Exercise mode and executive function in older adults: An ERP study of task-switching

The purpose of this study was to investigate the relationship between exercise mode and executive function and its effect on behavior and neuroelectric activity. Forty-eight older adults were classified into open-skill, closed-skill, and irregular exercise groups based on their experience of exercise participation. Executive function was measured via a task-switching paradigm, in which the behavioral indices and event-related potentials elicited by task-switching were assessed. The results revealed that the exercise groups, regardless of the exercise mode, exhibited faster reaction times in both global and local switches than the irregular exercise group, regardless of the within-task conditions. Similarly, larger P3 amplitudes were observed in both exercise groups compared to the irregular exercise group. Moreover, additional facilitation effects of open-skill exercises on global switch costs were observed, whereas no differences in local switch costs were found among the three groups. The results replicate previous studies that have reported generally improved executive function after participation in exercises; additionally, they extend the current knowledge by indicating that these cognitive improvements in specific aspects of executive function could also be obtained from open-skill exercises.     

Random noun generation in younger and older adults

We examined age-related changes of executive functions by means of random noun generation. Consistent with previous observations on random letter generation, older participants produced more prepotent responses than younger ones. In the case of random noun generation, prepotent responses are nouns of the same category as the preceding noun. In contrast to previous observations, older participants exhibited stronger repetition avoidance and a stronger tendency toward local evenness—that is, toward equal frequencies of the alternative responses even in short subsequences. These data suggest that at higher adult age inhibition of prepotent responses is impaired. In addition, strategic attentional processes of response selection are strengthened, in particular the application of a heuristic for randomness. In this sense response selection is more controlled in older than in younger adults.     

Phenomenological characteristics of emotional memories in younger and older adults

Older adults sometimes show a “positivity effect” in memory, remembering proportionally more positive information than younger adults. Using a modified Memory Characteristics Questionnaire, this study examined whether emotional valence impacts the phenomenological qualities of young and older adults’ memories. Ageing did not impact the effect of valence on the qualities of high-arousal memories. However, ageing sometimes impacted subjective memory for details of low-arousal memories: In Experiment 2, older adults reported remembering more thoughts, feelings, and temporal order details about positive low-arousal stimuli, while young adults’ ratings for those dimensions were higher for negative low-arousal stimuli. These findings suggest that valence most readily affects the qualities of young and older adults’ emotional memories when those memories are low in arousal.     

Measuring experiential well-being among older adults

ABSTRACT

Experienced well-being measures tap a distinct form of subjective well-being (SWB) and have different age-related properties than the more widely studied evaluations of life satisfaction. Unlike evaluations of the quality of life as a whole, experiential measures capture affective reactions soon after they occur. Recent advances in measurement have allowed for the inclusion of such experiential measures even in large-scale studies. However, respondent burden remains a concern; hence, surveys have also employed shorter experiential modules. The psychometric properties of these brief measures are not well understood. We examine the psychometric characteristics, including the factor structure and correlations with theoretically relevant criteria, of experienced wellbeing measures included in two supplements to the Panel Study of Income Dynamics (PSID). The first supplement included a detailed time diary whereas the second included a brief review of the prior day. Results show that for the detailed time diaries a single index of affective experience provides a useful summary of the associations among individual affect items, both within and between participants. For the abbreviated method, two or more subscales better describe the underlying structure.     

Depression and sleep quality in older adults: a meta-analysis

The literature emphasizes depression and poor sleep quality as problems that affect many elderly individuals. However, these problems have been related in few studies and there is no meta-analysis performed so far on this relationship. The present research reviewed the studies performed on the subjective sleep quality in order to understand how it relates to depression in older adults. The review was conducted in January 2016 and comprised publications between 2005 and 2015. Based on the electronic databases Web of Science and EBSCO, we used the keywords ‘sleep quality’, ‘depression’, and ‘older’ to identify the empirical studies performed. After assessing the collected studies, we selected those that presented the elderly as participants, resulting in nine papers (N = 3069). A random-effects method was used to evaluate the relationship between depression and sleep. We found that an older person’s lack of good sleep quality is significantly related with depression. The main limitation of this study was the difficulty in collecting a greater number of studies. Future research should consider the importance of additional variables (e.g. moderators) in order to understand and investigate viable interventions for prevention and health promotion in the elderly.     

A bilingual advantage for episodic memory in older adults

The ability to remember events—referred to as episodic memory—is typically subject to decline in older adulthood. Episodic memory decline has been attributed in part to less successful executive functioning, which may hinder an older adult's ability to implement controlled encoding and retrieval processes. Since bilingual older adults often show more successful executive functioning than monolinguals, they may be better able to maintain episodic memory. To examine this hypothesis, we compared bilingual and monolingual older adults on a picture scene recall task (assessing episodic memory) and a Simon task (assessing executive functioning). Bilinguals exhibited better episodic memory than their monolingual peers, recalling significantly more items overall. Within the bilingual group, earlier second language acquisition and more years speaking two languages were associated with better recall. Bilinguals also demonstrated higher executive functioning, and there was evidence that level of executive functioning was related to memory performance. Results indicate that extensive practice controlling two languages may benefit episodic memory in older adults.     

Effects of execution duration on within-item strategy switching in young and older adults

This study aimed at determining whether previously found age-related differences in within-item strategy switching is modulated by duration of engagement in initial strategy execution. In a computational estimation task, young and older adults had to find estimates to arithmetic problems like 37×64 while either rounding down (i.e., 30×60) or rounding up (i.e., 40×70) both operands to the closest decades. Participants were asked to execute a cued strategy for different durations (i.e., 1, 2, or 3 s), before deciding whether the cued strategy was the best strategy and to switch to the best strategy if the cued strategy was not the best. The main findings revealed that (1) young and older adults were able to switch strategies, especially when they started to execute poorer strategy on a given item; (2) older adults switched strategy less often than young adults, and (3) both young and older participants switched strategy less frequently for long than for short durations. These findings suggest that to be able to switch strategy within item, participants should not be too much engaged in execution of the initially selected strategy, and that duration of engagement in initial strategy execution does not modulate age-related differences in within-item strategy execution.     

Social relevance enhances memory for impressions in older adults

Previous research has demonstrated that older adults have difficulty retrieving contextual material over items alone. Recent research suggests this deficit can be reduced by adding emotional context, allowing for the possibility that memory for social impressions may show less age-related decline than memory for other types of contextual information. Two studies investigated how orienting to social or self-relevant aspects of information contributed to the learning and retrieval of impressions in young and older adults. Participants encoded impressions of others in conditions varying in the use of self-reference (Experiment 1) and interpersonal meaningfulness (Experiment 2), and completed memory tasks requiring the retrieval of specific traits. For both experiments, age groups remembered similar numbers of impressions. In Experiment 1 using more self-relevant encoding contexts increased memory for impressions over orienting to stimuli in a non-social way, regardless of age. In Experiment 2 older adults had enhanced memory for impressions presented in an interpersonally meaningful relative to a personally irrelevant way, whereas young adults were unaffected by this manipulation. The results provide evidence that increasing social relevance ameliorates age differences in memory for impressions, and enhances older adults’ ability to successfully retrieve contextual information.     

The effects of sleep on episodic memory in older and younger adults

Evidence on sleep-dependent benefits for episodic memory remains elusive. Furthermore we know little about age-related changes on the effects of sleep on episodic memory. The study we report is the first to compare the effects of sleep on episodic memories in younger and older adults. Memories of stories and personal events were assessed following a retention interval that included sleep and following an equal duration of wakefulness. Both older and younger adults have superior memory following sleep compared to following wakefulness for both types of material. Amount of forgetting of personal events was less during wakefulness in older adults than in younger adults, possibly due to spontaneous rehearsal. Amount of time spent sleeping correlated highly with sleep benefit in older adults, suggesting that quantity of total sleep, and/or time spent in some stages of sleep, are important contributors to age-related differences in memory consolidation or protection from interference during sleep.     

The effects of dual-tasking on arm muscle responses in young and older adults

This study examined whether dual-tasking affects an individual’s ability to generate arm muscle responses following a loss of balance. Nineteen young and 16 older adults recovered their balance in response to a surface translation. This balance task was either completed on its own or while counting backwards by 2’s (easy counting difficulty) or 7’s (hard counting difficulty). With increasing counting difficulty, less attentional resources were assumed to be available for balance recovery. The ability to generate arm muscle responses was quantified through the measurement of electromyographic (EMG) onset latencies and amplitudes from three arm muscles. Results indicated that the attentional requirements of the counting task did not greatly affect EMG onset latencies or amplitudes for both young and older adults. Even when an effect was observed, the magnitude of change was small (e.g., ∼3 ms earlier EMG onset and ∼2.0%MVC smaller EMG amplitude during the dual- compared to the single-task conditions). Thus, the generation of arm muscle responses do not appear to require a significant amount of attentional resources and the decreased ability to cope with cognitive interference with ageing is unlikely to explain why older adults have difficulty in generating arm responses following a loss of balance.     

Aging and prejudice: Diminished regulation of automatic race bias among older adults

A popular view holds that older adults are more prejudiced than younger adults because they grew up in a less tolerant era. An alternative view proposes that aging corresponds with stronger prejudice among older adults because they have reduced capacity to inhibit biased associations that come to mind automatically. To independently assess these possibilities, we modeled the processes underlying implicit racial attitudes in samples of teenagers through people in their nineties. Results indicated that older adults showed greater implicit bias because they were less able to regulate the automatic associations they possessed, not because of holding stronger associations in the first place. These findings suggest that age-related increases in racial biases, even those that are implicit, may be due to self-regulatory failure of older adults, rather than to cohort effects.     

Effortful semantic decision-making boosts memory performance in older adults

A major concern in age-related cognitive decline is episodic memory (EM). Previous studies indicate that both resource and binding deficits contribute to EM decline. Environmental support by task manipulations encouraging stronger cognitive effort and deeper levels of processing may facilitate compensation for these two deficits. To clarify factors that can counteract age-related EM decline, we assessed effects of cognitive effort (four levels) and level of processing (LoP, shallow/deep) during encoding on subsequent retrieval. Young (YAs, N?=?23) and older (OAs, N?=?23) adults performed two incidental encoding tasks, deep/semantic and shallow/perceptual. Cognitive effort was manipulated by varying decision-making demands. EM performance, indexed by d-prime, was later tested using a recognition task. Results showed that regardless of LoP, increased cognitive effort caused higher d-primes in both age groups. Compared to YAs, OAs showed a lower d-prime after shallow encoding across all cognitive effort levels, and after deep encoding with low cognitive effort. Deep encoding with higher levels of cognitive effort completely eliminated these age differences. Our findings support an environmental-compensatory account of cognitive ageing and can have important therapeutic implications.     

Future thinking improves prospective memory performance and plan enactment in older adults

Efficient intention formation might improve prospective memory by reducing the need for resource-demanding strategic processes during the delayed performance interval. The present study set out to test this assumption and provides the first empirical assessment of whether imagining a future action improves prospective memory performance equivalently at different stages of the adult lifespan. Thus, younger (n?=?40) and older (n?=?40) adults were asked to complete the Dresden Breakfast Task, which required them to prepare breakfast in accordance with a set of rules and time restrictions. All participants began by generating a plan for later enactment; however, after making this plan, half of the participants were required to imagine themselves completing the task in the future (future thinking condition), while the other half received standard instructions (control condition). As expected, overall younger adults outperformed older adults. Moreover, both older and younger adults benefited equally from future thinking instructions, as reflected in a higher proportion of prospective memory responses and more accurate plan execution. Thus, for both younger and older adults, imagining the specific visual–spatial context in which an intention will later be executed may serve as an easy-to-implement strategy that enhances prospective memory function in everyday life.     

The structure and correlates of anxiety sensitivity in older adults

Anxiety sensitivity (AS) has been defined as the fear of symptoms of anxiety and panic, and is most frequently assessed with the Anxiety Sensitivity Index (Peterson & Reiss, 1987). To investigate the nature and structure of AS in an older sample, data were collected from a sample of 322 adults aged 65 to 97, with mean age 75. Confirmatory factor analysis indicated a hierarchical structure with three group factors (physical concerns, mental incapacitation concerns, and social concerns), as well as a general factor, consistent with previous investigations. Results suggest that the nature and structure of the AS trait in older adults are highly similar to those of younger adults.     

Subjective cognitive complaint in healthy older adults: Identification of major domains and relation to objective performance

This study analyzed complaints across a range of memory domains in middle-aged and older adults, as well as assessed their relationship with objective cognitive performance and personal characteristics. A total of 115 community-dwelling, healthy adults between the ages of 45 and 87 completed the Self-Evaluation Questionnaire (QAM) and were tested with a comprehensive neuropsychological battery. A principal component analysis identified seven dimensions of complaint. Difficulty inhibiting internal and external sources of interference when learning or remembering something was the main area of complaint and it was correlated with word-list recall and Digit Symbol. We identified complaints related to a set of memory failures that appear to be more detrimental to autonomy and safety. These were correlated with a measure of functional autonomy and might, therefore, indicate more severe difficulties. Overall, this study provides indications regarding the main domains of memory complaints and identifies which complaints are most reflective of objective cognitive problems.     

Executive functions and linguistic performance in SCD older adults and healthy controls

Subjective cognitive decline (SCD) might represent the preclinical phase of Alzheimer’s disease. Given the interest to characterize it, the present study explores (1) if there are differences in lexical retrieval (LexR) and sentence comprehension (SComp) between SCD and matched controls, and (2) the predictive value of demographic variables and executive functions in relation to LexR and SComp in each group. A sample of 135 participants voluntarily took part in this study (66 with SCD). They all completed the Trail Making, the Stroop, the Boston Naming, and the ECCO-Senior tests, as well as verbal fluency tasks (VF). Results show that (1) groups differ in LexR and in inhibition efficiency, and (2) VF is explained by years of formal education, particularly in the control group; SComp in the most complex items seems to rely in different strategies, related to flexibility in controls and to inhibition efficiency in SCD patients.     

Decision-making and feedback sensitivity: A comparison between older and younger adults

This study investigated decision-making and feedback sensitivity in healthy older adults with a new task: the Pictures Decision Task. The study was conducted on 27 older (aged 64–88) and 26 younger adults (aged 25–57) matched for years of education. Results showed that older adults did not show the Jumping to Conclusions bias and that older adults had difficulty learning from feedback only when the context was ambiguous and not when they were given aids or interpretative information that decreased ambiguity. The Pictures Decision Task, with respect to the Iowa Gambling Task and the Wisconsin Card Sorting Test, allowed us to assess decision-making and feedback sensitivity under highly ambiguous conditions and therefore to add new insight into the reasoning process of older people.     

Stereotype threat reduces false recognition when older adults are forewarned

Exposing older adults to ageing stereotypes can reduce their memory for studied information—a phenomenon attributed to stereotype threat—but little is known about stereotype effects on false memory. Here, we assessed ageing stereotype effects on the Deese-Roediger-McDermott false memory illusion. Older adults studied lists of semantically associated words, and then read a passage about age-related memory decline (threat condition) or an age-neutral passage (control condition). They then took a surprise memory test with a warning to avoid false recognition of non-studied associates. Relative to the control condition, activating stereotype threat reduced the recognition of both studied and non-studied words, implicating a conservative criterion shift for associated test words. These results indicate that stereotype threat can reduce false memory, and they help to clarify mixed results from prior ageing research. Consistent with the regulatory focus hypothesis, threat motivates older adults to respond more conservatively when error-prevention is emphasised at retrieval.     

Function in context: Why American and Trinidadian young and older adults remember the personal past

Multiple and interacting contextual (culture, life phase) and person-specific predictors (i.e., personality, tendency to think-talk about the past) of the functions of autobiographical memory were examined using the Thinking about Life Experiences Scale. American (N = 174) and Trinidadian (N = 182) young and older adults self-reported how frequently they remembered the personal past to serve self, social and directive functions, how often they thought and talked about their past overall, and completed a measure of trait personality. Independent contextual and person-specific predictors were found for using memory to serve a social-bonding function: Americans, young adults, those higher in extraversion, lower in conscientiousness and individuals who frequently think and talk about the past more often use autobiographical memory for social bonding. Across cultures, younger adults report more frequently using memory to serve all three functions, whereas Trinidadians who think more often about the past compared with those who reflect less often are more likely to use it for self and directive functions. Findings are discussed in terms of the individual's embeddedness in cultural and life phase contexts when remembering.     

Stronger evidence for own-age effects in memory for older as compared to younger adults

Three studies examined whether younger and older adults better recall information associated with their own than information related to another age group. All studies compared young and older adults with respect to incidental memory for previously presented stimuli (Studies 1 and 2: everyday objects; Study 3: vacation advertisements) that had been randomly paired with an age-related cue (e.g., photo of a young or an old person; the word “young” or “old”). All three studies found the expected interaction of participants’ age and age-associated information. Studies 1 and 2 showed that the memory bias for information arbitrarily associated with one's own as compared to another age group was significant for older adults only. However, when age-relevance was introduced in a context of equal importance to younger and older adults (information about vacations paired either with pictures of young or older adults), the memory bias for one's own age group was clearly present for both younger and older adults (Study 3).