1
|
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: 201] [Impact Index Per Article: 40.2] [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
|
2
|
Sopp MR, Brueckner AH, Schäfer SK, Lass-Hennemann J, Michael T. Differential effects of sleep on explicit and implicit memory for potential trauma reminders: findings from an analogue study. Eur J Psychotraumatol 2019; 10:1644128. [PMID: 31448066 PMCID: PMC6691831 DOI: 10.1080/20008198.2019.1644128] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 06/19/2019] [Accepted: 06/24/2019] [Indexed: 12/16/2022] Open
Abstract
Background: Recent findings suggest that disruptions of sleep-related memory processing are involved in the development of posttraumatic stress symptoms. More specifically, exposure to an analogue traumatic event resulted in fewer intrusive memories, when it was followed by sleep instead of continued wakefulness. However, competing evidence suggests that sleep deprivation may reduce intrusive re-experiencing. To address these conflicting accounts, we examined how sleep - as opposed to partial sleep deprivation - modulates explicit and implicit trauma memory using an analogue procedure. Methods: Healthy participants (N = 41) were assigned to a Sleep or Partial sleep deprivation group. Prior to nocturnal sleep, both groups were exposed to "traumatic" picture stories. After sleep or partial sleep deprivation, participants were subjected to tests of explicit and implicit memory for potential trauma reminders. Thereafter, participants completed an intrusion triggering task that was embedded in a distractor task. Results: Analyses revealed higher explicit memory for potential trauma reminders after sleep as compared to partial sleep deprivation. No group differences were found for implicit memory. Participants responded with fewer intrusions after sleep than following partial sleep deprivation. Conclusions: The current findings support a protective role of sleep in trauma memory processing, which may be evident after the first night of sleep post-trauma. Although more research is needed, our results corroborate the importance of promoting restful sleep in trauma-exposed individuals.
Collapse
Affiliation(s)
- M Roxanne Sopp
- Division of Clinical Psychology and Psychotherapy, Department of Psychology, Saarland University, Saarbrücken, Germany
| | - Alexandra H Brueckner
- Division of Clinical Psychology and Psychotherapy, Department of Psychology, Saarland University, Saarbrücken, Germany
| | - Sarah K Schäfer
- Division of Clinical Psychology and Psychotherapy, Department of Psychology, Saarland University, Saarbrücken, Germany
| | - Johanna Lass-Hennemann
- Division of Clinical Psychology and Psychotherapy, Department of Psychology, Saarland University, Saarbrücken, Germany
| | - Tanja Michael
- Division of Clinical Psychology and Psychotherapy, Department of Psychology, Saarland University, Saarbrücken, Germany
| |
Collapse
|
3
|
Sleep selectively stabilizes contextual aspects of negative memories. Sci Rep 2018; 8:17861. [PMID: 30552343 PMCID: PMC6294767 DOI: 10.1038/s41598-018-35999-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 11/08/2018] [Indexed: 11/09/2022] Open
Abstract
Sleep and emotion are both powerful modulators of the long-term stability of episodic memories, but precisely how these factors interact remains unresolved. We assessed changes in item recognition, contextual memory, and affective tone for negative and neutral memories across a 12 h interval containing sleep or wakefulness in 71 human volunteers. Our data indicate a sleep-dependent stabilization of negative contextual memories, in a way not seen for neutral memories, item recognition, or across wakefulness. Furthermore, retention of contextual memories was positively associated with the proportion of time spent in non-rapid eye movement sleep in a valence-independent manner. Finally, while affective responses to previously seen negative stimuli and to both old and new neutral stimuli decreased across an interval of sleep, effects for memorized items did not differ reliably between sleep and wake. These results add to our understanding of the complex interrelations among sleep, memory, and emotion.
Collapse
|
4
|
Doxey CR, Hodges CB, Bodily TA, Muncy NM, Kirwan CB. The effects of sleep on the neural correlates of pattern separation. Hippocampus 2017; 28:108-120. [DOI: 10.1002/hipo.22814] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 10/24/2017] [Accepted: 11/09/2017] [Indexed: 01/08/2023]
Affiliation(s)
| | - Cooper B. Hodges
- Department of Psychology; Brigham Young University; Provo Utah 84602
| | - Ty A. Bodily
- Neuroscience Center, Brigham Young University; Provo Utah 84602
| | - Nathan M. Muncy
- Department of Psychology; Brigham Young University; Provo Utah 84602
| | - C. Brock Kirwan
- Neuroscience Center, Brigham Young University; Provo Utah 84602
- Department of Psychology; Brigham Young University; Provo Utah 84602
| |
Collapse
|
5
|
Remembering specific features of emotional events across time: The role of REM sleep and prefrontal theta oscillations. COGNITIVE AFFECTIVE & BEHAVIORAL NEUROSCIENCE 2017; 17:1186-1209. [DOI: 10.3758/s13415-017-0542-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
|
6
|
Gervais NJ, Mong JA, Lacreuse A. Ovarian hormones, sleep and cognition across the adult female lifespan: An integrated perspective. Front Neuroendocrinol 2017; 47:134-153. [PMID: 28803147 PMCID: PMC7597864 DOI: 10.1016/j.yfrne.2017.08.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 08/07/2017] [Accepted: 08/08/2017] [Indexed: 12/22/2022]
Abstract
Loss of ovarian function in women is associated with sleep disturbances and cognitive decline, which suggest a key role for estrogens and/or progestins in modulating these symptoms. The effects of ovarian hormones on sleep and cognitive processes have been studied in separate research fields that seldom intersect. However, sleep has a considerable impact on cognitive function. Given the tight connections between sleep and cognition, ovarian hormones may influence selective aspects of cognition indirectly, via the modulation of sleep. In support of this hypothesis, a growing body of evidence indicates that the development of sleep disorders following menopause contributes to accelerated cognitive decline and dementia in older women. This paper draws from both the animal and human literature to present an integrated view of the effects of ovarian hormones on sleep and cognition across the adult female lifespan.
Collapse
Affiliation(s)
- Nicole J Gervais
- Department of Psychological and Brain Sciences, University of Massachusetts, Amherst, 135 Hicks Way, Amherst, MA 01003, United States.
| | - Jessica A Mong
- Department of Pharmacology, University of Maryland School of Medicine, 655 West Baltimore Street, Baltimore, MD 21201, United States
| | - Agnès Lacreuse
- Department of Psychological and Brain Sciences, University of Massachusetts, Amherst, 135 Hicks Way, Amherst, MA 01003, United States
| |
Collapse
|
7
|
Studte S, Bridger E, Mecklinger A. Sleep spindles during a nap correlate with post sleep memory performance for highly rewarded word-pairs. BRAIN AND LANGUAGE 2017; 167:28-35. [PMID: 27129616 DOI: 10.1016/j.bandl.2016.03.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 02/23/2016] [Accepted: 03/23/2016] [Indexed: 05/02/2023]
Abstract
The consolidation of new associations is thought to depend in part on physiological processes engaged during non-REM (NREM) sleep, such as slow oscillations and sleep spindles. Moreover, NREM sleep is thought to selectively benefit associations that are adaptive for the future. In line with this, the current study investigated whether different reward cues at encoding are associated with changes in sleep physiology and memory retention. Participants' associative memory was tested after learning a list of arbitrarily paired words both before and after taking a 90-min nap. During learning, word-pairs were preceded by a cue indicating either a high or a low reward for correct memory performance at test. The motivation manipulation successfully impacted retention such that memory declined to a greater extent from pre- to post sleep for low rewarded than for high rewarded word-pairs. In line with previous studies, positive correlations between spindle density during NREM sleep and general memory performance pre- and post-sleep were found. In addition to this, however, a selective positive relationship between memory performance for highly rewarded word-pairs at posttest and spindle density during NREM sleep was also observed. These results support the view that motivationally salient memories are preferentially consolidated and that sleep spindles may be an important underlying mechanism for selective consolidation.
Collapse
Affiliation(s)
- Sara Studte
- Experimental Neuropsychology Unit, Saarland University, Germany.
| | - Emma Bridger
- Department of Psychology, Birmingham City University, UK.
| | - Axel Mecklinger
- Experimental Neuropsychology Unit, Saarland University, Germany.
| |
Collapse
|
8
|
Maurer L, Zitting KM, Elliott K, Czeisler CA, Ronda JM, Duffy JF. A new face of sleep: The impact of post-learning sleep on recognition memory for face-name associations. Neurobiol Learn Mem 2015; 126:31-8. [PMID: 26549626 DOI: 10.1016/j.nlm.2015.10.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 10/22/2015] [Accepted: 10/28/2015] [Indexed: 12/01/2022]
Abstract
Sleep has been demonstrated to improve consolidation of many types of new memories. However, few prior studies have examined how sleep impacts learning of face-name associations. The recognition of a new face along with the associated name is an important human cognitive skill. Here we investigated whether post-presentation sleep impacts recognition memory of new face-name associations in healthy adults. Fourteen participants were tested twice. Each time, they were presented 20 photos of faces with a corresponding name. Twelve hours later, they were shown each face twice, once with the correct and once with an incorrect name, and asked if each face-name combination was correct and to rate their confidence. In one condition the 12-h interval between presentation and recall included an 8-h nighttime sleep opportunity ("Sleep"), while in the other condition they remained awake ("Wake"). There were more correct and highly confident correct responses when the interval between presentation and recall included a sleep opportunity, although improvement between the "Wake" and "Sleep" conditions was not related to duration of sleep or any sleep stage. These data suggest that a nighttime sleep opportunity improves the ability to correctly recognize face-name associations. Further studies investigating the mechanism of this improvement are important, as this finding has implications for individuals with sleep disturbances and/or memory impairments.
Collapse
Affiliation(s)
- Leonie Maurer
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, 221 Longwood Avenue, BLI438, Boston, MA, USA; Department of Psychology, University of Konstanz, 78457 Konstanz, Germany.
| | - Kirsi-Marja Zitting
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, 221 Longwood Avenue, BLI438, Boston, MA, USA; Division of Sleep Medicine, Harvard Medical School, 221 Longwood Avenue, BLI438, Boston, MA, USA.
| | - Kieran Elliott
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, 221 Longwood Avenue, BLI438, Boston, MA, USA.
| | - Charles A Czeisler
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, 221 Longwood Avenue, BLI438, Boston, MA, USA; Division of Sleep Medicine, Harvard Medical School, 221 Longwood Avenue, BLI438, Boston, MA, USA.
| | - Joseph M Ronda
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, 221 Longwood Avenue, BLI438, Boston, MA, USA; Division of Sleep Medicine, Harvard Medical School, 221 Longwood Avenue, BLI438, Boston, MA, USA.
| | - Jeanne F Duffy
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, 221 Longwood Avenue, BLI438, Boston, MA, USA; Division of Sleep Medicine, Harvard Medical School, 221 Longwood Avenue, BLI438, Boston, MA, USA.
| |
Collapse
|
9
|
Buzsáki G. Hippocampal sharp wave-ripple: A cognitive biomarker for episodic memory and planning. Hippocampus 2015; 25:1073-188. [PMID: 26135716 PMCID: PMC4648295 DOI: 10.1002/hipo.22488] [Citation(s) in RCA: 939] [Impact Index Per Article: 104.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 06/30/2015] [Indexed: 12/23/2022]
Abstract
Sharp wave ripples (SPW-Rs) represent the most synchronous population pattern in the mammalian brain. Their excitatory output affects a wide area of the cortex and several subcortical nuclei. SPW-Rs occur during "off-line" states of the brain, associated with consummatory behaviors and non-REM sleep, and are influenced by numerous neurotransmitters and neuromodulators. They arise from the excitatory recurrent system of the CA3 region and the SPW-induced excitation brings about a fast network oscillation (ripple) in CA1. The spike content of SPW-Rs is temporally and spatially coordinated by a consortium of interneurons to replay fragments of waking neuronal sequences in a compressed format. SPW-Rs assist in transferring this compressed hippocampal representation to distributed circuits to support memory consolidation; selective disruption of SPW-Rs interferes with memory. Recently acquired and pre-existing information are combined during SPW-R replay to influence decisions, plan actions and, potentially, allow for creative thoughts. In addition to the widely studied contribution to memory, SPW-Rs may also affect endocrine function via activation of hypothalamic circuits. Alteration of the physiological mechanisms supporting SPW-Rs leads to their pathological conversion, "p-ripples," which are a marker of epileptogenic tissue and can be observed in rodent models of schizophrenia and Alzheimer's Disease. Mechanisms for SPW-R genesis and function are discussed in this review.
Collapse
Affiliation(s)
- György Buzsáki
- The Neuroscience Institute, School of Medicine and Center for Neural Science, New York University, New York, New York
| |
Collapse
|
10
|
Goldschmied JR, Cheng P, Kim HS, Casement M, Armitage R, Deldin PJ. Slow-wave disruption enhances the accessibility of positive memory traces. Neurobiol Learn Mem 2015; 125:168-75. [PMID: 26409320 DOI: 10.1016/j.nlm.2015.09.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 09/04/2015] [Accepted: 09/08/2015] [Indexed: 12/18/2022]
Abstract
The purpose of this study was to explore the effects of slow-wave disruption on positive and negative word recognition in a sample of healthy control participants and those with major depressive disorder. Prior to sleep, participants learned a set of emotional and neutral words during an encoding task by responding whether or not the word described them. Following baseline sleep, participants underwent one night of selective slow-wave disruption by auditory stimuli. Accuracy and reaction time to a recognition word set, including both positive and negative words, was assessed in the morning. Repeated-measures ANOVA revealed a significant interaction between word valence and condition, with positive words recognized significantly faster than negative words after disruption, in only healthy control participants. There were no significant results in those with major depressive disorder, or with regard to accuracy. These results may add to the increasing body of literature suggesting a hedonic bias to positive stimuli following sleep disruption.
Collapse
Affiliation(s)
- Jennifer R Goldschmied
- Department of Psychology, University of Michigan, 530 Church St, Ann Arbor, MI 48109, United States.
| | - Philip Cheng
- Department of Psychology, University of Michigan, 530 Church St, Ann Arbor, MI 48109, United States.
| | - Hyang Sook Kim
- Department of Psychology, University of Michigan, 530 Church St, Ann Arbor, MI 48109, United States.
| | - Melynda Casement
- Department of Psychology, University of Michigan, 530 Church St, Ann Arbor, MI 48109, United States.
| | - Roseanne Armitage
- Department of Psychiatry, University of Michigan, 4250 Plymouth Rd, Ann Arbor, MI 48109, United States.
| | - Patricia J Deldin
- Department of Psychology, University of Michigan, 530 Church St, Ann Arbor, MI 48109, United States.
| |
Collapse
|
11
|
Westerberg CE, Florczak SM, Weintraub S, Mesulam MM, Marshall L, Zee PC, Paller KA. Memory improvement via slow-oscillatory stimulation during sleep in older adults. Neurobiol Aging 2015; 36:2577-86. [PMID: 26116933 PMCID: PMC4523433 DOI: 10.1016/j.neurobiolaging.2015.05.014] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 05/20/2015] [Accepted: 05/22/2015] [Indexed: 11/21/2022]
Abstract
We examined the intriguing but controversial idea that disrupted sleep-dependent consolidation contributes to age-related memory decline. Slow-wave activity during sleep may help strengthen neural connections and provide memories with long-term stability, in which case decreased slow-wave activity in older adults could contribute to their weaker memories. One prediction from this account is that age-related memory deficits should be reduced by artificially enhancing slow-wave activity. In young adults, applying transcranial current oscillating at a slow frequency (0.75 Hz) during sleep improves memory. Here, we tested whether this procedure can improve memory in older adults. In 2 sessions separated by 1 week, we applied either slow-oscillatory stimulation or sham stimulation during an afternoon nap in a double-blind, crossover design. Memory tests were administered before and after sleep. A larger improvement in word-pair recall and higher slow-wave activity was observed with slow-oscillatory stimulation than with sham stimulation. This is the first demonstration that this procedure can improve memory in older adults, suggesting that declarative memory performance in older adults is partly dependent on slow-wave activity during sleep.
Collapse
Affiliation(s)
- Carmen E Westerberg
- Department of Psychology, Texas State University, San Marcos, TX, USA; Department of Psychology, Northwestern University, Evanston, IL, USA; Interdepartmental Neuroscience Program, Northwestern University, Evanston, IL, USA.
| | - Susan M Florczak
- Department of Psychology, Northwestern University, Evanston, IL, USA; Interdepartmental Neuroscience Program, Northwestern University, Evanston, IL, USA
| | - Sandra Weintraub
- Interdepartmental Neuroscience Program, Northwestern University, Evanston, IL, USA; Cognitive Neurology and Alzheimer's Disease Center, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - M-Marsel Mesulam
- Interdepartmental Neuroscience Program, Northwestern University, Evanston, IL, USA; Cognitive Neurology and Alzheimer's Disease Center, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Lisa Marshall
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Phyllis C Zee
- Interdepartmental Neuroscience Program, Northwestern University, Evanston, IL, USA; Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Ken A Paller
- Department of Psychology, Northwestern University, Evanston, IL, USA; Interdepartmental Neuroscience Program, Northwestern University, Evanston, IL, USA
| |
Collapse
|
12
|
Studte S, Bridger E, Mecklinger A. Nap sleep preserves associative but not item memory performance. Neurobiol Learn Mem 2015; 120:84-93. [PMID: 25732251 DOI: 10.1016/j.nlm.2015.02.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 02/11/2015] [Accepted: 02/21/2015] [Indexed: 10/23/2022]
Abstract
Many studies have shown that sleep improves memory performance, and that even short naps during the day are beneficial. Certain physiological components of sleep such as spindles and slow-wave-sleep are thought to be particularly important for memory consolidation. The aim of this experiment was to reveal the role of naps for hippocampus-dependent associative memory (AM) and hippocampus-independent item memory (IM) alongside their corresponding ERP old/new effects. Participants learnt single words and word-pairs before performing an IM- and an AM-test (baseline). One group was subsequently allowed to nap (∼90min) while the other watched DVDs (control group). Afterwards, both groups performed a final IM- and AM-test for the learned stimuli (posttest). IM performance decreased for both groups, while AM performance decreased for the control group but remained constant for the nap group, consistent with predictions concerning the selective impact of napping on hippocampus-dependent recognition. Putative ERP correlates of familiarity and recollection were observed in the IM posttest, whereas only the later recollection-related effect was present in the AM test. Notably, none of these effects varied with group. Positive correlations were observed between spindle density during slow-wave-sleep and AM posttest performance as well as between spindle density during non-REM sleep and AM baseline performance, showing that successful learning and retrieval both before and after sleep relates to spindle density during nap sleep. Together, these results speak for a selective beneficial impact of naps on hippocampus-dependent memories.
Collapse
Affiliation(s)
- Sara Studte
- Experimental Neuropsychology Unit, Saarland University, Germany.
| | - Emma Bridger
- Experimental Neuropsychology Unit, Saarland University, Germany.
| | - Axel Mecklinger
- Experimental Neuropsychology Unit, Saarland University, Germany.
| |
Collapse
|
13
|
Gelber RP, Redline S, Ross GW, Petrovitch H, Sonnen JA, Zarow C, Uyehara-Lock JH, Masaki KH, Launer LJ, White LR. Associations of brain lesions at autopsy with polysomnography features before death. Neurology 2014; 84:296-303. [PMID: 25503626 DOI: 10.1212/wnl.0000000000001163] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVE To determine how sleep-disordered breathing, nocturnal hypoxia, and changes in sleep architecture in the elderly may be related to the development of the neuropathologic correlates of dementia. METHODS The Honolulu-Asia Aging Study is a prospective cohort study of Japanese American men in Honolulu, HI. We examined brain lesions at autopsy (Braak stage, neurofibrillary tangle and neuritic plaque counts, microinfarcts, generalized brain atrophy, lacunar infarcts, Lewy bodies [LBs], neuronal loss and gliosis in the locus ceruleus) in 167 participants who underwent polysomnography in 1999-2000 (mean age, 84 years) and died through 2010 (mean 6.4 years to death). Polysomnography measures included the apnea-hypopnea index, duration of apnea or hypopnea, duration of hypoxemia, minimum oxygen saturation (SpO₂), duration of slow-wave sleep (SWS, non-REM stage N3), and arousals. RESULTS Sleep duration with SpO₂ <95% was associated with higher levels of microinfarcts (adjusted odds ratio [OR] 3.88, 95% confidence interval [CI] 1.10-13.76, comparing the highest to lowest quartiles of %sleep with SpO₂ <95%). Greater SWS duration was associated with less generalized atrophy (adjusted OR 0.32, 95% CI 0.10-1.03, comparing highest to lowest quartiles of %sleep in SWS). LBs were less common with greater %sleep with SpO₂ <95% (adjusted OR 0.17, 95% CI 0.04-0.78, comparing highest to lowest quartiles). Higher minimum SpO₂ during REM sleep was associated with less gliosis and neuronal loss in the locus ceruleus. Cognitive scores declined less among men with greater SWS duration. CONCLUSIONS The findings support a role for lower nocturnal oxygenation and SWS in the development of microinfarcts and brain atrophy, but not Alzheimer lesions or LBs.
Collapse
Affiliation(s)
- Rebecca P Gelber
- From the VA Pacific Islands Health Care System (R.P.G., G.W.R., H.P.), Pacific Health Research and Education Institute (R.P.G., G.W.R., H.P., J.H.U.-L., L.R.W.), Departments of Medicine (G.W.R., H.P.), Geriatric Medicine (G.W.R., H.P., K.H.M., L.R.W.), and Pathology (J.H.U.-L.), University of Hawaii John A. Burns School of Medicine, and Kuakini Medical Center (K.H.M.), Honolulu, HI; Department of Pathology (J.A.S.), University of Utah, Salt Lake City; Department of Neurology (C.Z.), Keck School of Medicine, University of Southern California, Los Angeles; Departments of Medicine and Neurology, Brigham and Women's Hospital (S.R.), Department of Medicine, Beth Israel Deaconess Medical Center (S.R.), and Harvard Medical School (S.R.), Boston, MA; and the Laboratory of Epidemiology and Population Sciences (L.J.L., L.R.W.), Intramural Research Program, National Institute on Aging, NIH, Bethesda, MD.
| | - Susan Redline
- From the VA Pacific Islands Health Care System (R.P.G., G.W.R., H.P.), Pacific Health Research and Education Institute (R.P.G., G.W.R., H.P., J.H.U.-L., L.R.W.), Departments of Medicine (G.W.R., H.P.), Geriatric Medicine (G.W.R., H.P., K.H.M., L.R.W.), and Pathology (J.H.U.-L.), University of Hawaii John A. Burns School of Medicine, and Kuakini Medical Center (K.H.M.), Honolulu, HI; Department of Pathology (J.A.S.), University of Utah, Salt Lake City; Department of Neurology (C.Z.), Keck School of Medicine, University of Southern California, Los Angeles; Departments of Medicine and Neurology, Brigham and Women's Hospital (S.R.), Department of Medicine, Beth Israel Deaconess Medical Center (S.R.), and Harvard Medical School (S.R.), Boston, MA; and the Laboratory of Epidemiology and Population Sciences (L.J.L., L.R.W.), Intramural Research Program, National Institute on Aging, NIH, Bethesda, MD
| | - G Webster Ross
- From the VA Pacific Islands Health Care System (R.P.G., G.W.R., H.P.), Pacific Health Research and Education Institute (R.P.G., G.W.R., H.P., J.H.U.-L., L.R.W.), Departments of Medicine (G.W.R., H.P.), Geriatric Medicine (G.W.R., H.P., K.H.M., L.R.W.), and Pathology (J.H.U.-L.), University of Hawaii John A. Burns School of Medicine, and Kuakini Medical Center (K.H.M.), Honolulu, HI; Department of Pathology (J.A.S.), University of Utah, Salt Lake City; Department of Neurology (C.Z.), Keck School of Medicine, University of Southern California, Los Angeles; Departments of Medicine and Neurology, Brigham and Women's Hospital (S.R.), Department of Medicine, Beth Israel Deaconess Medical Center (S.R.), and Harvard Medical School (S.R.), Boston, MA; and the Laboratory of Epidemiology and Population Sciences (L.J.L., L.R.W.), Intramural Research Program, National Institute on Aging, NIH, Bethesda, MD
| | - Helen Petrovitch
- From the VA Pacific Islands Health Care System (R.P.G., G.W.R., H.P.), Pacific Health Research and Education Institute (R.P.G., G.W.R., H.P., J.H.U.-L., L.R.W.), Departments of Medicine (G.W.R., H.P.), Geriatric Medicine (G.W.R., H.P., K.H.M., L.R.W.), and Pathology (J.H.U.-L.), University of Hawaii John A. Burns School of Medicine, and Kuakini Medical Center (K.H.M.), Honolulu, HI; Department of Pathology (J.A.S.), University of Utah, Salt Lake City; Department of Neurology (C.Z.), Keck School of Medicine, University of Southern California, Los Angeles; Departments of Medicine and Neurology, Brigham and Women's Hospital (S.R.), Department of Medicine, Beth Israel Deaconess Medical Center (S.R.), and Harvard Medical School (S.R.), Boston, MA; and the Laboratory of Epidemiology and Population Sciences (L.J.L., L.R.W.), Intramural Research Program, National Institute on Aging, NIH, Bethesda, MD
| | - Joshua A Sonnen
- From the VA Pacific Islands Health Care System (R.P.G., G.W.R., H.P.), Pacific Health Research and Education Institute (R.P.G., G.W.R., H.P., J.H.U.-L., L.R.W.), Departments of Medicine (G.W.R., H.P.), Geriatric Medicine (G.W.R., H.P., K.H.M., L.R.W.), and Pathology (J.H.U.-L.), University of Hawaii John A. Burns School of Medicine, and Kuakini Medical Center (K.H.M.), Honolulu, HI; Department of Pathology (J.A.S.), University of Utah, Salt Lake City; Department of Neurology (C.Z.), Keck School of Medicine, University of Southern California, Los Angeles; Departments of Medicine and Neurology, Brigham and Women's Hospital (S.R.), Department of Medicine, Beth Israel Deaconess Medical Center (S.R.), and Harvard Medical School (S.R.), Boston, MA; and the Laboratory of Epidemiology and Population Sciences (L.J.L., L.R.W.), Intramural Research Program, National Institute on Aging, NIH, Bethesda, MD
| | - Chris Zarow
- From the VA Pacific Islands Health Care System (R.P.G., G.W.R., H.P.), Pacific Health Research and Education Institute (R.P.G., G.W.R., H.P., J.H.U.-L., L.R.W.), Departments of Medicine (G.W.R., H.P.), Geriatric Medicine (G.W.R., H.P., K.H.M., L.R.W.), and Pathology (J.H.U.-L.), University of Hawaii John A. Burns School of Medicine, and Kuakini Medical Center (K.H.M.), Honolulu, HI; Department of Pathology (J.A.S.), University of Utah, Salt Lake City; Department of Neurology (C.Z.), Keck School of Medicine, University of Southern California, Los Angeles; Departments of Medicine and Neurology, Brigham and Women's Hospital (S.R.), Department of Medicine, Beth Israel Deaconess Medical Center (S.R.), and Harvard Medical School (S.R.), Boston, MA; and the Laboratory of Epidemiology and Population Sciences (L.J.L., L.R.W.), Intramural Research Program, National Institute on Aging, NIH, Bethesda, MD
| | - Jane H Uyehara-Lock
- From the VA Pacific Islands Health Care System (R.P.G., G.W.R., H.P.), Pacific Health Research and Education Institute (R.P.G., G.W.R., H.P., J.H.U.-L., L.R.W.), Departments of Medicine (G.W.R., H.P.), Geriatric Medicine (G.W.R., H.P., K.H.M., L.R.W.), and Pathology (J.H.U.-L.), University of Hawaii John A. Burns School of Medicine, and Kuakini Medical Center (K.H.M.), Honolulu, HI; Department of Pathology (J.A.S.), University of Utah, Salt Lake City; Department of Neurology (C.Z.), Keck School of Medicine, University of Southern California, Los Angeles; Departments of Medicine and Neurology, Brigham and Women's Hospital (S.R.), Department of Medicine, Beth Israel Deaconess Medical Center (S.R.), and Harvard Medical School (S.R.), Boston, MA; and the Laboratory of Epidemiology and Population Sciences (L.J.L., L.R.W.), Intramural Research Program, National Institute on Aging, NIH, Bethesda, MD
| | - Kamal H Masaki
- From the VA Pacific Islands Health Care System (R.P.G., G.W.R., H.P.), Pacific Health Research and Education Institute (R.P.G., G.W.R., H.P., J.H.U.-L., L.R.W.), Departments of Medicine (G.W.R., H.P.), Geriatric Medicine (G.W.R., H.P., K.H.M., L.R.W.), and Pathology (J.H.U.-L.), University of Hawaii John A. Burns School of Medicine, and Kuakini Medical Center (K.H.M.), Honolulu, HI; Department of Pathology (J.A.S.), University of Utah, Salt Lake City; Department of Neurology (C.Z.), Keck School of Medicine, University of Southern California, Los Angeles; Departments of Medicine and Neurology, Brigham and Women's Hospital (S.R.), Department of Medicine, Beth Israel Deaconess Medical Center (S.R.), and Harvard Medical School (S.R.), Boston, MA; and the Laboratory of Epidemiology and Population Sciences (L.J.L., L.R.W.), Intramural Research Program, National Institute on Aging, NIH, Bethesda, MD
| | - Lenore J Launer
- From the VA Pacific Islands Health Care System (R.P.G., G.W.R., H.P.), Pacific Health Research and Education Institute (R.P.G., G.W.R., H.P., J.H.U.-L., L.R.W.), Departments of Medicine (G.W.R., H.P.), Geriatric Medicine (G.W.R., H.P., K.H.M., L.R.W.), and Pathology (J.H.U.-L.), University of Hawaii John A. Burns School of Medicine, and Kuakini Medical Center (K.H.M.), Honolulu, HI; Department of Pathology (J.A.S.), University of Utah, Salt Lake City; Department of Neurology (C.Z.), Keck School of Medicine, University of Southern California, Los Angeles; Departments of Medicine and Neurology, Brigham and Women's Hospital (S.R.), Department of Medicine, Beth Israel Deaconess Medical Center (S.R.), and Harvard Medical School (S.R.), Boston, MA; and the Laboratory of Epidemiology and Population Sciences (L.J.L., L.R.W.), Intramural Research Program, National Institute on Aging, NIH, Bethesda, MD
| | - Lon R White
- From the VA Pacific Islands Health Care System (R.P.G., G.W.R., H.P.), Pacific Health Research and Education Institute (R.P.G., G.W.R., H.P., J.H.U.-L., L.R.W.), Departments of Medicine (G.W.R., H.P.), Geriatric Medicine (G.W.R., H.P., K.H.M., L.R.W.), and Pathology (J.H.U.-L.), University of Hawaii John A. Burns School of Medicine, and Kuakini Medical Center (K.H.M.), Honolulu, HI; Department of Pathology (J.A.S.), University of Utah, Salt Lake City; Department of Neurology (C.Z.), Keck School of Medicine, University of Southern California, Los Angeles; Departments of Medicine and Neurology, Brigham and Women's Hospital (S.R.), Department of Medicine, Beth Israel Deaconess Medical Center (S.R.), and Harvard Medical School (S.R.), Boston, MA; and the Laboratory of Epidemiology and Population Sciences (L.J.L., L.R.W.), Intramural Research Program, National Institute on Aging, NIH, Bethesda, MD
| |
Collapse
|
14
|
Schönauer M, Pawlizki A, Köck C, Gais S. Exploring the effect of sleep and reduced interference on different forms of declarative memory. Sleep 2014; 37:1995-2007. [PMID: 25325490 DOI: 10.5665/sleep.4258] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 07/03/2014] [Indexed: 11/03/2022] Open
Abstract
STUDY OBJECTIVES Many studies have found that sleep benefits declarative memory consolidation. However, fundamental questions on the specifics of this effect remain topics of discussion. It is not clear which forms of memory are affected by sleep and whether this beneficial effect is partly mediated by passive protection against interference. Moreover, a putative correlation between the structure of sleep and its memory-enhancing effects is still being discussed. DESIGN In three experiments, we tested whether sleep differentially affects various forms of declarative memory. We varied verbal content (verbal/nonverbal), item type (single/associate), and recall mode (recall/recognition, cued/free recall) to examine the effect of sleep on specific memory subtypes. We compared within-subject differences in memory consolidation between intervals including sleep, active wakefulness, or quiet meditation, which reduced external as well as internal interference and rehearsal. PARTICIPANTS Forty healthy adults aged 18-30 y, and 17 healthy adults aged 24-55 y with extensive meditation experience participated in the experiments. RESULTS All types of memory were enhanced by sleep if the sample size provided sufficient statistical power. Smaller sample sizes showed an effect of sleep if a combined measure of different declarative memory scales was used. In a condition with reduced external and internal interference, performance was equal to one with high interference. Here, memory consolidation was significantly lower than in a sleep condition. We found no correlation between sleep structure and memory consolidation. CONCLUSIONS Sleep does not preferentially consolidate a specific kind of declarative memory, but consistently promotes overall declarative memory formation. This effect is not mediated by reduced interference.
Collapse
Affiliation(s)
- Monika Schönauer
- Bernstein Center for Computational Neuroscience, Martinsried-Planegg, Germany: General and Experimental Psychology, Department of Psychology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Annedore Pawlizki
- General and Experimental Psychology, Department of Psychology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Corinna Köck
- General and Experimental Psychology, Department of Psychology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Steffen Gais
- General and Experimental Psychology, Department of Psychology, Ludwig-Maximilians-Universität München, Munich, Germany: Medical Psychology and Behavioral Neurobiology, Eberhard Karls Universität Tübingen, Tübingen, Germany
| |
Collapse
|
15
|
Lin CC, Yang CM. Evidence of sleep-facilitating effect on formation of novel semantic associations: An event-related potential (ERP) study. Neurobiol Learn Mem 2014; 116:69-78. [DOI: 10.1016/j.nlm.2014.08.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 08/18/2014] [Accepted: 08/20/2014] [Indexed: 10/24/2022]
|
16
|
The method of loci (MoL) and memory consolidation: dreaming is not MoL-like. Behav Brain Sci 2014; 36:624-5; discussion 634-59. [PMID: 24304766 DOI: 10.1017/s0140525x13001398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Certain method of loci (MoL) prerequisites--familiar, coherently ordered locations--should appear during dreaming if the latter is, in fact, elaborative memory encoding as hypothesized by Llewellyn. A review of the literature suggests that dreamed locations are neither familiar nor coherently ordered and thus unsuitable for facilitating memory in this sense. This conclusion converges with other evidence that episodic memory is dependent upon non-rapid eye movement (NREM), rather than REM, sleep.
Collapse
|
17
|
Mawdsley M, Grasby K, Talk A. The effect of sleep on item recognition and source memory recollection among shift-workers and permanent day-workers. J Sleep Res 2014; 23:538-44. [PMID: 24673876 DOI: 10.1111/jsr.12149] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2013] [Accepted: 02/23/2014] [Indexed: 11/28/2022]
Abstract
We studied the effect of sleep versus wakefulness on item recognition and source memory recollection in a sample of shift-workers and permanent day-workers. Recognition of words that were previously viewed arrayed in quadrants of a page, and recollection of the original source location of the words on the page were assessed after a 12-h retention interval that was filled with wakefulness incorporating the subjects' work-shift, or an equal period that included sleep. Both shift-workers and permanent day-workers had poorer item recognition and source memory recollection when the retention interval was spent awake rather than including sleep. Shift-workers expressed larger deficits in performance than day-workers after wakefulness. This effect was not mediated by whether the shift-workers were on a day- or night-shift at the time of the study. These results indicate that sleep is an important contributor to successful item recognition and source recollection, and that mnemonic processing in shift-workers may be especially sensitive across their work-shift.
Collapse
Affiliation(s)
- Matthew Mawdsley
- Discipline of Psychology, University of New England, Armidale, NSW, Australia
| | | | | |
Collapse
|
18
|
Bender CM, Thelen BD. Cancer and Cognitive Changes: The Complexity of the Problem. Semin Oncol Nurs 2013; 29:232-7. [DOI: 10.1016/j.soncn.2013.08.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
19
|
Palmer SD, Havelka J, van Hooff JC. Changes in recognition memory over time: an ERP investigation into vocabulary learning. PLoS One 2013; 8:e72870. [PMID: 24039813 PMCID: PMC3764170 DOI: 10.1371/journal.pone.0072870] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 07/08/2013] [Indexed: 11/19/2022] Open
Abstract
Although it seems intuitive to assume that recognition memory fades over time when information is not reinforced, some aspects of word learning may benefit from a period of consolidation. In the present study, event-related potentials (ERP) were used to examine changes in recognition memory responses to familiar and newly learned (novel) words over time. Native English speakers were taught novel words associated with English translations, and subsequently performed a Recognition Memory task in which they made old/new decisions in response to both words (trained word vs. untrained word), and novel words (trained novel word vs. untrained novel word). The Recognition task was performed 45 minutes after training (Day 1) and then repeated the following day (Day 2) with no additional training session in between. For familiar words, the late parietal old/new effect distinguished old from new items on both Day 1 and Day 2, although response to trained items was significantly weaker on Day 2. For novel words, the LPC again distinguished old from new items on both days, but the effect became significantly larger on Day 2. These data suggest that while recognition memory for familiar items may fade over time, recognition of novel items, conscious recollection in particular may benefit from a period of consolidation.
Collapse
Affiliation(s)
- Shekeila D. Palmer
- University of York, Department of Psychology, York, North Yorkshire, United Kingdom
| | - Jelena Havelka
- University of Leeds, Department of Psychology, Leeds, West Yorkshire, United Kingdom
| | | |
Collapse
|
20
|
Affiliation(s)
- Marion Inostroza
- Department of Medical Psychology and Behavioral Neurobiology and Centre for Integrative Neuroscience (CIN), University of Tübingen, 72076 Tübingen, Germany; ,
- Departamento de Psicología, Universidad de Chile, Santiago, Chile
| | - Jan Born
- Department of Medical Psychology and Behavioral Neurobiology and Centre for Integrative Neuroscience (CIN), University of Tübingen, 72076 Tübingen, Germany; ,
| |
Collapse
|
21
|
Abstract
Over more than a century of research has established the fact that sleep benefits the retention of memory. In this review we aim to comprehensively cover the field of "sleep and memory" research by providing a historical perspective on concepts and a discussion of more recent key findings. Whereas initial theories posed a passive role for sleep enhancing memories by protecting them from interfering stimuli, current theories highlight an active role for sleep in which memories undergo a process of system consolidation during sleep. Whereas older research concentrated on the role of rapid-eye-movement (REM) sleep, recent work has revealed the importance of slow-wave sleep (SWS) for memory consolidation and also enlightened some of the underlying electrophysiological, neurochemical, and genetic mechanisms, as well as developmental aspects in these processes. Specifically, newer findings characterize sleep as a brain state optimizing memory consolidation, in opposition to the waking brain being optimized for encoding of memories. Consolidation originates from reactivation of recently encoded neuronal memory representations, which occur during SWS and transform respective representations for integration into long-term memory. Ensuing REM sleep may stabilize transformed memories. While elaborated with respect to hippocampus-dependent memories, the concept of an active redistribution of memory representations from networks serving as temporary store into long-term stores might hold also for non-hippocampus-dependent memory, and even for nonneuronal, i.e., immunological memories, giving rise to the idea that the offline consolidation of memory during sleep represents a principle of long-term memory formation established in quite different physiological systems.
Collapse
Affiliation(s)
- Björn Rasch
- Division of Biopsychology, Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland.
| | | |
Collapse
|
22
|
Dang-Vu TT, Schabus M, Desseilles M, Sterpenich V, Bonjean M, Maquet P. Functional neuroimaging insights into the physiology of human sleep. Sleep 2010; 33:1589-603. [PMID: 21120121 PMCID: PMC2982729 DOI: 10.1093/sleep/33.12.1589] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Functional brain imaging has been used in humans to noninvasively investigate the neural mechanisms underlying the generation of sleep stages. On the one hand, REM sleep has been associated with the activation of the pons, thalamus, limbic areas, and temporo-occipital cortices, and the deactivation of prefrontal areas, in line with theories of REM sleep generation and dreaming properties. On the other hand, during non-REM (NREM) sleep, decreases in brain activity have been consistently found in the brainstem, thalamus, and in several cortical areas including the medial prefrontal cortex (MPFC), in agreement with a homeostatic need for brain energy recovery. Benefiting from a better temporal resolution, more recent studies have characterized the brain activations related to phasic events within specific sleep stages. In particular, they have demonstrated that NREM sleep oscillations (spindles and slow waves) are indeed associated with increases in brain activity in specific subcortical and cortical areas involved in the generation or modulation of these waves. These data highlight that, even during NREM sleep, brain activity is increased, yet regionally specific and transient. Besides refining the understanding of sleep mechanisms, functional brain imaging has also advanced the description of the functional properties of sleep. For instance, it has been shown that the sleeping brain is still able to process external information and even detect the pertinence of its content. The relationship between sleep and memory has also been refined using neuroimaging, demonstrating post-learning reactivation during sleep, as well as the reorganization of memory representation on the systems level, sometimes with long-lasting effects on subsequent memory performance. Further imaging studies should focus on clarifying the role of specific sleep patterns for the processing of external stimuli, as well as the consolidation of freshly encoded information during sleep.
Collapse
Affiliation(s)
- Thien Thanh Dang-Vu
- Cyclotron Research Center, University of Liege, Liege, Belgium
- Department of Neurology, Liege University Hospital, Liege, Belgium
| | - Manuel Schabus
- Cyclotron Research Center, University of Liege, Liege, Belgium
- Laboratory for Sleep and Consciousness Research, Department of Psychology, University of Salzburg, Salzburg, Austria
| | - Martin Desseilles
- Cyclotron Research Center, University of Liege, Liege, Belgium
- Department of Neuroscience, University of Geneva, Geneva, Switzerland
| | | | - Maxime Bonjean
- Cyclotron Research Center, University of Liege, Liege, Belgium
- Howard Hughes Medical Institute, The Salk Institute & School of Medicine, University of California, San Diego, CA
| | - Pierre Maquet
- Cyclotron Research Center, University of Liege, Liege, Belgium
- Department of Neurology, Liege University Hospital, Liege, Belgium
| |
Collapse
|
23
|
Abstract
Sleep-like behavior has been studied in honeybees before, but the relationship between sleep and memory formation has not been explored. Here we describe a new approach to address the question if sleep in bees, like in other animals, improves memory consolidation. Restrained bees were observed by a web camera, and their antennal activities were used as indicators of sleep. We found that the bees sleep more during the dark phase of the day compared with the light phase. Sleep phases were characterized by two distinct patterns of antennal activities: symmetrical activity, more prominent during the dark phase; and asymmetrical activity, more common during the light phase. Sleep-deprived bees showed rebound the following day, confirming effective deprivation of sleep. After appetitive conditioning of the bees to various olfactory stimuli, we observed their sleep. Bees conditioned to odor with sugar reward showed lesser sleep compared with bees that were exposed to either reward alone or air alone. Next, we asked whether sleep deprivation affects memory consolidation. While sleep deprivation had no effect on retention scores after odor acquisition, retention for extinction learning was significantly reduced, indicating that consolidation of extinction memory but not acquisition memory was affected by sleep deprivation.
Collapse
|
24
|
Diekelmann S, Wilhelm I, Born J. The whats and whens of sleep-dependent memory consolidation. Sleep Med Rev 2009; 13:309-21. [PMID: 19251443 DOI: 10.1016/j.smrv.2008.08.002] [Citation(s) in RCA: 341] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
25
|
Wang B, Fu XL. Gender difference in the effect of daytime sleep on declarative memory for pictures. J Zhejiang Univ Sci B 2009; 10:536-46. [PMID: 19585672 PMCID: PMC2704972 DOI: 10.1631/jzus.b0820384] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2008] [Accepted: 04/24/2009] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To investigate gender difference in the effects of daytime sleep on item and source memories, which are dissociable elements of declarative memory, and the effects of sleep on recollection and familiarity, which are two processes underlying recognition. METHODS Participants saw a series of pictures with either blue or red background, and were then given a pretest for item and source memories. Then males and females respectively were randomly assigned either to a wake or a sleep condition. In the wake condition, participants remained awake until the posttest; in the sleep condition, participants slept for 1 h until awakened and asked to remain awake until the posttest. RESULTS Daytime sleep contributed to retention of source memory rather than item memory in females, whereas males undergoing daytime sleep had a trend towards increased familiarity. For females, however, neither recollection nor familiarity appeared to be influenced by daytime sleep. CONCLUSION The mechanism underlying gender difference may be linked with different memory traces resulting from different encoding strategies, as well as with different electrophysiological changes during daytime sleep.
Collapse
Affiliation(s)
- Bo Wang
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China
- Graduate University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiao-lan Fu
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China
| |
Collapse
|