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The literature on the relationship between social interaction and executive functions (EF) in older age is mixed, perhaps stemming from differences in EF measures and the conceptualization/measurement of social interaction. We investigated the relationship between social interaction and EF in 102 cognitively unimpaired older adults (ages 65-90). Participants received an EF battery to measure working memory, inhibition, shifting, and global EF. We measured loneliness subjectively through survey and social isolation objectively through naturalistic observation. Loneliness was not significantly related to any EF measure ( p -values = .13-.65), nor was social isolation ( p -values = .11-.69). Bayes factors indicated moderate to extremely strong evidence ( BF 01  = 8.70 to BF 01  = 119.49) in support of no relationship..   Overall, these findings suggest that, among cognitively healthy older adults, there may not be a robust cross-sectional relationship between EF and subjective loneliness or objective social isolation.

Episodic memory and executive function are two cognitive domains that have been studied extensively in older adults and have been shown to decline in normally-aging older individuals. However, one of the problems with characterizing cognitive changes in longitudinal studies has been separating effects attributable to normal aging from effects created by repeated testing or practice. In the present study, 166 people aged 65 and older were enrolled over several years and tested at least 3 times at variable intervals ( M = 3.2 yrs). The cognitive measures were composite scores. Each composite was made up of five neuropsychological tests, previously identified through factor analysis. For one pair of composite scores, variance attributable to age was removed from each subtest through regression analyses before z -scores were computed, creating two age-corrected composites. A second pair of composites were not age-corrected. Using linear mixed-effects models, we first explored retest effects for each cognitive domain, independent of age, using the age-corrected composites. We then modeled aging effects using the age-uncorrected composites after subtracting out retest effects. Results indicated significant retest effects for memory but not for executive function, such that memory performance improved across the three testing sessions. When these practice effects were removed from the age-uncorrected data, effects of aging were evident for both executive and memory function with significant declines over time. We also explored several individual difference variables including sex, IQ, and age at the initial testing session and across time. Although sex and IQ affected performance on both cognitive factors at the initial test, neither was related to practice effects, although young-older adults tended to benefit from practice to a greater extent than old-older adults. In addition, people with higher IQs showed slower age-related declines in memory, but no advantages in executive function. These findings suggest that (a) aging affects both memory and executive function similarly, (b) higher IQ, possibly reflecting cognitive reserve, may slow age-related declines in memory, and (c) practice through repeated testing enhances performance in memory particularly in younger-older adults, and may therefore mask aging effects if not taken into account., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Glisky, Woolverton, McVeigh and Grilli.)

Miyake and colleagues (2000) identified three independent but correlated components of executive function in young adults - set shifting, inhibition, and updating. The present study compared the factor structure in young adults to two groups of older adults (ages 60-73 and 74-98). A three-factor model of shifting, inhibition and updating was confirmed in young adults, but the factors were weakly or uncorrelated. In both older groups, a two-factor solution was indicated, updating/inhibition and shifting, which were moderately correlated in young-older adults, and strongly correlated in the old-older group. A nested factors model in the oldest group revealed a common factor, which loaded on all but one of the tests, and a shifting-specific factor. We concluded that in young adulthood, shifting, updating and inhibition may operate relatively independently. As people age and processing becomes less efficient, they may rely increasingly on general executive control processes, reallocating their limited resources to optimize performance.

Objectives: Language markers derived from structured clinical interviews and assessments have been found to predict age-related normal and pathological cognitive functioning. An important question, then, is the degree to which the language that people use in their natural daily interactions, rather than their language elicited within and specifically for clinical assessment, carries information about key cognitive functions associated with age-related decline. In an observational study, we investigated how variability in executive functioning (EF) manifests in patterns of daily word use., Method: Cognitively normal older adults (n = 102; mean age 76 years) wore the electronically activated recorder, an ambulatory monitoring device that intermittently recorded short snippets of ambient sounds, for 4 days, yielding an acoustic log of their daily conversations as they naturally unfolded. Verbatim transcripts of their captured utterances were text-analyzed using linguistic inquiring and word count. EF was assessed with a validated test battery measuring WM, shifting, and inhibitory control., Results: Controlling for age, education, and gender, higher overall EF, and particularly working memory, was associated with analytic (e.g., more articles and prepositions), complex (e.g., more longer words), and specific (e.g., more numbers) language in addition to other language markers (e.g., a relatively less positive emotional tone, more sexual and swear words)., Discussion: This study provides first evidence that the words older adults use in daily life provide a window into their EF., (© The Author(s) 2020. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The retrieval of autobiographical memories is an integral part of everyday social interactions. Prior laboratory research has revealed that older age is associated with a reduction in the retrieval of autobiographical episodic memories, and the ability to elaborate these memories with episodic details. However, how age-related reductions in episodic specificity unfold in everyday social contexts remains largely unknown. Also, constraints of the laboratory-based approach have limited our understanding of how autobiographical semantic memory is linked to older age. To address these gaps in knowledge, we used a smartphone application known as the Electronically Activated Recorder, or "EAR," to unobtrusively capture real-world conversations over 4 days. In a sample of 102 cognitively normal older adults, we extracted instances where memories and future thoughts were shared by the participants, and we scored the shared episodic memories and future thoughts for their make-up of episodic and semantic detail. We found that older age was associated with a reduction in real-world sharing of autobiographical episodic and semantic memories. We also found that older age was linked to less episodically and semantically detailed descriptions of autobiographical episodic memories. Frequency and level of detail of shared future thoughts yielded weaker relationships with age, which may be related to the low frequency of future thoughts in general. Similar to laboratory research, there was no correlation between autobiographical episodic detail sharing and a standard episodic memory test. However, in contrast to laboratory studies, episodic detail production while sharing autobiographical episodic memories was weakly related to episodic detail production while describing future events, unrelated to working memory, and not different between men and women. Overall, our findings provide novel evidence of how older age relates to episodic specificity when autobiographical memories are assessed unobtrusively and objectively "in the wild.", (Copyright © 2020 Wank, Mehl, Andrews-Hanna, Polsinelli, Moseley, Glisky and Grilli.)

We investigated whether the strategy of self-reference can benefit memory for multi-element events, a kind of relational memory that is relatively less studied but highly relevant to daily life. Young and older adults imagined different person-object-location events with reference to themselves and two famous others (i.e., George Clooney and Oprah Winfrey), rated the likelihood that each event would happen, and then completed incidental memory tests on different pairs of elements within the event. We found that self-reference enhanced memory for object-location and person-object pairs in both age groups. Such self-reference effects were observed consistently only for events rated as likely to happen. There was also an overall memory advantage for the higher-likelihood events, which did not differ between young and older adults. Further, the self-reference effects were not correlated with memory functioning in either age group. Retrieval of within-event associations showed a significant level of dependency, which did not differ as a function of reference condition or likelihood category. These findings highlight the ways in which self-reference and prior knowledge improve relational memory, and suggest that the advantage of self-reference is not attributable to increased dependence of elements within complex events.

Aging adults experience declines in working memory and episodic memory, however, it is unclear how these declines operate over time. Decreased working memory may be associated with early changes in episodic memory, by reducing older adults' ability to meaningfully integrate new information into pre-existing schemas and recall information without the assistance of cues. Given the increased prevalence of Alzheimer's disease, and concerns based on subjective memory changes, it is important to understand how these processes interact over time. To assess the relationship between working memory and episodic memory during healthy cognitive aging, we performed neuropsychological assessments at multiple time points in a sample of 310 community-dwelling older adults. Using a cross-lagged panel design, we demonstrated that the lagged associations between working memory and later episodic free recall were 50% larger than the lagged associations between episodic recall and later working memory, suggesting working memory may be a useful metric of future episodic memory decline.

The present study investigated the influence of self-reference on two kinds of relational memory, internal source memory and associative memory, in young and older adults. Participants encoded object-location word pairs using the strategies of imagination and sentence generation, either with reference to themselves or to a famous other (i.e., George Clooney or Oprah Winfrey). Both young and older adults showed memory benefits in the self-reference conditions compared to other-reference conditions on both tests, and the self-referential effects in older adults were not limited by low memory or executive functioning. These results suggest that self-reference can benefit relational memory in older adults relatively independently of basic memory and executive functions.

The present study investigated whether cognitively healthy older adults who are carriers of the ε4 allele of apolipoprotein E, the most prevalent genetic risk factor for late-onset Alzheimer's disease, benefit from self-referential processing and emotional processing to the same degree as noncarriers of this gene. Participants encoded emotional and nonemotional narratives using a baseline-orienting task, semantic elaboration, or imagination-based self-referential processing and then completed a recognition memory test. Both groups of older adults showed enhanced recognition memory for narrative information following self-referential processing relative to semantic elaboration, and the magnitude of this memory effect was not affected by ε4 status. However, older adult ε4 carriers did not show an emotional enhancement effect, whereas older adult ε4 noncarriers did. These results indicate that whereas the self-reference effect is not attenuated in cognitively healthy older adults ε4 carriers, deficits in emotional memory may be an early cognitive marker of abnormal decline.

Objectives: Research suggests that older adults who remain socially active and cognitively engaged have better cognitive function than those who are isolated and disengaged. This study examined the efficacy of learning and using an online social networking website, Facebook.com, as an intervention to maintain or enhance cognitive function in older adults., Method: Forty-one older adults were assigned to learn and use Facebook (n = 14) or an online diary website (active control, n = 13) for 8 weeks or placed on a waitlist (n = 14). Outcome measures included neuropsychological tests of executive functions, memory, and processing speed and self-report questionnaires about social engagement., Results: The Facebook group showed a significant increase in a composite measure of updating, an executive function factor associated with complex working memory tasks, compared to no significant change in the control groups. Other measures of cognitive function and social support showed no differential improvement in the Facebook group., Discussion: Learning and using an online social networking site may provide specific benefits for complex working memory in a group of healthy older adults. This may reflect the particular cognitive demands associated with online social networking and/or the benefits of social engagement more generally., (© The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Functional neuroimaging has revealed that in healthy adults retrieval of personal trait knowledge is associated with increased activation in the medial prefrontal cortex (mPFC). Separately, neuropsychology has shown that the self-referential nature of memory can be disrupted in individuals with mPFC lesions. However, it remains unclear whether damage to the mPFC impairs retrieval of personal trait knowledge. Therefore, in this neuropsychological case study we investigated the integrity of personal trait knowledge in J.S., an individual who sustained bilateral damage to the mPFC as a result of an anterior communicating artery aneurysm. We measured both accuracy and consistency of J.S.'s personal trait knowledge as well as his trait knowledge of another, frequently seen person, and compared his performance to a group of healthy adults. Findings revealed that J.S. had severely impaired accuracy and consistency of his personal trait knowledge relative to control participants. In contrast, J.S.'s accuracy and consistency of other-person trait knowledge was intact in comparison to control participants. Moreover, J.S. showed a normal positivity bias in his trait ratings. These results, albeit based on a single case, implicate the mPFC as critical for retrieval of personal trait knowledge. Findings also cast doubt on the likelihood that the mPFC, in particular the ventral mPFC, is necessary for storage and retrieval of trait knowledge of other people. Therefore, this case study adds to a growing body of evidence that mPFC damage can disrupt the link between self and memory., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

There is strong evidence that hippocampal memory returns to a labile state upon reactivation, initiating a reconsolidation process that restabilizes it and allows for its updating. Normal aging is associated with deficits in episodic memory processes. However, the effects of aging on memory reconsolidation and its neural substrate remain largely unknown, and an animal model is lacking. In this study we investigated the effects of aging on context-dependent reconsolidation using an episodic set-learning task in humans and an analogous set-learning spatial task in rats. In both tasks, young and older subjects learned a set of objects (humans) or feeder locations (rats; Set 1) in Context A on Day 1. On Day 2, a different set (Set 2) was learned in either Context A (Reminder condition) or Context B (No Reminder condition). On Day 3, subjects were instructed (humans) or cued (rats) to recall Set 1. Young rats and humans in the Reminder condition falsely recalled significantly more items from Set 2 than those in the No Reminder condition, suggesting that the reminder context triggered a reactivation of Set 1 on Day 2 and allowed the integration of Set 2 items into Set 1. In both species, older subjects displayed a different pattern of results than young subjects. In aged rats, there was no difference between conditions in the level of falsely recalled Set 2 items (intrusions). Older humans in the No Reminder condition made significantly more intrusions than those in the Reminder condition. Follow-up control experiments in aged rats suggested that intrusions in older animals reflected general interference, independent of context manipulations. We conclude that contextual reminders are not sufficient to trigger memory updating in aged rats or aged humans, unlike in younger individuals. Future studies using this animal model should further our understanding of the role of the hippocampus in memory maintenance and updating during normal aging., (Copyright © 2015 Elsevier Inc. All rights reserved.)

With the population of older adults expected to grow rapidly over the next two decades, it has become increasingly important to advance research efforts to elucidate the mechanisms associated with cognitive aging, with the ultimate goal of developing effective interventions and prevention therapies. Although there has been a vast research literature on the use of cognitive tests to evaluate the effects of aging and age-related neurodegenerative disease, the need for a set of standardized measures to characterize the cognitive profiles specific to healthy aging has been widely recognized. Here we present a review of selected methods and approaches that have been applied in human research studies to evaluate the effects of aging on cognition, including executive function, memory, processing speed, language, and visuospatial function. The effects of healthy aging on each of these cognitive domains are discussed with examples from cognitive/experimental and clinical/neuropsychological approaches. Further, we consider those measures that have clear conceptual and methodological links to tasks currently in use for non-human animal studies of aging, as well as those that have the potential for translation to animal aging research. Having a complementary set of measures to assess the cognitive profiles of healthy aging across species provides a unique opportunity to enhance research efforts for cross-sectional, longitudinal, and intervention studies of cognitive aging. Taking a cross-species, translational approach will help to advance cognitive aging research, leading to a greater understanding of associated neurobiological mechanisms with the potential for developing effective interventions and prevention therapies for age-related cognitive decline.

Executive functions supported by prefrontal cortical (PFC) systems provide essential control and planning mechanisms to guide goal-directed behavior. As such, age-related alterations in executive functions can mediate profound and widespread deficits on a diverse array of neurocognitive processes. Many of the critical neuroanatomical and functional characteristics of prefrontal cortex are preserved in rodents, allowing for meaningful cross species comparisons relevant to the study of cognitive aging. In particular, as rodents lend themselves to genetic, cellular and biochemical approaches, rodent models of executive function stand to significantly contribute to our understanding of the critical neurobiological mechanisms that mediate decline of executive processes across the lifespan. Moreover, rodent analogs of executive functions that decline in human aging represent an essential component of a targeted, rational approach for developing and testing effective treatment and prevention therapies for age-related cognitive decline. This paper reviews behavioral approaches used to study executive function in rodents, with a focus on those assays that share a foundation in the psychological and neuroanatomical constructs important for human aging. A particular emphasis is placed on behavioral approaches used to assess working memory and cognitive flexibility, which are sensitive to decline with age across species and for which strong rodent models currently exist. In addition, other approaches in rodent behavior that have potential for providing analogs to functions that reliably decline to human aging (e.g., information processing speed) are discussed.

The gradual decline of cognitive ability with age, even in the absence of overt brain disease, is a growing problem. Although cognitive aging is a common and feared accompaniment of the aging process, its underlying mechanisms are not well understood and there are no highly effective means to prevent it. Additional research on cognitive aging is sorely needed, and methods that enable ready translation between human subjects and animal models stand to provide the most benefit. Here and in the six companion pieces in this special issue, we discuss a variety of challenges and opportunities for studying cognitive aging across species. We identify tests of associative memory, recognition memory, spatial and contextual memory, and working memory and executive function as cognitive domains that are age-sensitive and amenable to testing with parallel means in both humans and animal models. We summarize some of the important challenges in using animal models to test cognition. We describe unique opportunities to study cognitive aging in human subjects, such as those provided by recent large-scale initiatives to characterize cognition in large groups of subjects across the lifespan. Finally, we highlight some of the challenges of studying cognitive aging in human subjects.

Older adults show elevated false alarm rates on recognition memory tests involving faces in comparison to younger adults. It has been proposed that this age-related increase in false facial recognition reflects a deficit in recollection and a corresponding increase in the use of familiarity when making memory decisions. To test this hypothesis, we examined the performance of 40 older adults and 40 younger adults on a face recognition memory paradigm involving three different types of lures with varying levels of familiarity. A robust age effect was found, with older adults demonstrating a markedly heightened false alarm rate in comparison to younger adults for "familiarized lures" that were exact repetitions of faces encountered earlier in the experiment, but outside the study list, and therefore required accurate recollection of contextual information to reject. By contrast, there were no age differences in false alarms to "conjunction lures" that recombined parts of study list faces, or to entirely new faces. Overall, the pattern of false recognition errors observed in older adults was consistent with excessive reliance on a familiarity-based response strategy. Specifically, in the absence of recollection older adults appeared to base their memory decisions on item familiarity, as evidenced by a linear increase in false alarm rates with increasing familiarity of the lures. These findings support the notion that automatic memory processes such as familiarity remain invariant with age, while more controlled memory processes such as recollection show age-related decline.

Knowledge of oneself is preserved in many memory-impaired individuals with neurological damage. Therefore, cognitive strategies that capitalize on mechanisms related to the self may be particularly effective at enhancing memory in this population. The present study investigated the effect of "self-imagining," imagining an event from a personal perspective, on short and long delayed cued recall in memory-impaired individuals with neurological damage. Sixteen patients intentionally encoded word pairs under four separate conditions: visual imagery, semantic elaboration, other person imagining, and self-imagining. The results revealed that self-imagining led to better performance than other-imagining, semantic elaboration, and visual imagery. Furthermore, the "self-imagination effect" (SIE) was preserved after a 30-min delay and was independent of memory functioning. These findings indicate that self-imagining provides a mnemonic advantage in brain-injured individuals, even those with relatively poor memory functioning, and suggest that self-imagining may tap into mnemonic mechanisms related to the self.

Previous studies have indicated a decreased risk for developing Alzheimer's disease in anti-inflammatory (AI) drug users. Yet few studies have determined whether AI drug use provides a protective effect against normal age-related changes in the brains of older adults. Regional volume changes in gray and white matter were assessed cross-sectionally using optimized voxel-based morphometry in 36 females taking AI drugs as arthritis or pain medication and 36 age- and education-matched female controls. Although mean gray and white matter volume differences between AI drug users and the non-AI group were small, AI drug use interacted with age, such that the non-AI group showed significantly greater age-related volume changes in regions of both gray and white matter compared to the AI drug users. These regions included the superior and medial frontal gyri, middle and inferior temporal gyri, fusiform and parahippocampal gyri, and occipital gray matter as well as temporal, parietal, and midbrain white matter. The results are consistent with the notion that AI drugs provide protection against age-related changes in brain volume. It is possible that inflammation plays a role in volume decreases associated with normal aging, and that suppressing the inflammatory response moderates this decrease., (Copyright © 2009 Elsevier Inc. All rights reserved.)

While an extensive literature is now available on age-related differences in white matter integrity measured by diffusion MRI, relatively little is known about the relationships between diffusion and cognitive functions in older adults. Even less is known about whether these relationships are influenced by the apolipoprotein (APOE) ε4 allele, despite growing evidence that ε4 increases cognitive impairment in older adults. The purpose of the present study was to examine these relationships in a group of community-dwelling cognitively normal older adults. Data were obtained from a sample of 126 individuals (ages 52-92) that included 32 ε4 heterozygotes, 6 ε4 homozygotes, and 88 noncarriers. Two measures of diffusion, the apparent diffusion coefficient (ADC) and fractional anisotropy (FA), were obtained from six brain regions-frontal white matter, lateral parietal white matter, the centrum semiovale, the genu and splenium of the corpus callosum, and the temporal stem white matter-and were used to predict composite scores of cognitive function in two domains, executive function and memory function. Results indicated that ADC and FA differed with increasing age in all six brain regions, and these differences were significantly greater for ε4 carriers compared to noncarriers. Importantly, after controlling for age, diffusion measures predicted cognitive function in a region-specific way that was also influenced by ε4 status. Regardless of APOE status, frontal ADC and FA independently predicted executive function scores for all participants, while temporal lobe ADC additionally predicted executive function for ε4 carriers but not noncarriers. Memory scores were predicted by temporal lobe ADC but not frontal diffusion for all participants, and this relationship was significantly stronger in ε4 carriers compared to noncarriers. Taken together, age and temporal lobe ADC accounted for a striking 53% of the variance in memory scores within the ε4 carrier group. The results provide further evidence that APOE ε4 has a significant impact on the trajectory of age-related cognitive functioning in older adults. Possible mechanisms are discussed that could account for the associations between ε4, diffusion, and cognitive function, including the influence of ε4 on neural repair, oxidative stress, and the health of myelin-producing oligodendroglia., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Objective: The ability to imagine an elaborative event from a personal perspective relies on several cognitive processes that may potentially enhance subsequent memory for the event, including visual imagery, semantic elaboration, emotional processing, and self-referential processing. In an effort to find a novel strategy for enhancing memory in memory-impaired individuals with neurological damage, we investigated the mnemonic benefit of a method we refer to as self-imagining-the imagining of an event from a realistic, personal perspective., Method: Fourteen individuals with neurologically based memory deficits and 14 healthy control participants intentionally encoded neutral and emotional sentences under three instructions: structural-baseline processing, semantic processing, and self-imagining., Results: Findings revealed a robust "self-imagination effect (SIE)," as self-imagination enhanced recognition memory relative to deep semantic elaboration in both memory-impaired individuals, F(1, 13) = 32.11, p < .001, η2 = .71; and healthy controls, F(1, 13) = 5.57, p < .05, η2 = .30. In addition, results indicated that mnemonic benefits of self-imagination were not limited by severity of the memory disorder nor were they related to self-reported vividness of visual imagery, semantic processing, or emotional content of the materials., Conclusions: The findings suggest that the SIE may depend on unique mnemonic mechanisms possibly related to self-referential processing and that imagining an event from a personal perspective makes that event particularly memorable even for those individuals with severe memory deficits. Self-imagining may thus provide an effective rehabilitation strategy for individuals with memory impairment.

Little is known about the effect of obesity on brain structures and cognition in healthy older adults. This study examined the association between body mass index (BMI), regional volume differences in gray and white matter measured by magnetic resonance imaging (MRI), and cognitive functioning in older females. Participants included 95 community-dwelling older females (ages 52-92 years) who underwent extensive neuropsychological testing and high-resolution MRI scanning. Optimized voxel-based morphometry techniques were employed to determine the correlation between BMI and regional gray and white matter volumes. Volumes of significant regions were then correlated with cognitive functioning. Higher BMI was associated with decreased gray matter volumes in the left orbitofrontal, right inferior frontal, and right precentral gyri, a right posterior region including the parahippocampal, fusiform, and lingual gyri, and right cerebellar regions, as well as increased volumes of white matter in the frontal, temporal, and parietal lobes, even when hypertension was considered. Compared to normal weight women, obese women performed poorer on tests of executive functioning. Smaller gray matter volume in the left orbitofrontal region was associated with lower executive functioning. Additionally, despite the lack of significant group differences in memory and visuomotor speed, gray and white matter volumes predicted performance on these measures. The results provide additional evidence for a negative link between increased body fat and brain functioning in older females., ((c) 2009 Wiley-Liss, Inc.)

Time-based prospective memory (PM) has been found to be negatively affected by aging, possibly as a result of declining frontal lobe (FL) function. Despite a clear retrospective component to PM tasks, the medial temporal lobes (MTL) are thought to play only a secondary role in successful task completion. The present study investigated the role of the FLs and MTLs in time-based PM, as well as their involvement in clock monitoring, plan generation, and time estimation, each of which may play a role in the execution of time-based PM tasks. Based upon their scores on composite measures of FL and MTL function, 32 older adults were divided into four groups, and were then tested on a time-based laboratory PM task. Overall age effects were also assessed and each of the four groups was compared to a group of 32 younger adults. High-frontal functioning participants demonstrated better prospective memory than low-frontal functioning participants, and were not distinguishable from younger adults. Older adults with high-MTL scores performed significantly better than those with low-MTL scores, but only if they were also high in FL function. FL function, but not MTL function, predicted patterns of clock monitoring, quality of plans generated to assist in time-based PM performance, and the accuracy of time estimation. Again, on each of these measures the performance of the high-frontal group was equivalent to that of the younger adults. The results of this study suggest that it is not aging per se that disrupts PM performance, but it is instead primarily the diminished frontal function seen in a subset of older adults.

The most extensively described pathological abnormality in Parkinson's disease (PD) is loss of dopaminergic neurons in the substantia nigra pars compacta and the ventral tegmental area, with degeneration of their striatal terminals. Because of the intimate connections between the striatum and the frontal lobes, individuals with PD often demonstrate impairments on those tasks relying on the prefrontal cortex (e.g., tests of executive functioning). Source memory, or memory for context, is believed to rely on the prefrontal cortex and has been previously associated with executive functioning performance, although it has received little attention in the PD literature. Executive functioning and source memory were measured in a group of nondemented PD patients and healthy control participants. Within the PD group, an anti-Parkinson's medication withdrawal manipulation was used to examine whether source memory was affected by phasic changes in dopamine levels. Compared to healthy control participants, PD patients were impaired in source memory (both on- and off-medication) and on a composite measure of executive functioning. Within the PD group, medication administration improved motor performance but did not have a significant effect on source memory.

The beneficial effects of self-referential processing on memory have been demonstrated in numerous experiments with younger adults but have rarely been studied in older individuals. In the present study we tested young people, younger-older adults, and older-older adults in a self-reference paradigm, and compared self-referential processing to general semantic processing. Findings indicated that older adults over the age of 75 and those with below average episodic memory function showed a decreased benefit from both semantic and self-referential processing relative to a structural baseline condition. However, these effects appeared to be confined to the shared semantic processes for the two conditions, leaving the added advantage for self-referential processing unaffected These results suggest that reference to the self engages qualitatively different processes compared to general semantic processing. These processes seem relatively impervious to age and to declining memory and executive function, suggesting that they might provide a particularly useful way for older adults to improve their memories.

Controversy surrounding dissociative identity disorder (DID) has focused on conflicting findings regarding the validity and nature of interidentity amnesia, illustrating the need for objective methods of examining amnesia that can discriminate between explicit and implicit memory transfer. In the present study, the authors used a cross-modal manipulation designed to mitigate implicit memory effects. Explicit memory transfer between identities was examined in 7 DID participants and 34 matched control participants. After words were presented to one identity auditorily, the authors tested another identity for memory of those words in the visual modality using an exclusion paradigm. Despite self-reported interidentity amnesia, memory for experimental stimuli transferred between identities. DID patients showed no superior ability to compartmentalize information, as would be expected with interidentity amnesia. The cross-modal nature of the test makes it unlikely that memory transfer was implicit. These findings demonstrate that subjective reports of interidentity amnesia are not necessarily corroborated by objective tests of explicit memory transfer., (Copyright (c) 2008 APA, all rights reserved.)

Source memory has consistently been associated with prefrontal function in both normal and clinical populations. Nevertheless, the exact contribution of this brain region to source memory remains uncertain, and evidence suggests that processes used by young and older adults may differ. The authors explored the extent to which scores on composite measures of neuropsychological tests of frontal and medial temporal function differentially predicted the performance of young and older adults on source memory tasks. Results indicated that a frontal composite measure, consistently associated with source memory performance in older adults, was unrelated to source memory in young adults, although it was sensitive to a demanding working memory task. The memory composite score, however, predicted performance in the young group. In addition, item and source memory were correlated in young but not older people. Findings are discussed in terms of age-related differences in working memory and executive functions, and differential binding processes necessary for item and source memory. The requirement to integrate item and source information at encoding appears to place greater demands on executive or working memory processes in older adults than in younger adults., ((c) 2008 APA)

Emotional experiences are easier to remember than neutral ones, but whether memory for all aspects of an experience is improved by emotion remains unclear. Some researchers have argued that the influence of emotion on memory is different for item than for source information, whereas others have argued that emotion affects both similarly. Also, whether item and source memory are affected by emotion in older people in the same way as in young people is currently unclear. We examined item and source memory for emotional and neutral materials in young and older adults. Memory for emotional items was superior to memory for neutral items, whereas there was no difference in source memory. Overall, item and source memory were poorer in older people than in young people, but emotion seemed to have a similar effect on both age groups. Although emotional content was remembered better than neutral content, this benefit did not apply to source memory. However, varying the emotionality of the source (i.e., the voice in Experiment 3) improved memory for the source, and this effect was greater in young than in older people. Tone of voice had no effect on item memory in older people, but the effect was variable in the young and may depend on the extent to which the tone of voice moderates the interpretation of the content.

Flashbulb memories (FMs) are vivid, long-lasting memories for the source of surprising, arousing news. Laboratory studies have consistently found that older adults, especially those with below-average frontal lobe (FL) function, are impaired in source memory relative to young. We tested memory for the source of news concerning the September 11th terrorist attacks in older adults with high or low frontal lobe function and in young people. We found no age differences in source memory a year after the event and no differences related to FL function. Flashbulb memories may be different from usual cases of source memory because of their emotional content, personal importance, or social relevance.

A flashbulb memory (FM) is a vivid, enduring memory for how one learned about a surprising, shocking event. It thus involves memory for the source of event information, as opposed to memory for the event itself. Which brain regions are involved in FM, however, is uncertain. Although medial temporal lobe/diencephalic (MTL/D) damage impairs content or item memory, frontal lobe (FL) damage has been associated with impaired source memory. One would therefore expect that FM should depend on the FLs, although two recent reports do not support this idea. In the current study, we examined memory for the events of September 11th, and memory for the source of that information, in MTL/D patients, FL patients, and healthy subjects. Only the MTL/D patients were impaired in long-term memory for the event itself, measured after a 6 month retention interval. The FL patients, on the other hand, showed a selective deficit in source memory, although their memory for the target event was unimpaired. MTL/D and FL structures appear to play different roles in memory for flashbulb events.

On the basis of their scores on composite measures of frontal and temporal lobe function, derived from neuropsychological testing, seniors were divided preexperimentally into 4 groups. Participants studied a list of unrelated words under full attention and recalled them while concurrently performing an animacy decision task to words, an odd-digit identification task to numbers, or no distracting task. Large interference effects on memory were produced by the animacy but not by the odd-digit distracting task, and this pattern was not influenced by level of frontal or temporal lobe function. Results show associative retrieval is largely disrupted by competition for common representations, and it is not affected by a reduction in general processing resources, attentional capacity, or competition for memory structures in the temporal lobe.

Forty-eight healthy adults aged 65-85 were recruited for structural magnetic resonance scans after an extensive neuropsychological battery that ensured a high degree of variability across the sample in performance on long-term memory tests, and on tests traditionally thought to rely on prefrontal cortex. Gray matter volumes were measured for three gyri in the frontal lobe (superior, middle, inferior), six gyri in the temporal lobe (superior, middle, inferior, fusiform, parahippocampal, and hippocampus), and the occipital lobe. Gray matter volumes declined across the age range evaluated, but with substantial regional variation--greatest in the inferior frontal, superior temporal, and middle temporal gyri but negligible in the occipital lobe. Both memory performance and executive function declined as the number of hyperintense regions in the subcortical white matter increased. Memory performance was also significantly correlated with gray matter volumes of the middle frontal gyrus (MFG), and several regions of temporal neocortex. However, the correlations were all in the negative direction; better memory performance was associated with smaller volumes. Several previous reports of significant negative correlations between gray matter volumes and memory performance are described, so that the possible reasons for this surprising finding are discussed.

Psychogenic fugue is a disorder of memory that occurs following emotional or psychological trauma and results in a loss of one's personal past including personal identity. This paper reports a case of psychogenic fugue in which the individual lost access not only to his autobiographical memories but also to his native German language. A series of experiments compared his performance on a variety of memory and language tests to several groups of control participants including German-English bilinguals who performed the tasks normally or simulated amnesia for the German language. Neuropsychological, behavioral, electrophysiological and functional neuroimaging tests converged on the conclusion that this individual suffered an episode of psychogenic fugue, during which he lost explicit knowledge of his personal past and his native language. At the same time, he appeared to retain implicit knowledge of autobiographical facts and of the semantic or associative structure of the German language. The patient's poor performance on tests of executive control and reduced activation of frontal compared to parietal brain regions during lexical decision were suggestive of reduced frontal function, consistent with models of psychogenic fugue proposed by Kopelman and Markovitsch.

The dual-process model of recognition memory proposed by Jacoby (1991; see also Mandler, 1980) postulates the existence of two independent components of recognition memory: a conscious retrieval process (recollection) and an automatic component (familiarity). Older adults appear to be impaired in recollection, but findings with respect to familiarity have been mixed. Studies of the brain bases of these components, using neurological patients, have also been inconclusive. We examined recollection and familiarity, using the process dissociation procedure, in older adults characterized on the basis of both their frontal and their medial temporal lobe function. Findings suggest that only some older adults, depending on their neuropsychological status, are impaired in recollection and/or familiarity: Recollection seems to involve both frontal and medial temporal lobe function, whereas familiarity appears to be dependent only on function associated with the medial temporal lobes.

Flashbulb memories (FMs) are vivid, stable memories for the reception of arousing, consequential news. Although such memories have been found in people of all ages, in the only examination of age differences to date, Cohen, Conway, and Maylor (1994) reported that older adults were less likely than young adults to experience a FM. We hypothesised that FM would be impaired in older adults with reduced frontal lobe (FL) function. To test this hypothesis, we asked older adults, who had been characterised according to FL function, to recall details of the moment that they first heard the news about the deaths of Princess Diana and Mother Teresa. Long-term retention was tested 6 months later. Details concerning the reception of the news about Princess Diana's death were retained better than those associated with Mother Teresa's death. Importantly, there was no evidence that memory for these contextual details was related to FL function. A measure of medial temporal lobe function, derived from neuropsychological tests of episodic memory, was also not associated with memory for the reception events, although it was associated with memory for the details of an everyday autobiographical event. We speculated that emotionally arousing autobiographical memories may be qualitatively different from everyday memories and may involve the amygdala.

Objective: To determine whether damage to prefrontal cortex is associated with face memory impairment., Background: Neurophysiologic and functional imaging studies suggest that prefrontal cortex is a key component of a distributed neural network that mediates face recognition memory. However, there have been few attempts to examine the impact of frontal lobe damage on face memory performance., Methods: Patients with focal frontal lobe lesions and normal control subjects were administered two-alternative forced-choice and single-probe "yes/no" tests of recognition memory for novel faces. Retrograde memory was assessed by using famous faces as stimuli., Results: Compared with control subjects, patients with frontal lobe lesions showed evidence of marked anterograde and relatively mild retrograde face memory impairment. In addition, patients with right frontal lesions demonstrated increased susceptibility to false recognition, consistent with the breakdown of strategic memory retrieval, monitoring, and decision functions., Conclusions: Prefrontal cortex plays an important role in the executive control of face memory encoding and retrieval. Left and right prefrontal regions seem to make different contributions to recognition memory performance.

Source memory has been found to be more affected by aging than item memory, possibly because of declining frontal function among older adults. In 4 experiments, the authors explored the role of the frontal lobes (FLs) in source memory, the extent to which they may be involved in the encoding and/or retrieval of source or context, and the conditions under which the source memory deficit in older people may be reduced or eliminated. Results indicated that only a subset of older adults show deficits in source memory, namely those with below average frontal function, and these deficits can be eliminated by requiring people at study to consider the relation between an item and its context. These results provide convincing evidence of the importance of frontal function during the encoding of source and suggest that older adults with reduced FL function fail to initiate the processes required to integrate contextual information with focal content during study.

To examine the neuropsychology of prospective remembering, older adults were divided preexperimentally into 4 groups on the basis of their scores on 2 composite measures: one assessing frontal lobe function and the other assessing medial temporal lobe function. The groups reflected the factorial combination of high and low functioning for each neuropsychological system, and they were tested on an event-based laboratory prospective memory task. High-functioning frontal participants showed better prospective remembering than low-functioning frontal participants. There was no significant difference in prospective memory performance attributable to medial temporal functioning. The results support the theoretical notion that frontal lobe processes play a key role in prospective remembering. Discussion focuses on the particular components of prospective memory performance that frontal lobes might mediate.

Objective: The objective of this study was to contrast overt verbal versus covert autonomic responses to facial stimuli in a patient with false recognition following frontal lobe damage., Background: False recognition has been linked to frontal lobe dysfunction. However, previous studies have relied exclusively on overt measures of memory and have not examined whether or not patients with false recognition continue to demonstrate preserved covert discrimination of familiar and unfamiliar items., Methods: We recorded skin conductance responses (SCRs) in a patient with frontal lobe damage and in normal control subjects while they performed a familiarity decision task using famous and unfamiliar faces as stimuli., Results: Patient J.S. produced significantly more overt false recognition errors and misidentifications in response to unfamiliar faces than control subjects. However, similar to the control subjects, he showed accurate covert autonomic discrimination of truly familiar faces from unfamiliar ones. Furthermore, SCRs to falsely recognized unfamiliar faces were not significantly different from SCRs generated to unfamiliar faces that J.S. correctly rejected., Conclusions: Our findings provide further neuropsychological evidence that overt and covert forms of face recognition memory are dissociable. In addition, the failure to detect an autonomic correlate for the false recognition errors and misidentifications in J.S. suggests that these memory distortions were not related to the spurious activation of stored memory representations for specific familiar faces. Instead, these incorrect responses may have been driven by the sense of familiarity evoked by novel faces that had a general resemblance to faces encountered previously. We propose that false recognition in J.S. resulted from the breakdown of strategic frontal memory retrieval, monitoring, and decision functions critical for attributing the experience of familiarity to its appropriate source.

Two experiments investigated semantic priming effects in a modified version of the Dagenbach, Carr, and Barnhardt (1990) rare-word paradigm. After learning a list of rare words to a criterion of 50% recall, subjects participated in a lexical decision task in which the rare words served as primes. When the targets were associatively related to the primes, lexical decision responses were facilitated following recalled definitions and inhibited following unrecalled definitions. When the targets were synonyms of the rare words, facilitation occurred following both recalled and unrecalled definitions. The results were interpreted as supporting a center-surround model of attentional retrieval that may serve an adaptive role in new learning.

The purpose of this study was to compare a mnemonic strategy based on concept-drive processing and explicit memory (i.e., verbal elaboration and imagery) to one based on data-driven processing and implicit memory (the method of vanishing cues) in a names and faces learning task. A third training condition that used video presentation was also included. Six American and six German patients with memory impairment attributable to brain injuries of different etiologies attempted to learn the associations between names and faces in each of the three conditions. The mnemonic strategy proved to be the most effective. Discussion focuses on the characteristics of the training procedures and on the nature of the to-be-learned materials as critical determinants of the effectiveness of different training techniques.

Previous research has produced conflicting evidence concerning transfer of new learning by amnesic patients. The present experiment investigated the hypothesis that different numbers of learning trials account for differences in transfer, such that the greater the number of repetitions of material in identical stimulus contexts the poorer the transfer. Six memory-impaired patients and six control subjects attempted to learn the names of business-related documents in response to descriptive definitions. Learning continued until one of the following criteria was reached: 50% correct, 100% correct, 100% correct plus 10 trials. In a transfer task, subjects were then asked to produce the target responses to altered definitional cues. The results of the experiment demonstrated that, contrary to prediction, transfer improved with numbers of learning trials. Results are consistent with the view that continued study of information allows better integration of new learning with prior knowledge and correspondingly higher levels of transfer. The theoretical implications of the findings are discussed in terms of the declarative/procedural and the episodic/semantic memory distinction. It is suggested that memory-impaired patients are capable of acquiring new semantic information although not at a normal rate. Implications for memory rehabilitation are also outlined.

Previous research demonstrated that a single amnesic patient could acquire complex knowledge and processes required for the performance of a computer data-entry task. The present study extends the earlier work to a larger group of brain-damaged patients with memory disorders of varying severity and of various etiologies and with other accompanying cognitive deficits. All patients were able to learn both the data-entry procedures and the factual information associated with the task. Declarative knowledge was acquired by patients at a much slower rate than normal whereas procedural learning proceeded at approximately the same rate in patients and control subjects. Patients also showed evidence of transfer of declarative knowledge to the procedural task, as well as transfer of the data-entry procedures across changes in materials.

Several investigators have suggested that microcomputers might serve as useful external aids for memory-impaired patients. However, knowledge of basic computer vocabulary may be necessary for patients to use and benefit from a microcomputer. The present paper describes a procedure, the method of vanishing cues, which facilitated the acquisition of computer-related vocabulary in four memory-impaired patients. The method involves the systematic reduction of letter fragments of to-be-learned words across trials. Although learning was slow and strongly dependent on first-letter cues, all patients acquired a substantial amount of the vocabulary and eventually were able to produce the target words in the absence of fragment cues. Further, they retained the vocabulary over a 6-week interval and showed some transfer of the knowledge they had acquired. These findings suggest that memory-impaired patients may eventually be able to use a microcomputer as a prosthetic device.

Several investigators have shown that memory-impaired patients are capable of learning relatively simple information in both the laboratory and everyday life. The present research explored whether patients with memory disorders could also acquire complex knowledge--the domain-specific knowledge needed for operating and interacting with a microcomputer. The results indicated that patients with memory disorders of varying severity could learn to manipulate information on the computer screen, to write, edit and execute simple computer programs, and to perform disk storage and retrieval operations. The learning process, however, was slow relative to controls and the knowledge acquired appeared to be qualitatively different. Theoretical and practical implications of these findings are discussed.

This study explored the limits of learning that could be achieved by an amnesic patient in a complex real-world domain. Using a cuing procedure known as the method of vanishing cues, a severely amnesic encephalitic patient was taught over 250 discrete pieces of new information concerning the rules and procedures for performing a task involving data entry into a computer. Subsequently, she was able to use this acquired knowledge to perform the task accurately and efficiently in the workplace. These results suggest that amnesic patients' preserved learning abilities can be extended well beyond what has been reported previously.

Previous research has demonstrated that patients with memory disorders resulting from closed-head injury can acquire the complex knowledge and skills necessary for the use of a microcomputer. The present paper extends the generality of those findings by showing that (1) amnesic patients with other etiologies could similarly learn how to operate a computer and (2) the knowledge and skills acquired were retained over intervals of up to 9 months.

This experiment investigated the durability of implicit memory for a single episode in normal and amnesic subjects. The target materials consisted of sentence puzzles that were difficult to comprehend in the absence of a key word or phrase. Sentences were re-presented at delays ranging from one minute to one week, and implicit memory was indicated by facilitation in solving previously incomprehensible sentences on subsequent exposures. Patients with severe memory impairments on tests of explicit recall and recognition showed substantial and robust facilitation, or priming, from a single prior presentation and there was no evidence of a systematic decay of facilitation over retention intervals up to one week. The long-lasting implicit memory observed in the sentence puzzle task contrasts with previous findings of rapid decay of priming effects in amnesic patients.