Subsequent Memory Performance Research Articles

Offset-related brain activity in the left ventrolateral prefrontal cortex promotes long-term memory formation of verbal events

BackgroundRecent evidence suggests that brain activity following the offset of a stimulus during encoding contributes to long-term memory formation, however the exact mechanisms underlying offset-related encoding are still unclear. ObjectivesHere, in three repetitive transcranial magnetic stimulation studies (rTMS) we investigated offset-related activity in the left ventrolateral prefrontal cortex (VLPFC). rTMS was administered at different points in time around stimulus offset while participants encoded visually-presented words or pairs of words. The analyses focused on the effects of the stimulation on subsequent memory performance. ResultsrTMS administered at the offset of the stimuli, but not during online encoding, disrupted subsequent memory performance. In Experiment 1 we found that rTMS specifically disrupted encoding mechanisms initiated by the offset of the stimuli rather than general, post-stimulus processes. Experiment 2 showed that this effect was not dependent upon rTMS-induced somatosensory effects. In a third rTMS experiment we further demonstrated a robust decline in associative memory performance when the stimulation was delivered at the offset of the word pairs, suggesting that offset-related encoding may contribute to the binding of information into an episodic memory trace. ConclusionsThe offset of the stimulus may represent an event boundary that promotes the reinstatement of the previously experienced event and episodic binding.

Tracking Age Differences in Neural Distinctiveness across Representational Levels.

The distinctiveness of neural information representation is crucial for successful memory performance but declines with advancing age. Computational models implicate age-related neural dedifferentiation on the level of item representations, but previous studies mostly focused on age differences of categorical information representation in higher-order visual regions. In an age-comparative fMRI study, we combined univariate analyses and whole-brain searchlight pattern similarity analyses to elucidate age differences in neural distinctiveness at both category and item levels and their relation to memory. Thirty-five younger (18-27 years old) and 32 older (67-75 years old) women and men incidentally encoded images of faces and houses, followed by an old/new recognition memory task. During encoding, age-related neural dedifferentiation was shown as reduced category-selective processing in ventral visual cortex and impoverished item specificity in occipital regions. Importantly, successful subsequent memory performance built on high item stability, that is, high representational similarity between initial and repeated presentation of an item, which was greater in younger than older adults. Overall, we found that differences in representational distinctiveness coexist across representational levels and contribute to interindividual and intraindividual variability in memory success, with item specificity being the strongest contributor. Our results close an important gap in the literature, showing that older adults' neural representation of item-specific information in addition to categorical information is reduced compared with younger adults.SIGNIFICANCE STATEMENT A long-standing hypothesis links age-related cognitive decline to a loss of neural specificity. While previous evidence supports the notion of age-related neural dedifferentiation of category-level information in ventral visual cortex, whether or not age differences exist at the item level was a matter of debate. Here, we observed age group differences at both levels as well as associations between both categorical distinctiveness and item specificity to memory performance, with item specificity being the strongest contributor. Importantly, age differences in occipital item specificity were largely due to reduced item stability across repetitions in older adults. Our results suggest that age differences in neural representations can be observed across the entire cortical hierarchy and are not limited to category-level information.

Horizontal but not vertical saccades enhance memory retrieval: A meta-analysis and systematic review.

Saccade-induced retrieval enhancement (SIRE) refers to the phenomenon that actively engaging in horizontal eye movements before recall enhances subsequent memory performance. This effect is thought to be the result of interhemispheric interactions stimulated by saccades. An alternative explanation is that saccades promote memory retrieval by improving top-down attention control. Thus, the mechanisms of SIRE are unclear, and the present meta-analysis quantitatively analysed the effect of saccades on memory performance and examined the mechanisms of SIRE. We searched "Web of Science," "PubMed," and "Springer" for peer-reviewed papers using the keywords "eye movements + memory" and "saccades + memory." Twenty-two papers were included in the final analysis. There was a significant facilitation of horizontal saccades on overall memory performance, with a pooled effect size (Cohen's d) of 0.45 (p < .001). However, the overall effect of vertical saccades was not significant (d = 0.1, p = .14). Moderation analysis showed that the handedness of participants was a significant moderator of SIRE, with strongly right-handed individuals benefitting more from horizontal saccades than non-strongly right-handed individuals (p < .01). Horizontal saccades improved memory performance, particularly for strongly right-handed individuals. These results support the interhemispheric interaction hypothesis.

The phase of Theta oscillations modulates successful memory formation at encoding

Several studies have shown that attention and perception can depend upon the phase of ongoing neural oscillations at stimulus onset. Here, we extend this idea to the memory domain. We tested the hypothesis that ongoing fluctuations in neural activity impact memory encoding in two experiments using a picture paired-associates task in order to gauge episodic memory performance. Experiment 1 was behavioural only and capitalized on the principle of phase resetting. We tested if subsequent memory performance fluctuates rhythmically, time-locked to a resetting cue presented before the to-be-remembered pairs at different time intervals. We found an indication that behavioural performance was periodically and selectively modulated at Theta frequency (~4 Hz). In Experiment 2, we focused on pre-stimulus ongoing activity using scalp EEG while participants performed a paired-associates task. The pre-registered analysis, using large electrode clusters and generic Theta and Alpha spectral ranges, returned null results of the pre-stimulus phase-behaviour correlation. However, as expected from prior literature, we found that variations in stimulus-related Theta-power predicted subsequent memory performance. Therefore, we used this post-stimulus effect in Theta power to guide a post-hoc pre-stimulus phase analysis in terms of scalp and frequency of interest. This analysis returned a correlation between the pre-stimulus Theta phase and subsequent memory. Altogether, these results suggest that pre-stimulus Theta activity at encoding may impact later memory performance.

Working memory consolidation improves long-term memory recognition.

Recent research has found that maintaining an item in working memory improves subsequent long-term memory performance. The present study explored the role of working memory consolidation in long-term recognition. Participants completed a stimuli-identification task followed by a surprise delayed recognition task. Participants first identified which one of four stimuli matched a target stimulus. The target item was presented either just before or simultaneously with the response set. This manipulation requires the participant to consolidate the target into working memory in the before presentation condition but not in the simultaneous presentation condition. Delayed recognition for the target items was then tested. Despite a slight performance advantage for the simultaneous presentation condition in the stimuli-identification task, long-term recognition performance was considerably better for target items presented in the before presentation condition. These results suggest that consolidation into working memory and not simply attending to an item improves long-term memory performance. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Alpha modulation in younger and older adults during distracted encoding.

To successfully encode information into long-term memory, we need top-down control to focus our attention on target stimuli. This attentional focus is achieved by the modulation of sensory neuronal excitability through alpha power. Failure to modulate alpha power and to inhibit distracting information has been reported in older adults during attention and working memory tasks. Given that alpha power during encoding can predict subsequent memory performance, aberrant oscillatory modulations might play a role in age-related memory deficits. However, it is unknown whether there are age-related differences in memory performance or alpha modulation when encoding targets with distraction. Here we show that both older and younger adults are able to encode targets paired with distractors and that the level of alpha power modulation during encoding predicted recognition success. Even though older adults showed signs of higher distractibility, this did not harm their episodic memory for target information. Also, we demonstrate that older adults only modulated alpha power during high distraction, both by enhancing target processing and inhibiting distractor processing. These results indicate that both younger and older adults are able to employ the same inhibitory control mechanisms successfully, but that older adults fail to call upon these when distraction is minimal. The findings of this study give us more insight into the mechanisms involved in memory encoding across the lifespan.

Age moderation of the association between negative subsequent memory effects and episodic memory performance.

Negative subsequent memory effects in functional MRI studies of memory formation have been linked to individual differences in memory performance, yet the effect of age on this association is currently unclear. To provide insight into the brain systems related to memory across the lifespan, we examined functional neuroimaging data acquired during episodic memory formation and behavioral performance from a memory recognition task in a sample of 109 participants, including three developmental age groups (8-12, 13-17, 18-25 year-olds) and one additional group of older adults (55-85 year-olds). Young adults showed the highest memory performance and strongest negative subsequent memory effects, while older adults showed reduced negative subsequent memory effects relative to young adults. Across the sample, negative subsequent memory effects were associated with better memory performance, and there was a significant interaction between negative subsequent memory effects and memory performance by age group. Posthoc analyses revealed that this moderation effect was driven by a stronger association between negative subsequent memory effects and memory performance in young adults than children, and that neither children nor older adults showed a significant association. These findings suggest that negative subsequent memory effects may differentially support memory performance across a lifespan trajectory characterized by developmental maturation and support further investigation of this effect in aging.

The influence of light exposure and chronotype on working memory in humans

Here we examine how exposure to blue (peaking at λ=470 nm), green (peaking at λ=505 nm) and red (peaking at λ=630 nm) light affects subsequent working memory performance measured with visual N-back tasks and associated functional brain responses in participants with extreme morning and extreme evening chronotype. We used within-subjects experimental manipulation on carefully selected samples and state of the art equipment for light exposure. The results show no differences between extreme morning-type and evening-type individuals in N-back task performance. We also did not replicate the alerting effect of exposure to blue wavelength light, supposedly enhancing performance on cognitive tasks. However, we found higher brain activity in the morning hours for extreme morning in comparison to extreme evening chronotype in several frontal areas of the precentral gyrus, middle and superior frontal gyri and in the occipital gyrus. This may indicate increased strategic or attentional recruitment of prefrontal areas, implicated in compensating working memory load in the morning type.

Memory of my victory and your defeat: Contributions of reward- and memory-related regions to the encoding of winning events in competitions with others

Social interactions enhance human memories, but little is known about how the neural mechanisms underlying episodic memories are modulated by rewarding outcomes in social interactions. To investigate this, fMRI data were recorded while healthy young adults encoded unfamiliar faces in either a competition or a control task. In the competition task, participants encoded opponents' faces in the rock-paper-scissors game, where trial-by-trial outcomes of Win, Draw, and Lose for participants were shown by facial expressions of opponents (Angry, Neutral, and Happy). In the control task, participants encoded faces by assessing facial expressions. After encoding, participants recognized faces previously learned. Behavioral data showed that emotional valence for opponents' Angry faces as the Win outcome was rated positively in the competition task, whereas the rating for Angry faces was rated negatively in the control task, and that Angry faces were remembered more accurately than Neutral or Happy faces in both tasks. fMRI data showed that activation in the medial orbitofrontal cortex (mOFC) paralleled the pattern of valence ratings, with greater activation for the Win than Draw or Lose conditions of the competition task, and the Angry condition of the control task. Moreover, functional connectivity between the mOFC and hippocampus was increased in Win compared to Angry, and the mOFC-hippocampus functional connectivity predicted individual differences in subsequent memory performance only in Win of the competition task, but not in any other conditions of the two tasks. These results demonstrate that the memory enhancement by context-dependent social rewards involves interactions between reward- and memory-related regions.

Latent patterns of task‐related functional connectivity relate to hyperactivation and associative memory impairment in SCD+ and MCI

AbstractBackgroundHyperactivation is commonly observed in prodromal Alzheimer’s disease (AD). It is however unknown if it relates to functional network dysfunction, and how hyperactivation‐networks relate to cognitive impairment. We used seed‐based connectivity to assess differences in correlations between activation of hyperactive regions, whole‐brain task‐related activation, and memory performance in persons with subjective cognitive decline plus (SCD+) and mild cognitive impairment (MCI).MethodData from 108 participants from the CIMA‐Q cohort were used in this study: 28 participants with SCD+ which presented with memory complaint and worry in addition to small hippocampal volume and/or were APOE4 carriers, 26 participants with MCI and 54 were healthy controls (HC). Task‐related activation was measured while participants memorized 78 pictures and their location in a four‐position grid. Multivariate seed‐partial least squares (seed‐PLS) analysis was used to identify latent variables (LVs) that assess between‐group differences and similarities in the three‐way association between 1) activation in hyperactive regions of interest (ROIs: left hippocampus, right inferior temporal gyrus (riTG), left superior parietal lobule (lsPL)), 2) whole‐brain activation associated with associative memory encoding, and 3) subsequent associative memory performance. Significance of the seed‐PLS effects were assessed with permutation testing and boostraps.ResultThree LVs were significant (p &lt; 0.05). LV1 (32.11 % of covariance explained) accounted for group similarities in the correlation between activity in all ROIs and activity in the fronto‐parietal and default mode networks. Interestingly, left hippocampus activity did not correlate in SCD+. LV2 (19.17 % of covariance explained) identified a network that was correlated with left hippocampal activity in all three groups; however, left hippocampal activity correlated with better memory in HC but with poorer memory in SCD+. LV3 (10.91 % of covariance explained) identified a network that was positively correlated to lsPL activity in SCD+, and correlated with seed activity in all ROIs and poorer memory performance in MCI.ConclusionHyperactivation is associated with latent patterns of connectivity in prodromal AD, but different hyperactivation‐network associations relate to memory in SCD+ and MCI. Hyperactivation could serve as an early marker of network dysfunction in AD, and reflect the incoming cognitive symptomatology associated with the disease.

Single-Trial EEG Connectivity of Default Mode Network Before and During Encoding Predicts Subsequent Memory Outcome.

The successful memory process produces specific activity in the brain network. As the brain activity of the prestimulus and encoding phases has a crucial effect on subsequent memory outcomes (e.g., remembered or forgotten), previous studies have tried to predict the memory performance in this period. Conventional studies have used the spectral power or event-related potential of specific regions as the classification feature. However, as multiple brain regions work collaboratively to process memory, it could be a better option to use functional connectivity within the memory-related brain network to predict subsequent memory performance. In this study, we acquired the EEG signals while performing an associative memory task that remembers scene–word pairs. For the connectivity analysis, we estimated the cross–mutual information within the default mode network with the time–frequency spectra at the prestimulus and encoding phases. Then, we predicted the success or failure of subsequent memory outcome with the connectivity features. We found that the classifier with support vector machine achieved the highest classification accuracy of 80.83% ± 12.65% (mean ± standard deviation) using the beta (13–30 Hz) connectivity at encoding phase among the multiple frequency bands and task phases. Using the prestimulus beta connectivity, the classification accuracy of 72.45% ± 12.52% is also achieved. Among the features, the connectivity related to the dorsomedial prefrontal cortex was found to contribute to successful memory encoding. The connectivity related to the posterior cingulate cortex was found to contribute to the failure of memory encoding. The present study showed for the first time the successful prediction with high accuracy of subsequent memory outcome using single-trial functional connectivity.

Dopamine Related Genes Differentially Affect Declarative Long-Term Memory in Healthy Humans.

In humans, monetary reward can promote behavioral performance including response times, accuracy, and subsequent recognition memory. Recent studies have shown that the dopaminergic system plays an essential role here, but the link to interindividual differences remains unclear. To further investigate this issue, we focused on previously described polymorphisms of genes affecting dopaminergic neurotransmission: DAT1 40 base pair (bp), DAT1 30 bp, DRD4 48 bp, and cannabinoid receptor type 1 (CNR1). Specifically, 669 healthy humans participated in a delayed recognition memory paradigm on two consecutive days. On the first day, male vs. female faces served as cues predicting an immediate monetary reward upon correct button presses. Subsequently, participants performed a remember/know recognition memory task on the same day and 1 day later. As predicted, reward increased accuracy and accelerated response times, which were modulated by DAT 30 bp. However, reward did not promote subsequent recognition memory performance and there was no interaction with any genotype tested here. Importantly, there were differential effects of genotype on declarative long-term memory independent of reward: (a) DAT1 40 bp was linked to the quality of memory with a more pronounced difference between recollection and familiarity in the heterozygous and homozygous 10-R as compared to homozygous 9-R; (b) DAT1 30 bp was linked to memory decay, which was most pronounced in homozygous 4-R; (c) DRD4 48 bp was linked to overall recognition memory with higher performance in the short allele group; and (d) CNR1 was linked to overall memory with reduced performance in the homozygous short group. These findings give new insights into how polymorphisms, which are related to dopaminergic neuromodulation, differentially affect long-term recognition memory performance.

The effect of shared distinctiveness on source memory: An event-related potential study

An illusory correlation (IC) is the erroneous perception that two actually uncorrelated categories are correlated. The Shared Distinctiveness Approach (SDA) explains ICs with heightened accessibility of distinctive category combinations in episodic memory. However, empirical evidence for this approach is heterogeneous. In the present event-related potential (ERP) study, we exploited the fact that more distinctive items elicit larger P300 responses than less distinctive items, which potentially predict subsequent memory performance differences for such items. Distinctiveness at encoding was created by presenting words that differed from frequently presented, positive words in valence, font color, or both. We hypothesized that shared distinctiveness (deviation in both color and valence) would lead to an enhanced P300 subsequent memory effect (SME), better source memory performance, and an overestimation of the frequency of shared distinctive items. Behavioral results indicated the presence of shared distinctiveness effects on source memory and frequency estimation. Unexpectedly, memory also was enhanced for positive items in the frequent color. This pattern also was reflected in the P300 for highly positive and negative items. However, shared distinctiveness did not modulate the P300 SME, indicating that the processing of distinctive features might only indirectly contribute to better encoding. This study shows that shared distinctiveness indeed is associated with better source memory and ICs. Because effects were observed for the most frequent and the least frequent category combination, our results imply that the processing of distinctiveness might involve attention allocation to diametrical category combinations, thereby accentuating the differences between the categories.

Assessing Rhythmic Visual Entrainment and Reinstatement of Brain Oscillations to Modulate Memory Performance.

The human brain’s ability to store information and remember past events is thought to be orchestrated by the synchronization of neuronal oscillations in various frequency bands. A vast amount of research has found that neural oscillations in the theta (∼4–7 Hz) and alpha (∼8–12 Hz) bands play an important role in memory formation. More specifically, it has been suggested that memory performance benefits if the same oscillatory pattern is present during encoding and retrieval. However, the causal relevance of these oscillations is not well understood. Rhythmic sensory stimulation is thought to entrain ongoing brain oscillations and modulate associated functions (e.g., memory formation). In the present study, we used rhythmic visual stimulation at 6 and 10 Hz to experimentally modulate the memory encoding process in a recognition memory task. In addition, we reinstated oscillatory activity from the encoding episode during retrieval, which has been hypothesized to result in memory performance improvements compared to non-reinstated conditions and incongruent reinstatement. Contrary to our hypothesis, we find no effect of neural entrainment during encoding on subsequent memory performance. Likewise, memory retrieval does not benefit from neural reinstatement. The results are discussed with respect to methodological challenges of rhythmic sensory stimulation as a means to alter cognitive processes and induce context-dependent memory effects.

Hippocampal efferents to retrosplenial cortex and lateral septum are required for memory acquisition

Learning and memory involves a large neural network of many brain regions, including the notable hippocampus along with the retrosplenial cortex (RSC) and lateral septum (LS). Previous studies have established that the dorsal hippocampus (dHPC) plays a critical role during the acquisition and retrieval/expression of episodic memories. However, the role of downstream circuitry from the dHPC, including the dHPC-to-RSC and dHPC-to-LS pathways, has come under scrutiny only recently. Here, we used an optogenetic approach with contextual fear conditioning in mice to determine whether the above two pathways are involved in acquisition and expression of contextual fear memory. We found that a selective inhibition of the dHPC neuronal terminals in either the RSC or LS during acquisition impaired subsequent memory performance, suggesting that both the dHPC-to-RSC and dHPC-to-LS pathways play a critical role in memory acquisition. We also selectively inhibited the two dHPC efferent pathways during memory retrieval and found a differential effect on memory performance. These results indicate the intricacies of memory processing and that hippocampal efferents to cortical and subcortical regions may be differentially involved in aspects of physiological and cognitive memory processes.

Blessedly forgetful and blissfully unaware: a positivity bias in memory for (re)constructions of imagined past and future events

ABSTRACT People frequently consider the alternatives of the events that can happen in the future and of the events that already happened in the past in everyday life. The current study investigates the effects of engaging in imagination of hypothetical future (Experiment 1) and past (Experiment 2) events on memory and metamemory. We demonstrate, across two experiments, that imagination of positive future and positive past events yielded greater memory performance than negative events, as well as receiving higher vividness and plausibility ratings. In addition, simulation of a negative event occurring positively in the future or having occurred positively in the past produced higher memory performance, compared to simulation of a positive event occurring / having occurred negatively. However, participants’ predictions for their subsequent memory performance did not reflect their increased tendency to remember positive or could-be / could-have-been positive events neither for future nor past reconstructions. These findings are interpreted in the framework of positivity bias which suggests that people have a tendency towards positivity when simulating future events; and we extend this positivity bias to reconstructions of the hypothetical past events as well.

Disrupted Relationship between Hippocampal Activation and Subsequent Memory Performance in Borderline Personality Disorder

BackgroundBorderline personality disorder (BPD) is associated with subjective reports of forgetfulness and deficits on tests of memory performance. However, it is not yet known whether individuals with BPD show different patterns of activation in the hippocampus during episodic memory encoding, especially for materials that are not emotionally-valenced. MethodsParticipants with BPD (n = 20) and non-psychiatric controls (n = 21) completed a memory encoding task in which they viewed scenes without emotional content during functional magnetic resonance imaging scans. Subsequently, they completed a recognition memory test outside of the scanner and neural activation during the presentation of successfully remembered scenes was contrasted with scenes that were subsequently forgotten. ResultsControls exhibited significant left hippocampal activation during successful memory encoding, displaying greater activity during the presentation of subsequently remembered versus forgotten scenes, and the strength of this activation was related to their recognition memory performance. Although hippocampal activation was observed for the BPD group during successful memory encoding, it did not reach significance when implementing a non-parametric statistical approach. Additionally, individual hippocampal recruitment was not significantly correlated with recognition memory performance in the BPD group. The strength of this correlation, but not the overall magnitude of hippocampal activation, was significantly different between the groups. LimitationsParticipants with BPD had comorbid psychiatric diagnoses and varied treatment histories. Whether patients and controls differentially perceived emotional content in the neutral scene memoranda was not tested. ConclusionsMemory problems in BPD may be partially explained by a disrupted relationship between hippocampal activation and successful memory encoding.

The association between cognitive reserve and performance-related brain activity during episodic encoding and retrieval across the adult lifespan

Remembering associations between encoded items and their contextual setting is a feature of episodic memory. Although this ability generally deteriorates with age, there is substantial variability in how older individuals perform on episodic memory tasks. A current topic of debate in the cognitive neuroscience of aging literature revolves around whether this variability may stem from genetic and/or environmental factors related to reserve, allowing some individuals to compensate for age-related decline through differential recruitment of brain regions. In this fMRI study spanning a large adult lifespan sample (N = 154), we tested whether higher cognitive reserve was associated with better task-fMRI context memory performance, and functional compensatory activity patterns in the aging brain. We used multivariate Behaviour Partial Least Squares (B-PLS) analysis to examine how age, retrieval accuracy, and a proxy measure of cognitive reserve [i.e., a composite score consisting of years of education (EDU) and crystallized IQ], impacted brain activity during the encoding and retrieval of spatial and temporal contextual details. The results indicated that age-related increases in encoding activity within anterior and lateral frontal, inferior parietal, occipito-temporal and medial temporal cortices, was correlated with better subsequent memory performance; and may be indicative of age-related functional compensation at encoding. Interestingly this compensatory pattern was not correlated with our proxy measure of cognitive reserve but was associated with total brain volume (a measure of brain reserve). However, cognitive reserve was associated with age-invariant and task-general activity in superior temporal, occipital, and left inferior frontal regions. We conclude that the relationship between cognitive reserve, brain reserve and age-related functional compensation is complex, and that EDU and IQ may not fully account for individual differences in cognitive reserve when studying well educated, healthy aging cohorts.

Neural Differentiation is Moderated by Age in Scene-Selective, But Not Face-Selective, Cortical Regions.

The aging brain is characterized by neural dedifferentiation, an apparent decrease in the functional selectivity of category-selective cortical regions. Age-related reductions in neural differentiation have been proposed to play a causal role in cognitive aging. Recent findings suggest, however, that age-related dedifferentiation is not equally evident for all stimulus categories and, additionally, that the relationship between neural differentiation and cognitive performance is not moderated by age. In light of these findings, in the present experiment, younger and older human adults (males and females) underwent fMRI as they studied words paired with images of scenes or faces before a subsequent memory task. Neural selectivity was measured in two scene-selective (parahippocampal place area (PPA) and retrosplenial cortex (RSC)] and two face-selective [fusiform face area (FFA) and occipital face area (OFA)] regions using both a univariate differentiation index and multivoxel pattern similarity analysis. Both methods provided highly convergent results, which revealed evidence of age-related reductions in neural dedifferentiation in scene-selective but not face-selective cortical regions. Additionally, neural differentiation in the PPA demonstrated a positive, age-invariant relationship with subsequent source memory performance (recall of the image category paired with each recognized test word). These findings extend prior findings suggesting that age-related neural dedifferentiation is not a ubiquitous phenomenon, and that the specificity of neural responses to scenes is predictive of subsequent memory performance independently of age.

Specifying the mechanisms behind benefits of saving-enhanced memory.

By saving information on external memory stores, we can offload temporarily irrelevant memories, we believe to be important in the future. The external saving of encoded items enhances subsequent memory performance for new information (Storm and Stone in Psychol Sci 26(2):182-188, 2015). Across three experiments, we replicated and specified this saving-enhanced memory effect. In Experiment 1, we replicated the benefits of saving and showed that they are robust against changes in instructions. In Experiment 2, we extended the saving-enhanced memory effect to motor material and more important, found evidence for better encoding after saving. In Experiment 3, a cost effect for saved verbal material was present, indicating that externally saving information can reduce the accessibility for this information afterwards. These findings suggest that at least two factors contribute to benefits of saving, better encoding and reduced interference at recall. Hereby, similarities of saving-enhanced memory to effects of the list-method directed forgetting phenomenon and useful implications for our daily information management are provided.