The Impact of Targeted Memory Reactivation on Memory Consolidation: A Review

Abstract Objective: Whereas numerous experimental and clinical studies suggest a complex involvement of serotonin in the regulation of anxiety, it remains to be clarified if the dominating impact of this transmitter is best described as anxiety-reducing or anxiety-promoting. The aim of this study was to assess the impact of serotonin depletion on acquisition, consolidation, and expression of conditioned fear. Methods: Male Sprague–Dawley rats were exposed to foot shocks as unconditioned stimulus and assessed with respect to freezing behaviour when re-subjected to context. Serotonin depletion was achieved by administration of a serotonin synthesis inhibitor, para-chlorophenylalanine (PCPA) (300 mg/kg daily × 3), (i) throughout the period from (and including) acquisition to (and including) expression, (ii) during acquisition but not expression, (iii) after acquisition only, and (iv) during expression only. Results: The time spent freezing was significantly reduced in animals that were serotonin-depleted during the entire period from (and including) acquisition to (and including) expression, as well as in those being serotonin-depleted during either acquisition only or expression only. In contrast, PCPA administrated immediately after acquisition, that is during memory consolidation, did not impact the expression of conditioned fear. Conclusion: Intact serotonergic neurotransmission is important for both acquisition and expression of context-conditioned fear.

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Targeted memory reactivation in REM but not SWS selectively reduces arousal responses

Communications Biology ◽

10.1038/s42003-021-01854-3 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Isabel C. Hutchison ◽

Stefania Pezzoli ◽

Maria-Efstratia Tsimpanouli ◽

Mahmoud E. A. Abdellahi ◽

Penelope A. Lewis

Keyword(s):

Slow Wave Sleep ◽

Sleep Stage ◽

Emotional Memory ◽

Rapid Eye Movement Sleep ◽

Emotional Experiences ◽

Memory Reactivation ◽

Emotional Memories ◽

The Impact ◽

Subjective Arousal ◽

Spontaneous Reactivation

AbstractA growing body of evidence suggests that sleep can help to decouple the memory of emotional experiences from their associated affective charge. This process is thought to rely on the spontaneous reactivation of emotional memories during sleep, though it is still unclear which sleep stage is optimal for such reactivation. We examined this question by explicitly manipulating memory reactivation in both rapid-eye movement sleep (REM) and slow-wave sleep (SWS) using targeted memory reactivation (TMR) and testing the impact of this manipulation on habituation of subjective arousal responses across a night. Our results show that TMR during REM, but not SWS significantly decreased subjective arousal, and this effect is driven by the more negative stimuli. These results support one aspect of the sleep to forget, sleep to remember (SFSR) hypothesis which proposes that emotional memory reactivation during REM sleep underlies sleep-dependent habituation.

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Methods for Assessment of Memory Reactivation

Neural Computation ◽

10.1162/neco_a_01090 ◽

2018 ◽

Vol 30 (8) ◽

pp. 2175-2209 ◽

Cited By ~ 5

Author(s):

Shizhao Liu ◽

Andres D. Grosmark ◽

Zhe Chen

Keyword(s):

Statistical Methods ◽

Memory Consolidation ◽

Slow Wave Sleep ◽

Brain Regions ◽

Weighted Distance ◽

Memory Reactivation ◽

Statistical Dependency ◽

Stored Information ◽

Robust Statistical Methods ◽

Population Decoding

It has been suggested that reactivation of previously acquired experiences or stored information in declarative memories in the hippocampus and neocortex contributes to memory consolidation and learning. Understanding memory consolidation depends crucially on the development of robust statistical methods for assessing memory reactivation. To date, several statistical methods have seen established for assessing memory reactivation based on bursts of ensemble neural spike activity during offline states. Using population-decoding methods, we propose a new statistical metric, the weighted distance correlation, to assess hippocampal memory reactivation (i.e., spatial memory replay) during quiet wakefulness and slow-wave sleep. The new metric can be combined with an unsupervised population decoding analysis, which is invariant to latent state labeling and allows us to detect statistical dependency beyond linearity in memory traces. We validate the new metric using two rat hippocampal recordings in spatial navigation tasks. Our proposed analysis framework may have a broader impact on assessing memory reactivations in other brain regions under different behavioral tasks.

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0248 STUDYING SLEEP STAGE SPECIFICITY OF EMOTIONAL MEMORY CONSOLIDATION USING TARGETED MEMORY REACTIVATION

SLEEP ◽

10.1093/sleepj/zsx050.247 ◽

2017 ◽

Vol 40 (suppl_1) ◽

pp. A91-A91

Author(s):

C Yuksel

Keyword(s):

Memory Consolidation ◽

Sleep Stage ◽

Emotional Memory ◽

Memory Reactivation ◽

Stage Specificity

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Peripheral and central CB1 cannabinoid receptors control stress-induced impairment of memory consolidation

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1525066113 ◽

2016 ◽

Vol 113 (35) ◽

pp. 9904-9909 ◽

Cited By ~ 32

Author(s):

Arnau Busquets-Garcia ◽

Maria Gomis-González ◽

Raj Kamal Srivastava ◽

Laura Cutando ◽

Antonio Ortega-Alvaro ◽

...

Keyword(s):

Memory Consolidation ◽

Cannabinoid Receptors ◽

Recognition Task ◽

Underlying Mechanism ◽

Stressful Events ◽

Specific Cell ◽

Cb1 Receptors ◽

Emotional Memories ◽

Stress Dependent ◽

The Impact

Stressful events can generate emotional memories linked to the traumatic incident, but they also can impair the formation of nonemotional memories. Although the impact of stress on emotional memories is well studied, much less is known about the influence of the emotional state on the formation of nonemotional memories. We used the novel object-recognition task as a model of nonemotional memory in mice to investigate the underlying mechanism of the deleterious effect of stress on memory consolidation. Systemic, hippocampal, and peripheral blockade of cannabinoid type-1 (CB1) receptors abolished the stress-induced memory impairment. Genetic deletion and rescue of CB1 receptors in specific cell types revealed that the CB1 receptor population specifically in dopamine β-hydroxylase (DBH)-expressing cells is both necessary and sufficient for stress-induced impairment of memory consolidation, but CB1 receptors present in other neuronal populations are not involved. Strikingly, pharmacological manipulations in mice expressing CB1 receptors exclusively in DBH+ cells revealed that both hippocampal and peripheral receptors mediate the impact of stress on memory consolidation. Thus, CB1 receptors on adrenergic and noradrenergic cells provide previously unrecognized cross-talk between central and peripheral mechanisms in the stress-dependent regulation of nonemotional memory consolidation, suggesting new potential avenues for the treatment of cognitive aspects on stress-related disorders.

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Applying time series analyses on continuous accelerometry data – a clinical example in older adults with and without cognitive impairment

10.1101/2020.03.24.20042226 ◽

2020 ◽

Author(s):

Torsten Rackoll ◽

Konrad Neumann ◽

Sven Passmann ◽

Ulrike Grittner ◽

Nadine Külzow ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Brain Stimulation ◽

Memory Consolidation ◽

Activity Patterns ◽

Accelerometer Data ◽

Activity Data ◽

Link Type ◽

Early Afternoon ◽

The Impact

AbstractIntroductionCurrent analysis approaches of accelerometry data use sum score measures which do not provide insight in activity patterns over 24 hours, and thus do not adequately depict circadian activity patterns. Here, we used a functional approach to analyze accelerometer data that models activity pattern and circadian rhythm. As a test case, we demonstrated its application in patients with mild cognitive impairment (MCI) and age-matched healthy older volunteers (HOV). Moreover, we assessed the impact of chronotype on distribution of activity data.MethodsData of two studies were pooled for this analysis. Following baseline cognitive assessment participants were provided with accelerometers for seven consecutive days. A function on scalar regression (FoSR) approach was used to analyze 24 hours accelerometer data. In a second step, analyses were controlled for chronotype using the German version of the morningness-eveningness questionnaire (d-MEQ).ResultsInformation on 47 HOV (mean age 66 SD 6 years) and 13 patients with MCI (mean age 69, SD 8 years) were available for this analysis. MCI patients displayed slightly higher activity in the morning hours as compared to HOV (maximum relative activity at 7:35 am: 75.6%, 95% CI 2.6 to 200.4%, p = 0.031). After controlling for d-MEQ, disturbed activity patterns were found in MCI of intermediate or evening chronotype, compared to HOV, i.e., MCI presented with higher activities in the morning hours (peak at 8:40 am: 357.6%, 95% CI 92.9 to 985.1, p < 0.001) and early afternoon hours (peak at 1:40 pm: 401.8%, 95% CI 63.9 to 1436.4, p < 0.001).DiscussionUsing a novel approach of FoSR, we found timeframes with higher activity levels in MCI patients compared to HOV which were not evident if sum scores of amount of activity were used. In addition, we found that previously described activity patterns as a function of chronotype swere altered in MCI patients, possibly indicating that changes in circadian rhythmicity in neurodegenerative disease are detectable using easy-to-administer accelerometry.Clinical TrialsEffects of Brain Stimulation During Nocturnal Sleep on Memory Consolidation in Patients With Mild Cognitive Impairments, https://clinicaltrials.gov/ct2/show/NCT01782391?term=NCT01782391&rank=1,ClinicalTrial.gov identifier: NCT01782391Effects of Brain Stimulation During a Daytime Nap on Memory Consolidation in Patients With Mild Cognitive Impairment,https://clinicaltrials.gov/ct2/show/NCT01782365?term=NCT01782365&rank=1,ClinicalTrial.gov identifier: NCT01782365

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Cued Memory Reactivation: A Tool to Manipulate Memory Consolidation During Sleep

Handbook of Sleep Research - Handbook of Behavioral Neuroscience ◽

10.1016/b978-0-12-813743-7.00031-1 ◽

2019 ◽

pp. 471-488 ◽

Cited By ~ 1

Author(s):

Jens G. Klinzing ◽

Susanne Diekelmann

Keyword(s):

Memory Consolidation ◽

Memory Reactivation

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0099 The Effects of Sleep on the Consolidation of Fearful Memories

SLEEP ◽

10.1093/sleep/zsaa056.097 ◽

2020 ◽

Vol 43 (Supplement_1) ◽

pp. A39-A40

Author(s):

M Arsic ◽

L Heiss ◽

A M Chambers

Keyword(s):

Memory Consolidation ◽

Emotional Memory ◽

Neutral Condition ◽

Emotion Induction ◽

Induction Procedure ◽

Main Effect ◽

Before And After ◽

Real World Learning ◽

Emotional Events ◽

The Impact

Abstract Introduction Previous research has found that emotionally intense stimuli are better remembered than neutral stimuli, especially after a period of sleep. However, few studies have examined memory for experienced emotional events, especially fearful ones. The purpose of the current study was to investigate the impact of sleep on memory consolidation using a fearful emotion induction task. Methods Thirty-three young adults (18.94±1.06 years; 64% female) were randomly assigned to either a fearful or neutral emotion induction condition. Participants were induced into their assigned emotion by visualizing each of eight emotion-congruent scenarios while corresponding music played in the background. Emotional state was measured using the Affect Grid before and after the emotion induction procedure. Twelve hours later, spanning either a day of wakefulness (wake group) or night of sleep (sleep group), participants were asked to recall the previously presented scenarios. Results A 2 x 2 ANOVA examined differences in the number of scenarios recalled between the conditions. A significant main effect of sleep was found, F(1,29)=8.41, p=.007, η 2p=.23, reflecting better recall in the sleep (3.21±1.78) vs. the wake group (1.79±1.72). There was also a main effect of emotion, F(1,29)=22.17, p<.001, η 2p=.43, reflecting better recall in the fear (3.58±1.54) vs. the neutral condition (1.29±1.44). However, there was no interaction. Results were similar for the number of details recalled between the conditions. The sleep group (12.74±9.09) recalled more details than the wake group (5.50±5.81), F(1,29)=8.05, p=.008, η 2p=.22. More details were also recalled in the fear condition (13.16±8.73) than the neutral condition (4.93±5.77), F(1,29)=10.54, p=.003, η 2p=.27. There was again no interaction. Conclusion Results demonstrate that both sleep and fearful emotion facilitate memory consolidation. This work both supports and extends existing research by examining emotional memory consolidation through the manipulation of experienced events, which may more closely approximate real world learning than previous methods. Support N/A

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