, University of Toronto, Toronto, Ontario, Canada
| | - Gordon Winocur
- Rotman Research Institute, Toronto, Ontario, Canada.,Department of Psychology, University of Toronto, Toronto, Ontario, Canada.,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.,Department of Psychology, Trent University, Peterborough, Ontario, Canada
| | - Morris Moscovitch
- Rotman Research Institute, Toronto, Ontario, Canada.,Department of Psychology, University of Toronto, Toronto, Ontario, Canada.,Department of Psychology, Baycrest, Toronto, Ontario, Canada
| | - John A E Anderson
- Rotman Research Institute, Toronto, Ontario, Canada.,Department of Psychology, University of Toronto, Toronto, Ontario, Canada.,Department of Psychology, York University, Toronto, Ontario, Canada
| | - Sara Pishdadian
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada.,Department of Psychology, York University, Toronto, Ontario, Canada
| | - J Martin Wojtowicz
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | | | - Mary Pat McAndrews
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada.,Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Cheryl L Grady
- Rotman Research Institute, Toronto, Ontario, Canada.,Department of Psychology, University of Toronto, Toronto, Ontario, Canada.,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
48
|
Wagner IC, van Buuren M, Fernández G. Thalamo-cortical coupling during encoding and consolidation is linked to durable memory formation. Neuroimage 2019; 197:80-92. [DOI: 10.1016/j.neuroimage.2019.04.055] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 04/19/2019] [Indexed: 01/08/2023] Open
|
49
|
Yonelinas AP, Ranganath C, Ekstrom AD, Wiltgen BJ. A contextual binding theory of episodic memory: systems consolidation reconsidered. Nat Rev Neurosci 2019; 20:364-375. [PMID: 30872808 PMCID: PMC7233541 DOI: 10.1038/s41583-019-0150-4] [Citation(s) in RCA: 198] [Impact Index Per Article: 39.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Episodic memory reflects the ability to recollect the temporal and spatial context of past experiences. Episodic memories depend on the hippocampus but have been proposed to undergo rapid forgetting unless consolidated during offline periods such as sleep to neocortical areas for long-term storage. Here, we propose an alternative to this standard systems consolidation theory (SSCT) - a contextual binding account - in which the hippocampus binds item-related and context-related information. We compare these accounts in light of behavioural, lesion, neuroimaging and sleep studies of episodic memory and contend that forgetting is largely due to contextual interference, episodic memory remains dependent on the hippocampus across time, contextual drift produces post-encoding activity and sleep benefits memory by reducing contextual interference.
Collapse
Affiliation(s)
| | - Charan Ranganath
- Center for Neuroscience, University of California, Davis, CA, USA
| | - Arne D Ekstrom
- Department of Psychology, University of Arizona, Tucson, AZ, USA
| | - Brian J Wiltgen
- Center for Neuroscience, University of California, Davis, CA, USA
| |
Collapse
|
50
|
Runyan JD, Moore AN, Dash PK. Coordinating what we’ve learned about memory consolidation: Revisiting a unified theory. Neurosci Biobehav Rev 2019; 100:77-84. [DOI: 10.1016/j.neubiorev.2019.02.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 02/08/2019] [Accepted: 02/16/2019] [Indexed: 10/27/2022]
|