Production and Identification Repetition Priming in AmnesticMild Cognitive Impairment

ABSTRACT

The experiment reported here examined implicit memory function, as measured through repetition priming, in amnestic mild cognitive impairment (MCI) to examine whether impairments exist in this aspect of memory function. Young adults, healthy older controls, Alzheimer's disease patients, and MCI participants were asked to perform two types of implicit memory tests (word stem completion and threshold identification repetition priming tasks), as well as a recognition test for studied items. As expected, young adults performed better than the other participants on the recognition test and the word stem completion task; there was equivalent priming across groups on the word identification task. While both the older control and MCI participants showed lower levels of priming on the word stem completion task relative to the young adults, the magnitude of priming was equivalent for these two groups, and reliably greater than that of the dementia participants. These results suggest that not all aspects of memory function are impaired in MCI relative to healthy aging.     

Influence of divergent and convergent thinking on visuomotor adaptation in young and older adults

Visuomotor adaptation declines in older age. This has been attributed to cognitive impairments. One relevant cognitive function could be creativity, since creativity is implicated as mediator of early learning. The present study therefore evaluates whether two aspects of creativity, divergent and convergent thinking, are differentially involved in the age-dependent decline of visuomotor adaptation.In 25 young and 24 older volunteers, divergent thinking was assessed by the alternative-uses-task (AUT), convergent thinking by the Intelligenz-Struktur-Test-2000 (IST), and sensorimotor-adaptation by a pointing task with 60° rotated visual feedback.Young participants outperformed older participants in all three tasks. AUT scores were positively associated with young but not older participants’ adaptive performance, whereas IST scores were negatively associated with older but not young participants’ adaptive performance. This pattern of findings could be attributed to a consistent relationship between AUT, IST and adaptation; taking this into account, adaptation deficits of older participants were no longer significant.We conclude that divergent thinking supports workaround-strategies during adaptation, but doesn’t influence visuomotor recalibration. Furthermore, the decay of divergent thinking in older adults may explain most of age-related decline of adaptive strategies. When the age-related decay of divergent thinking coincides with well-preserved convergent thinking, adaptation suffers most.     

The influence of the visual surrounding environment in older adults and young adults’ cognitive performance: an alternative paradigm

ABSTRACT

This study investigated how the characteristics of the visual surrounding environment influence older- and young-adults’ cognitive performance. Sixty-four older adults and 64 young adults performed four visual cognitive tasks (attention and memory tasks) in two independent sessions while being exposed to a high-load and a low-load visual surrounding environment. We expected that the high-load environment would hurt the older-adults performance due to typical difficulties in ignoring irrelevant stimuli, whereas no such effect would likely occur for the young-adults whose cognitive abilities are at their best. Overall, our results were consistent with our prediction in three tasks (go/no-go, choice reaction time, and Corsi block-tapping). Additionally, the older adults performed worse than the young adults in all tasks, thus confirming expected age-related differences. Our results are consistent with those obtained when distractors and targets are presented in the same display, now using a paradigm which locates the distractors in the surrounding environment.     

Age differences in moral judgment: Older adults are more deontological than younger adults

In 2 studies, an older and a younger age group morally evaluated dilemmas contrasting a deontological judgment (do not harm others) against a utilitarian judgment (do what is best for the majority). Previous research suggests that deontological moral judgments are often underpinned by affective reactions and utilitarian moral judgments by deliberative thinking. Separately, research on the psychology of aging has shown that affect plays a more prominent role in the judgments and decision making of older (vs. younger) adults. Yet age remains a largely overlooked factor in moral judgment research. Here, we therefore investigated whether older adults would make more deontological judgments on the basis of experiencing different affective reactions to moral dilemmas as compared with younger adults. Results from 2 experiments indicated that older adults made significantly more deontological moral judgments. Mediation analyses revealed that the relationship between age and making more deontological moral judgments is partly explained by older adults exhibiting significantly more negative affective reactions and having more morally idealistic beliefs as compared with younger adults.     

Attentional modulation of masked repetition and categorical priming in young and older adults

Three experiments examined the effects of temporal attention and aging on masked repetition and categorical priming for numbers and words. Participants' temporal attention was manipulated by varying the stimulus onset asynchrony (i.e., constant or variable SOA). In Experiment 1, participants performed a parity judgment task and a lexical decision task in which categorical priming and repetition priming were, respectively, tested. Experiment 2 used a semantic categorization task testing categorical priming. In Experiment 3, repetition and categorical priming were tested in the same semantic categorization task with the same stimuli. The results of the three experiments showed that masked repetition priming is insensitive to manipulations of temporal attention whereas categorical priming is. Furthermore, no differences were found between young and older adults in repetition priming effects, again contrasting with the categorical priming results for which older adults were more sensitive to attentional manipulations than young adults.     

Exercise type relates to inhibitory and error processing functions in older adults

ABSTRACT

This study investigated the association between exercise type and inhibition of prepotent responses and error detection. Totally, 75 adults (M = 68.88 years) were classified into one of three exercise groups: those who were regular participants in open- or closed-skill forms of exercise, and those who exercised only irregularly. The participants completed a Stroop and task-switching tasks with event-related brain potentials (ERPs) recorded. The results revealed that regular exercisers displayed faster reaction times (RTs) in the Stroop task compared with irregular exercisers. The open-skill exercisers exhibited smaller N200 and larger P300a amplitudes in the Stroop task compared with irregular exercisers. Furthermore, the open-skill exercisers showed a tendency of shorter error-related negativity latencies at the task-witching test. The findings suggest that older adults may gain extra cognitive benefits in areas such as inhibition functioning and error processing from participating in open-skill forms of physical exercises.     

Different Effects of Dual Task Demands on the Speech of Young and Older Adults

Abstract

Young and older adults provided language samples in response to elicitation questions while concurrently performing 3 different tasks. The language samples were scored on three dimensions: fluency, grammatical complexity, and content. Previous research has shown that older adults use a restricted speech register that is grammatically less complex than young adults’ and has suggested that this restricted speech register is buffered from the costs of dual task demands. This hypothesis was tested by comparing language samples collected during a baseline condition with those produced while the participants were performing the concurrent tasks. The results indicate that young and older adults adopt different strategies when confronted with dual task demands. Young adults shift to a restricted speech register when confronted with dual task demands. Older adults, who were already using a restricted speech register, became less fluent although the grammatical complexity and informational content of their speech was preserved. Hence, some but not all aspects of older adults’ speech are buffered from dual task demands.     

Everyday tasks impair spatiotemporal variables of gait in older adults with Parkinson's disease

IntroductionAlthough it is known that individuals with Parkinson's disease (PD) have difficulties performing dual-task activities, most of the studies have verified the effect of dual tasks on gait using tasks that are uncommon to perform while walking. However, the realization of tasks involving gait that really represents the daily activities carried out by the participants, allow us to detect real fall risk situations of individuals with PD during their gait.ObjectiveOur aim was to verify the influence of daily-life dual-tasks on gait spatiotemporal variables of the older adults with PD.Methods20 older adults without PD and 20 older adults with PD participated in the study. Gait kinematic was analyzed under three different conditions: walking without dual task, walking carrying bags with weight, and walking talking on the cell phone.ResultsOlder adults with PD presented lower speed (p = .001), cadence (p = .039), and shorter step length (p = .028) than older adults without PD during walking without dual tasks. When walking while carrying bags with weight, older adults with PD had a lower speed (p < .001), cadence (p = .015), shorter step length (p = .008), and greater double support time (p = .021) compared with older adults without PD. During walking while talking on the cell phone, older adults with PD walked with lower speed (p < .001), cadence (p = .013), shorter step length (p = .001) and swing time (p = .013), and increased double support time (p = .008) and support time (p = .014) in relation to older adults without PD.ConclusionDaily-life dual tasks impair the spatiotemporal variables of gait in the older adults with PD, which was most evident during walking talking on the cell phone.     

The effect of aging on the memory enhancement of the survival judgment task

This study investigated whether or not aging affected the benefit of a survival judgment task. Sixteen young adults and 16 older adults participated in this experiment. In the survival task, participants were requested to judge whether a word was necessary or not in a survival situation. In the self‐referent judgment task, participants were requested to judge how easily the word brings to mind an important personal experience. Participants in each condition were presented 18 concrete nouns at 4‐s intervals. Our results showed that even though the survival judgment task enhanced the memory performance in both the young adults and the older adults, the young adults outperformed the older adults in the survival and self‐referent judgment tasks.     

The effects of acute resistance exercise on young and older males' working memory

ObjectivesThe aim of the current study was two-fold: to examine the effects of acute, moderate intensity resistance exercise (RE) on working memory in young and older males, respectively.DesignA two-study approach with a within-subjects design.MethodsStudy 1 recruited 20 young males aged 21–30 years. Participants underwent two experimental sessions, the exercise session and reading session, in a counterbalanced order. The RE protocol included two sets of 10 repetitions at 70% of 10-repetition maximum of eight muscle exercises. The Sternberg working memory paradigm with two probe types (in-set probes and out-of-set probes) was used as the cognitive task where reaction times (RT) and response accuracy were identified. Study 2 recruited 20 older male adults aged 65–72 years. The methods and experimental procedures were the same as Study 1.ResultsIn Study 1, young males demonstrated shorter RTs after the exercise treatment as compared with the reading treatment for both probe types. In Study 2, older males showed shorter RTs after the exercise treatment as compared with the reading treatment in the out-of-set probes only.ConclusionsWhile acute RE benefited working memory in both young and older males, rather than general facilitation, it was shown to have a disproportionately larger effect on older males for tasks involving higher working memory demands.     

Should I Drive Today? Development of a daily driving decisions model for older adults

BackgroundOlder adults in communities make daily decisions about how to meet their transportation needs so they can access services and stay socially connected. With the aging of populations in developed countries, the travel decisions of older adults will have increasing impacts. Research studies have identified different sets of factors that contribute to certain travel decisions, but little research has been directed towards understanding how individuals select information from all available factors, what information they include in their decisions under different circumstances, and the processes they use in making their transportation decisions.MethodsThis exploratory study involved 20 men and 17 women, mean age 78.6 years (range 70–96), who drove weekly. All participants were involved in each phase of the 3-phase study. In Phase 1, a review of the literature and interviews with the participants was used to collect information, and inductive thematic analysis was employed to construct a draft conceptual model of older driver decision-making. In Phase 2, participants completed a stated preference task of written scenarios to demonstrate their decision-making strategies. Results were tabulated and used to refine a final Daily Driving Decisions model. In Phase 3, a card sorting decision task was used to test the model with participants.ResultsThe final dynamic Daily Driving Decisions Model was confirmed to describe decision processes used by the participants in making decisions about how they would meet their transportation needs. The model describes three categories of factors used in decisions, labelled Motivators, Constraint/Enablers and Context, each containing four attribute themes. A significant finding was the variable use of the same item to either constrain or enable the decision to drive depending on the variation of other factors in the scenario. Participants demonstrated use of compensatory and noncompensatory (heuristic, habitual) decision processes that were accommodated by the model.ConclusionThe proposed Daily Driving Decisions Model addresses a gap in our understanding of how older drivers make their decisions about meeting their transportation needs. The model presents a template for classifying the types of information used, ignored or discarded by older adults, and the pathways that they take to arrive at their decisions. The model provides opportunities for further research in testing the influence of other factors such as urban/rural residence, income, health status and culture on driving decisions. Further, the model can be used by practitioners to gain insight into the decision-making behaviours of individuals and to develop interventions to enhance their decision-making skills.     

The psychological nature of subjective memory complaint in non-demented older adults: The respective predictive values of psycho-affective,lifestyle, and cognitive inhibition variables

Introduction/ObjectiveThe aim of this study was to investigate, using path analysis (Lisrel 8.52), the relationships between subjective memory complaint and cognitive inhibition, lifestyle, and psycho-affective variables on a sample of non-demented older adults.MethodOur sample was composed of 109 older adults, who were required to undertake two cognitive inhibition tasks (stroop and verbal fluency) and to respond to scales designed to measure individuals’ psycho-affective status (depression/subjective health) and subjective memory complaint level (Mac Nair). Lifestyle predictors (education and activity levels) were also assessed.Results/ConclusionThis study highlights the importance of adopting a multifactorial approach to the study of subjective memory complaint. In addition to executive variables (verbal fluency task), predictors such as subjective health and activity levels seem to be crucial in our understanding of the psychological nature of subjective memory complaint.     

Type of physical exercise and inhibitory function in older adults: An event-related potential study

ObjectivesThe present study was to examine the relationship between exercise type and inhibitory function in older adults using neuroelectric indices.DesignA cross-sectional design was employed in the present study.MethodSixty adults (M = 69.42 years) were categorized into open-skill, closed-skill, and irregular exercise groups according to their history of exercise participation. The participants conducted a flanker task while their behavioral performance and event-related brain potentials were assessed.ResultsThe results indicated that regular exercisers, regardless of exercise type, exhibited a faster reaction time across conditions of the flanker task compared to irregular exercisers. For the P300 amplitude of the open-skill exerciser group, the peak amplitude was larger at the vertex site compared to the frontal site, whereas no site differences were observed in the closed-skill and irregular exerciser groups.ConclusionsThese findings extend current knowledge by suggesting that, for older adults, participation in physical exercise involving increased cognitive demand is associated with better neural efficiency in resource allocation for tasks that require interference control.     

Task-dependent evaluative processing of moral and emotional content during comprehension: An ERP study

Recently, we showed that when participants passively read about moral transgressions (e.g., adultery), they implicitly engage in the evaluative (good–bad) categorization of incoming information, as indicated by a larger event-related brain potential (ERP) positivity to immoral than to moral scenarios (Leuthold, Kunkel, Mackenzie, & Filik in Social, Cognitive, and Affective Neuroscience, 10, 1021–1029, 2015). Behavioral and neuroimaging studies indicated that explicit moral tasks prioritize the semantic-cognitive analysis of incoming information but that implicit tasks, as used in Leuthold et al. (Social, Cognitive, and Affective Neuroscience, 10, 1021–1029, 2015), favor their affective processing. Therefore, it is unclear whether an affective categorization process is also involved when participants perform explicit moral judgments. Thus, in two experiments, we used similarly constructed morality and emotion materials for which their moral and emotional content had to be inferred from the context. Target sentences from negative vs. neutral emotional scenarios and from moral vs. immoral scenarios were presented using rapid serial visual presentation. In Experiment 1, participants made moral judgments for moral materials and emotional judgments for emotion materials. Negative compared to neutral emotional scenarios elicited a larger posterior ERP positivity (LPP) about 200 ms after critical word onset, whereas immoral compared to moral scenarios elicited a larger anterior negativity (500–700 ms). In Experiment 2, where the same emotional judgment to both types of materials was required, a larger LPP was triggered for both types of materials. These results accord with the view that morality scenarios trigger a semantic-cognitive analysis when participants explicitly judge the moral content of incoming linguistic information but an affective evaluation when judging their emotional content.     

Preliminary investigation of the Kitchen Picture Test (KPT): A new screening test of practical judgment for older adults

Judgment is widely recognized as an important executive function, and deficits in judgment can lead to health risks, safety concerns, and hospitalizations. Surprisingly, relatively few tests of judgment have been developed specifically for older adults—a population particularly vulnerable to executive and functional declines. The Kitchen Picture Test (KPT) is a new screening measure of practical judgment. In two independent studies (Study 1, N = 99 nursing home patients; Study 2, N = 163 nursing home and assisted living patients), psychometric analyses confirmed strong evidence for reliability, construct validity, and predictive validity. A receiver operating characteristic (ROC) curve was calculated from sensitivity and 1-specificity values for diagnoses of dementia versus no dementia. A KPT cut score can be used for identifying persons to be referred to appropriate health-care professionals who have specific expertise in the evaluation and treatment of cognitive impairment.     

Context affects feeling-of-knowing accuracy in younger and older adults

In feeling of knowing (FOK) studies, participants predict subsequent recognition memory performance on items that were initially encoded but that cannot presently be recalled. Research suggests that FOK judgment magnitude may be influenced by the total amount, or quantity, of contextual information retrieved related to the unrecalled target (e.g., Koriat, 1993). The present study examined the contribution of quality of that information to episodic FOK judgments. In addition, we tested whether the episodic FOK deficit demonstrated by older adults could be reduced by encouraging retrieval of contextual information relevant to the target. Three experiments demonstrated that quality of the retrieved partial information influenced FOK judgments in both older and younger adults; however, the manifestation of that influence was age dependent. The results also indicated that older adults required explicit retrieval of contextual information before making FOK judgments in order to make accurate FOK predictions. The results suggest that FOK accuracy may be partially determined by search processes triggered when participants are queried for contextual information.     

Naturalistic assessment of executive function and everyday multitasking in healthy older adults

ABSTRACT

Everyday multitasking and its cognitive correlates were investigated in an older adult population using a naturalistic task, the Day Out Task. Fifty older adults and 50 younger adults prioritized, organized, initiated, and completed a number of subtasks in a campus apartment to prepare for a day out (e.g., gather ingredients for a recipe, collect change for a bus ride). Participants also completed tests assessing cognitive constructs important in multitasking. Compared to younger adults, the older adults took longer to complete the everyday tasks and more poorly sequenced the subtasks. Although they initiated, completed, and interweaved a similar number of subtasks, the older adults demonstrated poorer task quality and accuracy, completing more subtasks inefficiently. For the older adults, reduced prospective memory abilities were predictive of poorer task sequencing, while executive processes and prospective memory were predictive of inefficiently completed subtasks. The findings suggest that executive dysfunction and prospective memory difficulties may contribute to the age-related decline of everyday multitasking abilities in healthy older adults.     

Specific effects of the Trier Social Stress Test on speech fluency in young and older adults

The notion that speech becomes less fluent during stressful speaking conditions has received little empirical test, and no research has tested this relationship in older adult participants. We analyzed speeches produced during the Trier Social Stress Test (TSST) or during a less stressful placebo (pTSST) version of the task. We measured young and older adults’ speech fillers (e.g., um), unfilled pauses (at least 1 s in duration), and other disfluencies (e.g., repetitions, repairs). Neither young nor older adult participants rated themselves as having greater stress in the TSST than pTSST condition, but behavioral effects were obtained. Participants in the TSST condition produced more mid-phrase speech fillers and unfilled pauses than participants in the pTSST condition. Young adults produced more unfilled pauses than older adults overall, and older adults produced more mid-phrase fillers than young adults. Critically, age group interacted with experimental condition, such that older speakers produced disproportionately more mid-phrase fillers than young adults in the TSST compared to the pTSST condition. In sum, the negative effects of the TSST on fluency were generally similar across age, but this specific age-related increase in mid-phrase fillers indicates that older adults’ word retrieval may have been particularly negatively affected. Findings are generally consistent with previous research and add to understanding of how factors internal to the speaker (i.e., demographic, personality, and cognitive variables) and factors external to the speaker (i.e., variables regarding the situation, context, or content of speech) combine to affect speech fluency.     

An emotional Stroop task with faces and words. A comparison of young and older adults

AntecedentsGiven the contradictions of previous studies on the changes in attentional responses produced in aging a Stroop emotional task was proposed to compare young and older adults to words or faces with an emotional valence.MethodThe words happy or sad were superimposed on faces that express the emotion of happiness or sadness. The emotion expressed by the word and the face could agree or not (cued and uncued trials, respectively). 85 young and 66 healthy older adults had to identify both faces and words separately, and the interference between the two types of stimuli was examined.ResultsAn interference effect was observed for both types of stimuli in both groups. There was more interference on positive faces and words than on negative stimuli.ConclusionsOlder adults had more difficulty than younger in focusing on positive uncued trials, whereas there was no difference across samples on negative uncued trials.     

Greater priming for previously distracting information in young than older adults when suppression is ruled out

The use of previously distracting information on memory tests with indirect instructions is usually age-equivalent, while young adults typically show greater explicit memory for such information. This could reflect qualitatively distinct initial processing (encoding) of distracting information by younger and older adults, but could also be caused by greater suppression of such information by younger adults on tasks with indirect instructions. In Experiment 1, young and older adults read stories containing distracting words, which they ignored, before studying a list of words containing previously distracting items for a free recall task. Half the participants were informed of the presence of previously distracting items in the study list prior to recall (direct instruction), and half were not (indirect instruction). Recall of previously distracting words was age-equivalent in the indirect condition, but young adults recalled more distracting words in the direct condition. In Experiment 2, participants performed the continuous identification with recognition task, which captures a measure of perceptual priming and recognition on each trial, and is immune to suppression. Priming and recognition of previously distracting words was greater in younger than older adults, suggesting that the young engage in more successful suppression of previously distracting information on tasks in which its relevance is not overtly signaled.