Intraindividual reaction time variability predicts prospective memory failures in older adults

This study investigated the relationship between intraindividual variability (IIV) in reaction time and prospective memory errors in older adults using data from the Zurich Longitudinal Study of Cognitive Aging (n = 336 individuals aged 66–81 years). The results indicated that increased IIV measured from independent tasks was associated with a greater proportion of prospective memory errors. These significant findings were not influenced by age and did not vary according to prospective memory cue type. Variability is thought to reflect fluctuations in attentional and executive control and these attentional processes may also impact on prospective memory through failure to detect the target cue. The findings suggest, therefore, that measures of variability may have some potential in the identification of older persons who are more vulnerable to everyday errors such as prospective memory failures.     

Terminal decline of episodic memory and perceptual speed in a biracial population

We compared trajectories of terminal cognitive decline in older Black (n = 3372) and White (n = 1756) persons from a defined population who completed tests of episodic memory and perceptual speed at 3-year intervals for up to 18 years. During a mean of 9.9 years of observation, 1608 Black persons and 902 White persons died. Preterminal decline of episodic memory did not differ by race. Terminal episodic memory decline began earlier in Black persons (mean of 4.3 years before death) than in White persons (mean = 3.9 years) and progressed more slowly. By contrast, terminal decline of perceptual speed began earlier in White persons (mean = 5.0 years) than in Black persons (mean = 4.5 years). Rate of perceptual speed decline was more rapid in White persons than in Black persons in both the preterminal and terminal periods. The results indicate that terminal cognitive decline occurs in Black persons but suggest that the rate of cognitive decline during the terminal period is less rapid in Black persons than in White persons.     

Prospective memory and frontal lobe function

The study sought to examine the role of frontal lobe functioning in focal prospective memory (PM) performance and its relation to PM deficit in older adults. PM and working memory (WM) differences were studied in younger aged (n = 21), older aged (n = 20), and frontal injury (n = 14) groups. An event-based focal PM task was employed and three measures of WM were administered. The younger aged group differed from the other two groups in showing significantly higher scores on PM and on one of the WM measures, but there were no differences at a statistically significant level between the older aged group and the frontal injury groups on any of the memory measures. There were, however, some differences in correlations with a WM measure between groups. It is concluded that there are similarities and differences in the deficits in PM between older adults and patients with frontal lobe injury on focal as well as nonfocal PM tasks.     

Working memory training improvements and gains in non-trained cognitive tasks in young and older adults

Previous studies on working memory training have indicated that transfer to non-trained tasks of other cognitive domains may be possible. The aim of this study is to compare working memory training and transfer effects between younger and older adults (n = 60). A novel approach to adaptive n-back training (12 sessions) was implemented by varying the working memory load and the presentation speed. All participants completed a neuropsychological battery of tests before and after the training. On average, younger training participants achieved difficulty level 12 after training, while older training participants only reached difficulty level 5. In younger participants, transfer to Verbal Fluency and Digit Symbol Substitution test was found. In older participants, we observed a transfer to Digit Span Forward, CERAD Delayed Recall, and Digit Symbol Substitution test. Results suggest that working memory training may be a beneficial intervention for maintaining and improving cognitive functioning in old age.     

Relationship of cognitive strategy use to prospective memory performance in a diverse sample of nondemented older adults with varying degrees of cognitive complaints and impairment

Although older adults typically have better performance on prospective memory (PM) tasks carried out in naturalistic settings, a paucity of research directly assesses older adults’ use of compensatory strategies on such tasks. The current study investigates external memory strategy use during performance of a clinical PM test that features both short-term (in laboratory) and long-term (out of laboratory) subtasks (i.e., the Royal Prince Alfred Prospective Memory Test – RPA-ProMem. Nondemented, community-dwelling older adults (n = 214; mean age = 80.5; 68.2% female; 39.7% non-white) with mild cognitive impairment, subjective cognitive decline, and healthy controls completed the RPA-ProMem while external strategy use was permitted and recorded. Overall, participants utilized external strategies 41% of the time on the RPA-ProMem. Increased utilization of external memory strategies was significantly associated with better PM performance. Additionally, better performance on executive functioning tasks was associated with increased use of external memory strategies. Results are discussed in relation to how memory strategy use can be enhanced to improve everyday memory ability in older adults at risk for dementia.     

Younger and older adults’ prospective memory: the role of delay task difficulty

ABSTRACT

There is mixed evidence on the impact of delay task difficulty on prospective memory (PM) performance and little research has examined this among older adults. The present study examined younger (N = 60) and older (N = 57) adults’ prospective memory (PM) performance after completing an easy or difficult Raven’s matrices task. To assess whether delay difficulty impacted how often participants thought about their PM intention, participants were asked to report on what they thought about during the delay task itself and retrospectively after all tasks were completed. Younger adults outperformed older adults on the PM task; however, delay task difficulty had no impact PM for either age group. Reports of thinking about the intention during the delay task differed by age group depending whether they were online or retrospective, however, overall greater reports of thinking about the intention was positively associated with PM performance.     

Assessing declarative memory in 12-month-old infants: A test – retest reliability study of the deferred imitation task

This study examined whether declarative memory in infants can be reliably assessed using the deferred imitation task. Twenty-four infants at the age of 12 months were given the same deferred imitation task twice within a short period of time (week-to-week assessment). Replicating the results of former studies the second memory test yielded better memory performances on the group level than the first one, indicating a memory benefit as is typically found in older children as well as in adults. Stability of memory performance level was analysed using two indicators, namely test – retest correlations assessing stability of individual memory performances for the whole sample, as well as corrected test – retest correlations using individual consistency scores. Test – retest reliability was highly significant (r = .52, p = .009), as well as corrected test – retest reliability (r = .62, p = .001), thus demonstrating that the individual memory performance level in infants can reliably be assessed using the deferred imitation task.     

Emotional prosody effects on verbal memory in older and younger adults

Prosody, or the way things are said, can modify the meaning of utterances making qualitatively different affective prosodies useful for understanding how auditory affective information is processed and remembered. In this study, we collected behavioral data from 225 younger (M age = 20.8 years, SD = 2.5 years; 119 males) and 225 older adults (M age = 71.6 years, SD = 6.5 years; 119 males) in order to examine age differences in emotional prosody effects on verbal memory. Participants were randomly divided into three subgroups according to different prosody listening conditions (positive, negative, and neutral) and prosody effects on a yes–no recognition memory task were investigated. The results showed how older adults who listened to the story read with a neutral prosody remembered more words than those who listened to the same story with a positive or negative prosody. Younger adults showed no valence effects. Our findings highlighted an age and affective prosody interaction that affects remembering in older adults alone.     

Associations between evaluation anxiety,cognitive interference and performance on working memory tasks

According to Cognitive Interference Theory, evaluation anxiety leads to increased negative off‐task self‐dialogue which then results in diminished cognitive performance. Given that negative off‐task self‐dialogue is primarily verbal, the phonological loop and central executive components of the working memory system should be most affected by evaluation anxiety. Eighty‐eight participants were randomly assigned to receive evaluation anxiety inducing instructions or supportive instructions prior to administration of three tests (Digit Span, Visual Memory Span, and StroopColour‐Word) that measured the phonological loop, visuospatial sketchpad, and central executive components of working memory. Measures of evaluation anxiety and negative off‐task self‐dialogue were obtained during and after testing. Results showed that participants receiving anxiety inducing instructions reported significantly more evaluation anxiety and off‐task self‐dialogue. They also had significantly lower performance on the Digit Span Test and the StroopColour‐Word Test. Negative off‐task self‐dialogue also mediated the relationship between evaluation anxiety and performance on the Digit Span Test. Copyright © 2011 John Wiley & Sons, Ltd.     

Associations of transcranial doppler velocity,age, and gender with cognitive function in children with sickle cell anemia in Nigeria

Children with sickle cell anemia (SCA) have elevated cerebral blood velocity relative to healthy peers. The primary aim of this study was to evaluate the association between cerebral blood velocity, measured by transcranial Doppler (TCD) ultrasound, age, and gender with cognitive function in children with SCA in Nigeria. Eighty-three children (M_age = 9.10, SD = 1.90 years; 55% female) with SCA in Nigeria completed cognitive assessments and a TCD ultrasound. The association between TCD velocity and measures of perceptual reasoning (Raven’s Progressive Matrices), working memory (WISC-IV Digit Span), and executive planning (Tower of London, TOL) were assessed. Results showed that elevated TCD velocity significantly predicted lower scores on TOL Time Violations and Total Problem-Solving Time when controlling for BMI, hemoglobin level, and parent education, suggesting that TCD velocity is related to the efficiency of executive function. Further, age was negatively related to children’s performance on the Ravens Matrices and TOL Total Correct, and boys showed greater deficits on the TOL Total Correct relative to girls. Moderation analyses for gender showed that there was a conditional negative association between TCD velocity and Digit Span for boys, but not for girls. Findings suggest that children with SCA in Nigeria with elevated TCD velocity are at risk for deficits in efficiency of executive planning, and boys with elevated TCD velocity are particularly at increased risk for deficits in auditory working memory. Implications of this study are important for interventions to reduce cerebral blood velocity and the use of TCD in this population.     

Hot and cool executive function in children and adolescents with autism spectrum disorder: Cross-sectional developmental trajectories

The development of executive function (EF) in autism spectrum disorder (ASD) has only been investigated using “cool”-cognitive-EF tasks. Little is known about the development of “hot”-affective-EF and whether it follows a similar developmental pathway. This study employed a cross-sectional developmental trajectories approach to examine the developmental changes in cool (working memory, inhibition, and planning) and hot EF (delay discounting and affective decision-making) of ASD participants (n = 79) and controls (n = 91) relative to age and IQ, shedding more light on the hot–cool EF organization. The developmental trajectories of some aspects of cool EF (working memory and planning) differed significantly as a function of age in ASD participants relative to controls. For both hot EFs, no significant age-related changes were found in either group. These findings extend our understanding regarding the maturation of EF from childhood through adolescence in ASD.     

A comparison of visual working memory and episodic memory performance in younger and older adults

Working memory and episodic memory decline with age. However, as they are typically studied separately, it is largely unknown whether age-associated differences are similar. A task design was developed in which visual working memory and episodic memory performances were measured using the same stimuli, with both tasks involving context binding. A 2-back working memory task was followed by a surprise subsequent recognition memory task that assessed incidental encoding of object locations of the 2-back task. The study compared performance of younger (N=30; M_age=23.5, SD_age=2.9, range=20-29) and older adults (N=29; M_age=72.1, SD_age=6.8, range=62-90). Older adults performed worse than younger adults, without an interaction effect. In younger, but not in older adults, performance on the two tasks was related. We conclude that although age differences (Young>Older) are similar in the working memory and incidental associative memory tasks, the relationship between the two memory systems differs as a function of age group.     

Age differences in perceptions of memory strategy effectiveness for recent and remote memory

We examined whether young and older adults hold different beliefs about the effectiveness of memory strategies for specific types of memory tasks and whether memory strategies are perceived to be differentially effective for young, middle-aged, and older targets. Participants rated the effectiveness of five memory strategies for 10 memory tasks at three target ages (20, 50, and 80 years old). Older adults did not strongly differentiate strategy effectiveness, viewing most strategies as similarly effective across memory tasks. Young adults held strategy-specific beliefs, endorsing external aids and physical health as more effective than a positive attitude or internal strategies, without substantial differentiation based on task. We also found differences in anticipated strategy effectiveness for targets of different ages. Older adults described cognitive and physical health strategies as more effective for older than middle-aged targets, whereas young adults expected these strategies to be equally effective for middle-aged and older target adults.     

Age-specific differences of dual n-back training

Age-related decline in executive functions can be decisive in performing everyday tasks autonomously. Working memory (WM) is closely related to executive functions, and training of WM has yielded evidence toward cognitive plasticity in older adults. The training effects often transfer to untrained tasks and functions. These effects have mostly been shown in processes such as WM and attention, whereas studies investigating transfer to executive functions have been scarce. We trained older adults aged 57–73 years in a WM training task that was reported to be effective in producing transfer in young adults. The training intervention consisted of a dual n-back task including independently processed auditory and visual n-back tasks. We investigated transfer to tasks engaging executive functions, and compared the effects in older adults to those reported in young adults. We found that both training groups improved in the training task. Although the training effect in older adults was smaller than the training effect in young adults, the older adults still showed a notable improvement so that after training they performed on the same level as young adults without training. The older adults also showed transfer to an untrained WM updating task, a result that was in accordance with the findings in young adults; other transfer effects in older adults were lacking. We conclude that although transfer effects were scarce, the present study provides encouraging evidence toward the possibilities to compensate for age-related decline in executive functions by a WM training intervention.     

Time-of-day affects prospective memory differently in younger and older adults

The goal of this study was to investigate the impact of circadian arousal on prospective memory performance as a function of age. We tested a younger (18–34 years) and an older group (56–95 years) of participants on- and off-peak with regard to their circadian arousal patterns in a computer-based laboratory experiment. For the prospective memory task, participants had to press a particular key whenever specific target words appeared in an ongoing concreteness-judgment task. The results showed that prospective memory performance was better on- than off-peak in younger but not older participants. Younger participants consistently outperformed older participants in all conditions. We conclude that prospective remembering underlies time-of-day effects which most likely reflect controlled processes.     

Loss of Financial Capacity in Alzheimer's Disease: The Role of Working Memory

Recent research has demonstrated that loss of financial capacity is a common consequence of Alzheimer's disease (AD). While progressive cognitive decline is a defining feature of AD, the relationship between such decline and loss of financial capacity in AD remains unclear. Working memory may be strongly associated with financial abilities, as many financial tasks require temporary storage and manipulation of numerical and other data. The present study examined the relationship between financial capacity and working memory in AD patients. Participants included 20 AD patients and 23 cognitively intact older controls. Working memory was conceptualized using Baddeley and colleagues' model, which posits that the three components of the working memory system are the visuospatial sketchpad, phonological loop, and central executive system. The present study examined only the latter two components of working memory. Each participant was administered the Financial Capacity Instrument (FCI), an instrument that directly assesses eight domains of financial activity, and the WAIS-III Working Memory subtests (Digit Span, Arithmetic, Letter–Number Sequencing). AD patients as a group performed significantly below controls on the FCI Total Score and on each of the eight FCI domains and working memory subtests. Within the AD group, measures of the central executive component of working memory (WAIS-III Digits Backward, Arithmetic, and Letter-Number Sequencing tests) showed strong correlations with the FCI domains of basic monetary skills, checkbook management, bank statement management, and bill payment and FCI total score, while a measure of the phonological loop component of working memory (WAIS-III Digits Forward) was not significantly correlated with any FCI domains or with the FCI total score. The results suggest that the multiple domains of financial capacity are primarily correlated with the central executive component of working memory.     

Measuring executive function skills in young children in Kenya

Interest in measuring executive function skills in young children in low- and middle-income country contexts has been stymied by the lack of assessments that are both easy to deploy and scalable. This study reports on an initial effort to develop a tablet-based battery of executive function tasks, which were designed and extensively studied in the United States, for use in Kenya. Participants were 193 children, aged 3–6 years old, who attended early childhood development and education centers. The rates of individual task completion were high (65–100%), and 85% of children completed three or more tasks. Assessors indicated that 90% of all task administrations were of acceptable quality. An executive function composite score was approximately normally distributed, despite higher-than-expected floor and ceiling effects on inhibitory control tasks. Children’s simple reaction time (β = –0.20, p = .004), attention-related behaviors during testing (β = 0.24, p = .0005), and age (β = –0.24, p = .0009) were all uniquely related to performance on the executive function composite. Results are discussed as they inform efforts to develop valid and reliable measures of executive function skills among young children in developing country contexts.     

The backward span of the Corsi Block-Tapping Task and its association with the WAIS-III Digit Span

The Corsi Block-Tapping Task measures visuospatial short-term and working memory, but a standardized backward condition is lacking. The authors present a standardized backward procedure that was examined in 246 healthy older adults (ages 50 to 92), comparing the results with the Digit Span subtest of the Wechsler Adult Intelligence Scale--Third Edition. Principal component analysis resulted in a two-factor model, dissociating a verbal and a spatial working-memory factor. Also the Corsi backward is not more difficult than the Corsi forward, in contrast to the Digit Span backward that is more difficult than the Digit Span forward. This may suggest that the Corsi Block-Tapping Task backward task relies on processing within working-memory's slave systems, whereas the Digit Span backward also relies on the central executive component of working memory. Finally, regression-based normative data and cutoff scores for older adults are presented for use in clinical practice.     

An Outcome- and Process-Oriented Examination of a Golf-Specific Secondary Task Strategy to Prevent Choking Under Pressure

The present study examined a new golf-specific secondary task to prevent choking under pressure during golf putting. The study examined skilled (n = 20) and novice (n = 24) golfers on a putting task under high- and low-pressure, while carrying out either a golf-specific or an irrelevant letter generation secondary task to prevent skill-focused attention. Results revealed that both secondary tasks prevented choking under pressure in skilled golfers, but not in novices. Additionally, skilled participants displayed increased movement variability associated with improved performance during secondary task performance. These findings provide support for the viability of the new secondary task technique.