Precise Slow Oscillation–Spindle Coupling Promotes Memory Consolidation in Younger and Older Adults

Abstract The dialogue between cortex and hippocampus is known to be crucial for sleep-dependent memory consolidation. During slow wave sleep, memory replay depends on slow oscillation (SO) and spindles in the (neo)cortex and sharp wave-ripples (SWRs) in the hippocampus. The mechanisms underlying interaction of these rhythms are poorly understood. We examined the interaction between cortical SO and hippocampal SWRs in a model of the hippocampo–cortico–thalamic network and compared the results with human intracranial recordings during sleep. We observed that ripple occurrence peaked following the onset of an Up-state of SO and that cortical input to hippocampus was crucial to maintain this relationship. A small fraction of ripples occurred during the Down-state and controlled initiation of the next Up-state. We observed that the effect of ripple depends on its precise timing, which supports the idea that ripples occurring at different phases of SO might serve different functions, particularly in the context of encoding the new and reactivation of the old memories during memory consolidation. The study revealed complex bidirectional interaction of SWRs and SO in which early hippocampal ripples influence transitions to Up-state, while cortical Up-states control occurrence of the later ripples, which in turn influence transition to Down-state.

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Memory consolidation effects on memory stabilization and item integration in older adults

Psychonomic Bulletin & Review ◽

10.3758/s13423-016-1197-0 ◽

2016 ◽

Vol 24 (4) ◽

pp. 1032-1039 ◽

Cited By ~ 3

Author(s):

Helen Brown ◽

Elizabeth A. Maylor

Keyword(s):

Older Adults ◽

Memory Consolidation

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Enhancing Memory Consolidation through Slow Oscillation and Spindle Synchronization

Journal of Neuroscience ◽

10.1523/jneurosci.2512-17.2017 ◽

2017 ◽

Vol 37 (48) ◽

pp. 11517-11519 ◽

Cited By ~ 1

Author(s):

Sara Y. Kim ◽

Enmanuelle Pardilla-Delgado ◽

Sara E. Alger

Keyword(s):

Memory Consolidation ◽

Slow Oscillation

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0101 Episodic Future Thinking Triggers Age-Related Differences in Spindles and Slow Oscillations

SLEEP ◽

10.1093/sleep/zsaa056.099 ◽

2020 ◽

Vol 43 (Supplement_1) ◽

pp. A40-A40

Author(s):

J Diaz ◽

P Fillmore ◽

C Gao ◽

M K Scullin

Keyword(s):

Older Adults ◽

Young Adults ◽

Memory Consolidation ◽

Word Count ◽

Future Thinking ◽

Future Tense ◽

Slow Oscillations ◽

The Past ◽

Age Related ◽

The Future

Abstract Introduction In young adults, sleep spindles are theorized to represent memory consolidation. Spindle density may be especially prominent when young adults encode information that has future relevance. Older adults, on the other hand, show reduced capacity for future thinking and deficits in sleep-dependent memory consolidation. To advance these literatures, we investigated whether the process of mentally simulating the future (versus remembering the past) was associated with subsequent alterations to sleep microarchitecture in young and older adults. Methods 64 healthy adults aged 18–84 completed a polysomnography adaptation night followed by two in-laboratory experimental nights. On both nights, participants completed the Modified Future Crovitz Test (MFCT) in which they mentally simulated only future events or remembered only past events (night order counterbalanced). To quantify the extent of future/past thinking, we conducted linguistics analyses on tense (future/past) using LIWC 2015 software. Results On the future-thinking night, young adults with greater future-tense MFCT scores showed significantly greater spindle density across frontal, midline, and central sites (r=.42 to r=.51), even when controlling for age, gender, and total word count (all ps < .01). The opposite was true for middle-to-older aged adults; greater future-tense MFCT scores were associated with less spindle density across midline and central sites after controlling for age, gender, and word count (r=-.44 to r=-.46, ps<.05). However, while spindle density decreased, frontal slow oscillations increased in older adults with greater future-tense MFCT scores (r=.39, p<.05). On the past-thinking night, spindle density and slow oscillations were unrelated to past-tense or future-tense MFCT scores for either age group. Conclusion Age-related deficits in memory consolidation may be due to impaired tagging of information as having future relevance, or impaired physiological responses during sleep to wake-based tagging. Addressing encoding—spindle interactions may inform why cognitive functioning declines in some adults more than others. Support Sleep Research Society Foundation

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Cerebral Activation During Initial Motor Learning Forecasts Subsequent Sleep-Facilitated Memory Consolidation in Older Adults

Cerebral Cortex ◽

10.1093/cercor/bhv347 ◽

2016 ◽

pp. bhv347 ◽

Cited By ~ 12

Author(s):

Bradley R. King ◽

Philippe Saucier ◽

Genevieve Albouy ◽

Stuart M. Fogel ◽

Jost-Julian Rumpf ◽

...

Keyword(s):

Older Adults ◽

Motor Learning ◽

Memory Consolidation ◽

Cerebral Activation

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0696 Memory Consolidation and Cerebral Oxygenation during Afternoon Naps in Older Adults with Amnestic Mild Cognitive Impairment

SLEEP ◽

10.1093/sleep/zsy061.695 ◽

2018 ◽

Vol 41 (suppl_1) ◽

pp. A258-A259

Author(s):

B W Carlson ◽

K R Jones ◽

M A Craft ◽

J R Carlson ◽

K Deardeuff ◽

...

Keyword(s):

Older Adults ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Memory Consolidation ◽

Cerebral Oxygenation ◽

Amnestic Mild Cognitive Impairment

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Slow oscillation-spindle coupling impairs emotional memory consolidation following stress

10.1101/2020.06.08.140350 ◽

2020 ◽

Author(s):

Dan Denis ◽

Sara Y. Kim ◽

Sarah M. Kark ◽

Ryan T. Daley ◽

Elizabeth A. Kensinger ◽

...

Keyword(s):

Memory Consolidation ◽

Slow Wave Sleep ◽

Sleep Stage ◽

Emotional Memory ◽

Slow Oscillation ◽

Stress Group ◽

Line Drawings ◽

Comparable Control ◽

Low Cortisol ◽

And Control

AbstractSleep and stress have both been shown to enhance emotional memory consolidation. They also interact, with the largest benefit of sleep on emotional memory being seen when stress occurs either shortly before or after memory encoding. Slow wave sleep (SWS) is believed to be critical for episodic memory consolidation, facilitated by the coupling of slow oscillations and sleep spindles. However, prior work in humans has only demonstrated slow oscillation-spindle coupling to be associated with consolidation of neutral information in non-stressed participants. Whether coupling interacts with stress to facilitate emotional memory consolidation is unknown. To address this exploratory question, we reanalyzed an existing dataset of N=64 individuals. Participants underwent a psychosocial stressor (n=32) or comparable control (n=32) prior to the encoding of 150 line drawings of neutral, positive, and negative images. All participants then slept overnight with polysomnographic recordings. The next day, they were given a surprise memory test. In the stress group, percentage of time spent in SWS was positively correlated with memory for images of all valences (all r>.35, p<.043). Results were primarily driven by those who showed a high cortisol response to the stressor (all r>.65, p<.007), compared to low cortisol responders (all r<.31, all p>.25). However, the amount of slow oscillation-spindle coupling during SWS was negatively associated with neutral (r= −.45, p=.01) and emotional (r=−.66, p<.001) memory in the stress group. The negative association with emotional memory was significantly stronger than for neutral memory (Meng z=2.04, p=.04). Between stress and control groups, there were no differences in any of the sleep measures assessed. These results highlight the importance of considering sleep microarchitecture events in addition to overall sleep stage time and suggests that stress may alter the relationship between SWS and memory consolidation.

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Multisession transcranial direct current stimulation facilitates verbal learning and memory consolidation in young and older adults

Brain and Language ◽

10.1016/j.bandl.2020.104788 ◽

2020 ◽

Vol 205 ◽

pp. 104788

Author(s):

Garon Perceval ◽

Andrew K. Martin ◽

David A. Copland ◽

Matti Laine ◽

Marcus Meinzer

Keyword(s):

Older Adults ◽

Learning And Memory ◽

Direct Current ◽

Memory Consolidation ◽

Transcranial Direct Current Stimulation ◽

Verbal Learning ◽

Direct Current Stimulation

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0119 The Role of Aging and Working Memory in Emotional-Long Term Memory Formation

SLEEP ◽

10.1093/sleep/zsaa056.117 ◽

2020 ◽

Vol 43 (Supplement_1) ◽

pp. A47-A47

Author(s):

N Sattari ◽

L Whitehurst ◽

K Vinces ◽

S Mednick

Keyword(s):

Older Adults ◽

Working Memory ◽

Memory Consolidation ◽

Memory Formation ◽

Long Term Memory ◽

Term Memory ◽

Memory Improvement ◽

Condition Interaction

Abstract Introduction It is widely accepted that “offline” processes during sleep contributes to memory. Working Memory (WM) capacity, which reflects “online” memory processing, is an important factor influencing cognitive functioning, which declines with age. In younger individuals, a positive association is reported between WM-capacity and declarative memory improvement. Methods We examined the relation between WM and long-term memory consolidation, among younger [N=105, 18-25yr] and older adults (N=119, 60-85yr). Subjects completed an OSPAN WM task, encoded a Word-Paired Association (WPA) task in the morning (Test1), and were tested on the WPA in the afternoon (Test2) after a 90-minute polysomnographically-recorded nap or wake. Half of the subjects were exposed to negatively valenced word-pairs (EWPA) while the other half were exposed to neutral word-pairs (NWPA). Subjects rated valence of the word-pairs at Test1 and Test2. We compared the four groups (young-EWPA, young-NWPA, old-EWPA and old-NWPA) on WM and WPA in both wake and sleep. Results In both wake and sleep, in the WPA, ageXword-condition interaction was found (p=.004). Post-hoc analysis revealed that in wake, younger-EWPA had higher performance (p=.03) than younger-NWPA, however, older-EWPA had lower performance (p=.03) than older-NWPA. Additionally, we found an ageXword-condition interaction whereby youngers showed no change in ratings, while older adults rated word-pairs more positively both in wake (p=.03) and sleep (p=.002) at Test 2. Youngers had higher WM performance (p=.007), also their WM performance was positively associated with WPA both for Neutral (p=.03) and Emotional (p=.01). WM and WPA among older adults was not related. In younger-EWPA, Stage2-sleep-minutes was positively associated to WPA improvement (p=.03) where this association was negative among older-EWPA (p=.02). In older-NWPA, Stage2-sleep-minutes was positively associated with WPA (p=.004). Conclusion Our findings indicate an association between WM and emotionally-salient memory formation that is modulated by age. Older adults, but not younger, showed the emotional bias previously reported. WM was higher in younger adults related to memory improvement. Stage2-sleep was related to memory improvement in both groups, but in opposite directions. In sum, the role of sleep in memory consolidation changes with aging and WM may play a role in this process. Support Fenn et al.,2012

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