Sleep reduces false memory in healthy older adults

Relation between Deese-Roediger-Mcdermott recall measures of false memory and the fading affect bias

The fading affect bias (FAB) is the faster fading of unpleasant affect than pleasant affect for autobiographical event memories, and it is considered a healthy coping mechanism because it is positively related to healthy measures (e.g., self-esteem and positive PANAS), whereas it is negatively related to unhealthy measures (e.g., psychological distress and negative PANAS). Some researchers suggest that Deese-Roediger McDermott (DRM) critical lure false memories for words are conceptually equivalent to false memories for autobiographical event memories, which has not been examined. Based on the finding that false autobiographical event memories negatively predict FAB, the current study tested if false DRM word memories would negatively predict FAB for autobiographical event memories, which would demonstrate support for the conceptual equivalence of DRM memories and autobiographical event memories. We found that three measures of false word recall positively predicted FAB, which is a result that is contrary to prior findings and the contention that DRM false memories for words are conceptually the same as autobiographical event memories.

Impact of sleep deprivation on stress levels and cognitive performance in young and middle-aged adults at a Medical University in Ajman, UAE

BACKGROUND

Inadequate sleep is a widespread public health concern, impacting physical and mental health, as well as cognitive well-being. This study explores the link between sleep quality, the inflammatory marker interleukin-6 (IL-6), and cognitive function in two age groups (18-25 years and 35 years and above) at Gulf Medical University.

MATERIALS AND METHODS

Sleep quality was assessed using the Pittsburgh questionnaire, and salivary IL-6 levels were measured. Cognitive function was evaluated using the National Aeronautics and Space Administration-Psychomotor Vigilance Test (NASA-PVT), focusing on mean reaction time (RT), lapses, fastest 10% RT, and slowest 10% RT. Descriptive and inferential statistics were used to analyze the data. The descriptive statistics used were frequency, percentage mean, and standard deviation (SD). The inferential statistics used was the unpaired t-test. The level of significance was taken as P ≤ 0.05. Statistical Package for the Social Sciences (SPSS) 28 was used to analyze the data.

RESULTS

Approximately 75% of young adults and 80% of middle-aged adults reported good sleep quality. Sleep disturbances were reported by 65% of young adults and 95% of middle-aged adults. In both age groups, individuals with poor sleep exhibited higher IL-6 levels, but all IL-6 values remained within the reference range. NASA-PVT results indicated that individuals with poor sleep had higher mean RT and lapses compared to those with good sleep. In the older age group, both mean RT and lapses were higher than in the younger group, suggesting potential age-related effects on psychomotor vigilance.

CONCLUSION

Our findings suggest a connection between poor sleep quality, elevated IL-6 levels, and impaired cognitive performance.

Consolidation without intention: Sleep strengthens veridical and gist representations of information after incidental encoding

Sleep strengthens declarative memory, but research investigating the effect of sleep on memory for information that is not explicitly studied for a test is sparse. In two experiments, we investigated the effect of sleep on gist-based and veridical representations of incidentally encoded information. Participants rated words from Deese-Roediger-McDermott (DRM) lists in either a deep or shallow encoding task and completed a surprise memory test after either sleep or wake. In Experiment 1, words were presented in lists, in order of descending associativity with the unpresented critical lure. Memory for list words and critical lures in both encoding tasks was stronger after sleep than wake, suggesting that sleep consolidated gist-based memory. In Experiment 2, the same words were presented in a random order across the experiment to minimize gist-based processing. Sleep strengthened veridical memory for list words following deep, but not shallow, encoding and did not affect critical lures. These results suggest sleep consolidates gist and veridical representations of information after incidental encoding, and that sleep-dependent consolidation processes may depend on processes at encoding, such as overlapping context and the strength of veridical memory traces.

Associations between objectively measured sleep parameters and cognition in healthy older adults: A meta-analysis

Multiple studies have examined associations between sleep and cognition in older adults, but a majority of these depend on self-reports on sleep and utilize cognitive tests that assess overall cognitive function. The current meta-analysis involved 72 independent studies and sought to quantify associations between objectively measured sleep parameters and cognitive performance in healthy older adults. Both sleep macrostructure (e.g., sleep duration, continuity, and stages) and microstructure (e.g., slow wave activity and spindle activity) were evaluated. For macrostructure, lower restlessness at night was associated with better memory performance (r = 0.43, p = 0.02), while lower sleep onset latency was associated with better executive functioning (r = 0.28, p = 0.03). Greater relative amount of N2 and REM sleep, but not N3, positively correlated with cognitive performance. The association between microstructure and cognition in older adults was marginally significant. This relationship was moderated by age (z = 0.07, p < 0.01), education (z = 0.26, p = 0.03), and percentage of female participants (z = 0.01, p < 0.01). The current meta-analysis emphasizes the importance of considering objective sleep measures to understand the relationship between sleep and cognition in healthy older adults. These results also form a base from which researchers using wearable sleep technology and measuring behavior through computerized testing tools can evaluate their findings.

Sleep Modulates Emotional Effect on False Memory

Background

Whereas sleep and emotion are important factors affecting false memory, there is a lack of empirical research on the interaction effect of sleep and emotion on false memory. Moreover, it should be investigated further that how the effects of emotion on false memory varies from presenting emotional content to eliciting emotional state.

Objective

To examine how sleep and varying emotional context influence false memories. We predicted that sleep and emotion would interactively affect false memory when participants are presented with negative words in a learning session (Experiment 1) or when their emotional state is induced before a learning session (Experiment 2).

Design

We used the Deese-Roediger-McDermott (DRM) task. Emotional words were used to elicit emotion during learning in Experiment 1 and video clips were used to induce a particular mood state before learning in Experiment 2. Participants were divided into a "sleep group" and a "wake group" and completed an initial learning session either in the evening or in the morning respectively. After a learning session, participants in the sleep group slept at night as usual and completed a recognition test in the morning, while participants in the wake group stayed awake during the daytime and completed their recognition test in the evening. All participants completed a recognition test after the same period of time.

Results

In Experiment 1, the wake group falsely recognized more negative critical lure words than neutral ones, but no such difference existed in the sleep group, suggesting that sleep modulated the emotional effect on false memory. In Experiment 2, participants in either a positive or negative mood state showed more false recognition than those in a neutral state. There was no such difference in the wake group. We conclude that sleep and emotion interactively affect false memory.

Memory decay distinguishes subtypes of gist

Memories are thought to become more gist-like over time. Multiple related memories might form generalized memory representations, losing specific details but enhancing or retaining gist. The time course within which gist memory emerges, however, is the subject of less consensus. To address this question, we focused our design on four kinds of gist: inferential gist (relations extracted across non-contiguous events), statistical learning (regularities extracted from a series), summary gist (a theme abstracted from a temporally contiguous series of items), and category gist (characterization of a stimulus at a higher level in the semantic hierarchy). Seventy participants completed memory encoding tasks addressing these types of gist and corresponding retrieval tasks the same evening, the morning after, and one week later, as well as an MRI at a later time point. We found little evidence that gist slowly emerges over time or that gist traces are more resistant to forgetting than detail traces. Instead, we found that initial gist memory shortly after encoding was either retained over time or decayed. Inferential gist and statistical learning were retained over a week, whereas memory for category and summary gist decayed. We discuss several interpretations for differences between these two subtypes of gist. Individual differences in REM or slow-wave sleep and hippocampal volumes did not predict changes in memory for these four kinds of gist in a healthy young adult population.

Associations Between Sleep Quality and Health Span: A Prospective Cohort Study Based on 328,850 UK Biobank Participants

OBJECTIVE

To examine the associations between sleep quality and health span using a prospective cohort design based on the UK Biobank (UKB).

MATERIALS AND METHODS

This longitudinal cohort study enrolled 328,850 participants aged between 37 and 73 years from UKB to examine the associations between sleep quality and risk of terminated health span. End of health span was defined by eight events strongly associated with longevity (cancer, death, congestive heart failure, myocardial infarction, chronic obstructive pulmonary disease, stroke, dementia, and diabetes), and a sleep score was generated according to five sleep behavioral factors (sleep duration, chronotype, sleeplessness, daytime sleepiness, and snoring) to characterize sleep quality. The hazard ratio (HR) and 95% confidence intervals (CIs) were calculated by multivariate-adjusted Cox proportional hazards model. Moreover, we calculated population attributable risk percentage (PAR%) to reflect the public health significance of healthy sleep quality.

RESULTS

Compared with poor sleep quality, participants with healthy sleep quality had a 15% (HR: 0.85, 95% CI: 0.81-0.88) reduced risk of terminated health span, and those of less-healthy sleep quality had a 12% (HR: 0.88, 95% CI: 0.85-0.92) reduced risk. Linear trend results indicated that the risk of terminated health span decreased by 4% for every additional sleep score. Nearly 15% health span termination events in this cohort would have been prevented if a healthy sleep behavior pattern was adhered to (PAR%: 15.30, 95% CI: 12.58-17.93).

CONCLUSION

Healthy sleep quality was associated with a reduced risk of premature end of health span, suggesting healthy sleep behavior may extend health span. However, further studies are suggested for confirmation of causality and potential mechanism.

How do children with autism spectrum disorder form gist memory during sleep? A study of slow oscillation-spindle coupling

Sleep is assumed to support memory through an active systems consolidation process that does not only strengthen newly encoded representations but also facilitates the formation of more abstract gist memories. Studies in humans and rodents indicate a key role of the precise temporal coupling of sleep slow oscillations (SO) and spindles in this process. The present study aimed at bolstering these findings in typically developing (TD) children, and at dissecting particularities in SO-spindle coupling underlying signs of enhanced gist memory formation during sleep found in a foregoing study in children with autism spectrum disorder (ASD) without intellectual impairment. Sleep data from 19 boys with ASD and 20 TD boys (9-12 years) were analyzed. Children performed a picture-recognition task and the Deese-Roediger-McDermott (DRM) task before nocturnal sleep (encoding) and in the next morning (retrieval). Sleep-dependent benefits for visual-recognition memory were comparable between groups but were greater for gist abstraction (recall of DRM critical lure words) in ASD than TD children. Both groups showed a closely comparable SO-spindle coupling, with fast spindle activity nesting in SO-upstates, suggesting that a key mechanism of memory processing during sleep is fully functioning already at childhood. Picture-recognition at retrieval after sleep was positively correlated to frontocortical SO-fast-spindle coupling in TD children, and less in ASD children. Critical lure recall did not correlate with SO-spindle coupling in TD children but showed a negative correlation (r = -.64, p = .003) with parietal SO-fast-spindle coupling in ASD children, suggesting other mechanisms specifically conveying gist abstraction, that may even compete with SO-spindle coupling.

Investigation of the relationships between sleep behaviors and risk of healthspan termination: a prospective cohort study based on 323,373 UK-Biobank participants

OBJECTIVES

To examine the associations between four sleep behaviors and the risk of healthspan termination.

METHODS

This study included 323,373 participants, free of terminated healthspan at baseline, from the UK-Biobank (UKB). We applied multivariable-adjusted Cox regression models to estimate the risk of terminated healthspan based on four sleep behaviors (insomnia/sleeplessness, napping, daytime sleepiness, and difficulty getting up from bed), which were self-reported and measured on Likert scales from "usually" to "never/rarely" experiences. In this study, healthspan was defined based on eight events that are strongly associated with longevity (congestive heart failure, myocardial infarction, chronic obstructive pulmonary disease, stroke, dementia, diabetes, cancer, and death).

RESULTS

Participants who reported the following unhealthy sleep behaviors had a significantly higher risk of terminated healthspan: "usually experience sleeplessness/insomnia" (HR = 1.05, 95% CI: 1.03-1.07; P < 0.001); "usually nap" (HR = 1.22, 95% CI: 1.18-1.26; P < 0.01); "excessive daytime sleepiness" (HR = 1.25, 95% CI: 1.19-1.32; P < 0.001); and "difficult getting up from bed" (HR = 1.08, 95% CI: 1.05-1.10; P < 0.001). The corresponding population attributable risk percentage (PAR%) indicated that about 7% of healthspan termination in this cohort would have been eliminated if all participants had healthy sleep behaviors.

CONCLUSION

Participants who reported "usually experience sleeplessness/insomnia," "usually nap," "excessive daytime sleepiness," and "difficult getting up from bed" had increased risk of shortened healthspan. Therefore, adherence to healthy sleep behavior is significant for the extension of healthspan.

The different roles of sleep on false memory formation between young and older adults

Aging is accompanied by an increase in the probability of false memory. However, what role sleep plays in the age effect in false memory is less understood. Our study utilized a simplified conjoint recognition (SCR)-based Deese-Roediger-McDermott (DRM) paradigm to investigate the role of sleep on false memory in young and older adults. The results showed that sleep effect in false memory was modulated by age, manifested as sleep increased young adults' falsely recognized critical lures, while it reduced older adults'. In addition, in a more fine-grained analysis, the results of multinomial processing tree (MPT) modeling further revealed that young adults were more likely to retrieve memory based on gist traces than older adults, and young adults were more susceptible to guess a probe as "old" than older adults in the sleep condition. Combined findings from the number and ratio of falsely recognized critical lures and the MPT modeling, the current study suggested that sleep might increase young adults' false memory via gist extraction, while it decreased older adults' false memory via verbatim trace consolidation. The study contributes to a comprehensive view on the age-by-sleep effect on false recognition, with the segregation of cognitive components of verbatim memory, gist memory, and response bias.

Is Sleep Disruption a Cause or Consequence of Alzheimer's Disease? Reviewing Its Possible Role as a Biomarker

In recent years, the idea that sleep is critical for cognitive processing has gained strength. Alzheimer's disease (AD) is the most common form of dementia worldwide and presents a high prevalence of sleep disturbances. However, it is difficult to establish causal relations, since a vicious circle emerges between different aspects of the disease. Nowadays, we know that sleep is crucial to consolidate memory and to remove the excess of beta-amyloid and hyperphosphorilated tau accumulated in AD patients' brains. In this review, we discuss how sleep disturbances often precede in years some pathological traits, as well as cognitive decline, in AD. We describe the relevance of sleep to memory consolidation, focusing on changes in sleep patterns in AD in contrast to normal aging. We also analyze whether sleep alterations could be useful biomarkers to predict the risk of developing AD and we compile some sleep-related proposed biomarkers. The relevance of the analysis of the sleep microstructure is highlighted to detect specific oscillatory patterns that could be useful as AD biomarkers.

When does sleep affect veridical and false memory consolidation? A meta-analysis

It is widely accepted that sleep aids in the encoding, consolidation, and retrieval processes involved in memory processing; however, the conditions under which sleep influences memory may be substantially constrained. In a meta-analysis, we examined the effects that sleep has on both veridical (accurate) and false memory consolidation, in studies using the Deese/Roediger-McDermott (DRM) paradigm for memory of thematically related words. The meta-analysis revealed that, whereas there was no overall effect of sleep on either accurate or false memories, the effect of sleep on overall memories was moderated by two constraints. First, sleep effects were influenced by the number of words within each themed word list, relating to differences in processing of the associative network of related words. Second, sleep effects were greater in recall than in recognition tests. Thus, whether sleep consolidation increased or decreased DRM veridical or false memory effects depended on the specific features of the memory task.

Higher sleep spindle activity is associated with fewer false memories in adolescent girls

BACKGROUND

Sleep facilitates the extraction of semantic regularities amongst newly encoded memories, which may also lead to increased false memories. We investigated sleep stage proportions and sleep spindles in the recollection of adolescents' false memories, and their potential sex-specific differences.

METHODS

196 adolescents (mean age 16.9 y; SD = 0.1, 61% girls) underwent the Deese, Roediger & McDermott (DRM) false memory procedure and overnight polysomnography, with free recall the following morning. Sleep was scored manually into stages 1, 2, 3 and REM. Stage 2 sleep spindle frequency, density, and peak amplitude were used as measures of spindle activity for slow (10-13 Hz) and fast (13-16 Hz) ranges.

RESULTS

In girls, a lower number of critical lures was associated with higher spindle frequency (p ≤ 0.01), density (p ≤ 0.01), and amplitude (p = 0.03). Additionally, girls' longer sleep duration was associated with more intrusion words (p = 0.03), but not with critical lures. These associations survived adjustment for age, pubertal status, and intelligence. No significant results emerged in boys.

CONCLUSIONS

In adolescent girls, higher spindle activity was associated with fewer critical lures being falsely recalled in the DRM paradigm. Unlike studies using adult participants, we did not observe any association between slow-wave sleep and false memory recollection.

Increased phantom recollection after sleep

Sleep is known to benefit memory consolidation, but its effect on false memory is less clear. We applied the simplified conjoint recognition paradigm to investigate how sleep affects the cognitive processes behind correct or false recognition, according to fuzzy-trace theory, and measured the retrieval of verbatim traces, retrieval of gist traces, and phantom recollection. Participants studied 24 lists of semantically related words lacking the strongest common associate or theme word. Recognition was tested 12 h later, following either a night's sleep or daytime wakefulness. The recognition test featured studied words, nonstudied theme words (false recognition), and unrelated words. False recognition rate was higher after sleep than after daytime wakefulness. True recognition rate was the same. Analysis of the cognitive processes underlying recognition showed that phantom recollection was higher after sleep. Assuming that phantom recollection reflects the retrieval of strong gist traces, sleep may strengthen gist traces and promote gist extraction.

Sleep and mindfulness meditation as they relate to false memory

By a systematic analysis of the current literature, we compare two states of sleep and meditation in terms of their role in the formation or suppression of Deese-Roediger-McDermott (DRM) false memory. We aim to suggest that the occurrence of false memory under these two states is a result of reinforcing some abilities and changes in cognitive systems which can ultimately improve some aspects of cognitive functions. In our analogy, we propose that: (1) both sleep and meditation may improve source monitoring ability whose failure is one of the most important mechanisms in producing false memories, and (2) despite improvement in source monitoring ability, adaptive cognitive processes, as mechanisms which are common in sleep and meditation, can still produce false memories. In conclusion, we propose that in spite of their contribution to false memory through adaptive processes, the beneficial role of sleep and meditation in cognition may be more prominent than their harmful role.

Integrative Review of the Relationship Between Sleep Disturbances and Episodic Memory in Older Adults

Impaired episodic memory in older adults has been linked to many factors. One of these factors is sleep disturbances, which are reported by more than 50% of older adults. The relationship between episodic memory and sleep disturbances remains unclear, however, because of the multiple types of measures of sleep and episodic memory used in previous studies. The purpose of this integrative literature review was to integrate and compare findings on this relationship in adults aged 65 years. An electronic search was conducted in PubMed, Cumulative Index to Nursing and Allied Health Literature, PsychINFO, and Medline for material published from the inception of the databases to December 2016. The literature search produced 13 data-based, peer-reviewed, and primary research articles that met eligibility criteria. The synthesized results from these articles provide evidence that older adults with 6-8 hr of self-reported total sleep time had better episodic memory than older adults with ≤5 hr or ≥9 hr of total sleep time. Shorter length and lower percentage of slow-wave sleep were associated with reduced episodic memory in older adults, but the results were controversial. Selection of different measurements and inconsistent variables across studies increased the difficulty of synthesizing and comparing the results. The diversity of covariates controlled in the included articles raise questions regarding which covariates should be controlled in such studies of sleep and episodic memory in older adults. The numerous study limitations were thus major barriers to understanding the relationship between sleep disturbances and episodic memory.

Sleep and eyewitness memory: Fewer false identifications after sleep when the target is absent from the lineup

Inaccurate eyewitness identifications are the leading cause of known false convictions in the United States. Moreover, improving eyewitness memory is difficult and often unsuccessful. Sleep consistently strengthens and protects memory from interference, particularly when a recall test is used. However, the effect of sleep on recognition memory is more equivocal. Eyewitness identification tests are often recognition based, thus leaving open the question of how sleep affects recognition performance in an eyewitness context. In the current study, we investigated the effect of sleep on eyewitness memory. Participants watched a video of a mock-crime and attempted to identify the perpetrator from a simultaneous lineup after a 12-hour retention interval that either spanned a waking day or night of sleep. In Experiment 1, we used a target-present lineup and, in Experiment 2, we used a target-absent lineup in order to investigate correct and false identifications, respectively. Sleep reduced false identifications in the target-absent lineup (Experiment 2) but had no effect on correct identifications in the target-present lineup (Experiment 1). These results are discussed with respect to memory strength and decision making strategies.

Sleep does not cause false memories on a story-based test of suggestibility

Sleep contributes to the consolidation of memories. This process may involve extracting the gist of learned material at the expense of details. It has thus been proposed that sleep might lead to false memory formation. Previous research examined the effect of sleep on false memory using the Deese-Roediger-McDermott (DRM) paradigm. Mixed results were found, including increases and decreases in false memory after sleep relative to wake. It has been questioned whether DRM false memories occur by the same processes as real-world false memories. Here, the effect of sleep on false memory was investigated using the Gudjonsson Suggestibility Scale. Veridical memory deteriorated after a 12-h period of wake, but not after a 12-h period including a night's sleep. No difference in false memory was found between conditions. Although the literature supports sleep-dependent memory consolidation, the results here call into question extending this to a gist-based false memory effect.

Sleep and Human Aging

Older adults do not sleep as well as younger adults. Why? What alterations in sleep quantity and quality occur as we age, and are there functional consequences? What are the underlying neural mechanisms that explain age-related sleep disruption? This review tackles these questions. First, we describe canonical changes in human sleep quantity and quality in cognitively normal older adults. Second, we explore the underlying neurobiological mechanisms that may account for these human sleep alterations. Third, we consider the functional consequences of age-related sleep disruption, focusing on memory impairment as an exemplar. We conclude with a discussion of a still-debated question: do older adults simply need less sleep, or rather, are they unable to generate the sleep that they still need?

Sleep Supports the Slow Abstraction of Gist from Visual Perceptual Memories

Sleep benefits the consolidation of individual episodic memories. In the long run, however, it may be more efficient to retain the abstract gist of single, related memories, which can be generalized to similar instances in the future. While episodic memory is enhanced after one night of sleep, effective gist abstraction is thought to require multiple nights. We tested this hypothesis using a visual Deese-Roediger-McDermott paradigm, examining gist abstraction and episodic-like memory consolidation after 20 min, after 10 hours, as well as after one year of retention. While after 10 hours, sleep enhanced episodic-like memory for single items, it did not affect gist abstraction. One year later, however, we found significant gist knowledge only if subjects had slept immediately after encoding, while there was no residual memory for individual items. These findings indicate that sleep after learning strengthens episodic-like memories in the short term and facilitates long-term gist abstraction.

The Deese-Roediger-McDermott (DRM) Task: A Simple Cognitive Paradigm to Investigate False Memories in the Laboratory

The Deese, Roediger and McDermott (DRM) task is a false memory paradigm in which subjects are presented with lists of semantically related words (e.g., nurse, hospital, etc.) at encoding. After a delay, subjects are asked to recall or recognize these words. In the recognition memory version of the task, subjects are asked whether they remember previously presented words, as well as related (but never presented) critical lure words ('doctor'). Typically, the critical word is recognized with high probability and confidence. This false memory effect has been robustly demonstrated across short (e.g., immediate, 20 min) and long (e.g., 1, 7, 60 d) delays between encoding and memory testing. A strength of using this task to study false memory is its simplicity and short duration. If encoding and retrieval components of the task occur in the same session, the entire task can take as little as 2 - 30 min. However, although the DRM task is widely considered a 'false memory' paradigm, some researchers consider DRM illusions to be based on the activation of semantic memory networks in the brain, and argue that such semantic gist-based false memory errors may actually be useful in some scenarios (e.g., remembering the forest for the trees; remembering that a word list was about "doctors", even though the actual word "doctor" was never presented for study). Remembering the gist of experience (instead of or along with individual details) is arguably an adaptive process and this task has provided a great deal of knowledge about the constructive, adaptive nature of memory. Therefore, researchers should use caution when discussing the overall reach and implications of their experiments when using this task to study 'false memory', as DRM memory errors may not adequately reflect false memories in the real world, such as false memory in eyewitness testimony, or false memories of sexual abuse.

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

This study examined the differential effects of aging on consolidation processes that strengthen newly acquired memory traces in veridical form (memory stabilization) versus consolidation processes that are responsible for integrating these memory traces into an existing body of knowledge (item integration). Older adults learned 13 nonwords and were tested on their memory for the nonwords, and on whether these nonwords impacted upon processing of similar-sounding English words immediately and 24 hours later. Participants accurately recognized the nonwords immediately, but showed significant decreases in delayed recognition and recall. In comparison, the nonwords impacted upon processing of similar-sounding words only in the delayed test. Together, these findings suggest that memory consolidation processes may be more evident in item integration than memory stabilization processes for new declarative memories in older adults.

Sleep deprivation increases formation of false memory

Retrieving false information can have serious consequences. Sleep is important for memory, but voluntary sleep curtailment is becoming more rampant. Here, the misinformation paradigm was used to investigate false memory formation after 1 night of total sleep deprivation in healthy young adults (N = 58, mean age ± SD = 22.10 ± 1.60 years; 29 males), and 7 nights of partial sleep deprivation (5 h sleep opportunity) in these young adults and healthy adolescents (N = 54, mean age ± SD = 16.67 ± 1.03 years; 25 males). In both age groups, sleep-deprived individuals were more likely than well-rested persons to incorporate misleading post-event information into their responses during memory retrieval (P < 0.050). These findings reiterate the importance of adequate sleep in optimal cognitive functioning, reveal the vulnerability of adolescents' memory during sleep curtailment, and suggest the need to assess eyewitnesses' sleep history after encountering misleading information.

Sleep, cognition, and normal aging: integrating a half century of multidisciplinary research

Sleep is implicated in cognitive functioning in young adults. With increasing age, there are substantial changes to sleep quantity and quality, including changes to slow-wave sleep, spindle density, and sleep continuity/fragmentation. A provocative question for the field of cognitive aging is whether such changes in sleep physiology affect cognition (e.g., memory consolidation). We review nearly a half century of research across seven diverse correlational and experimental domains that historically have had little crosstalk. Broadly speaking, sleep and cognitive functions are often related in advancing age, though the prevalence of null effects in healthy older adults (including correlations in the unexpected, negative direction) indicates that age may be an effect modifier of these associations. We interpret the literature as suggesting that maintaining good sleep quality, at least in young adulthood and middle age, promotes better cognitive functioning and serves to protect against age-related cognitive declines.