Event-based prospective memory and executive control of working memory

The effect of verbal praise on prospective memory

Verbal praise is often used to improve prospective memory performance in daily life. According to the motivation cognitive model, the promotional effect of verbal praise on prospective memory may depend largely on redeploying attentional resources, so its promotional effect is likely to be influenced by attention. Two groups of college students (n = 128, n = 117) participated in two experimental studies that examined this hypothesis. Experiment 1 manipulated attention load by changing the difficulty of the ongoing tasks to focus on the effect of verbal praise on prospective memory under different attention load conditions. The results showed that verbal praise promoted prospective memory performance under both attentional load conditions (low, high), but verbal praise mainly promoted the prospective component when the attentional load was low, meanwhile, verbal praise mainly promoted the retrospective component when the attention load was high. Experiment 2 altered the dependence of prospective memory tasks on attentional resources by manipulating the cue focality, further exploring the promotional effect of verbal praise on prospective memory with different types of cues under the low attention load condition. The results showed that verbal praise only promoted prospective memory when non-focal cues were used. The results of this study partially verified the motivation cognitive model.

Relationship Between Future Thinking and Prospective Memory in Alzheimer's Disease

Background

Future thinking and prospective memory are two cognitive processes oriented toward the future and reliant on the ability to envision oneself in future scenarios.

Objective

We explored the connection between future thinking and prospective memory in individuals with Alzheimer's disease (AD).

Methods

We invited both AD participants and control participants to engage in event-based prospective memory tasks (e.g., "please hand me this stopwatch when I inform you there are 10 minutes remaining") and time-based prospective memory tasks (e.g., "close the book you are working on in five minutes"). Additionally, we asked participants to engage in a future thinking task where they imagined upcoming events.

Results

Analysis revealed that AD participants exhibited lower performance in both prospective memory tasks and future thinking compared to the control group. Importantly, we identified significant positive correlations between the performance on event- and time-based prospective memory tasks and future thinking abilities among AD participants.

Conclusions

These findings underscore the connection between the decline in both prospective memory domains and the ability to envision future events in individuals with AD. Our results also shed light on the challenges AD individuals face when trying to project themselves into the future to mentally pre-experience upcoming events.

Ecologically valid virtual reality-based technologies for assessment and rehabilitation of acquired brain injury: a systematic review

Purpose

A systematic review was conducted to examine the state of the literature regarding using ecologically valid virtual environments and related technologies to assess and rehabilitate people with Acquired Brain Injury (ABI).

Materials and methods

A literature search was performed following the PRISMA guidelines using PubMed, Web of Science, ACM and IEEE databases. The focus was on assessment and intervention studies using ecologically valid virtual environments (VE). All studies were included if they involved individuals with ABI and simulated environments of the real world or Activities of Daily Living (ADL).

Results

Seventy out of 363 studies were included in this review and grouped and analyzed according to the nature of its simulation, prefacing a total of 12 kitchens, 11 supermarkets, 10 shopping malls, 16 streets, 11 cities, and 10 other everyday life scenarios. These VE were mostly presented on computer screens, HMD's and laptops and patients interacted with them primarily via mouse, keyboard, and joystick. Twenty-five out of 70 studies had a non-experimental design.

Conclusion

Evidence about the clinical impact of ecologically valid VE is still modest, and further research with more extensive samples is needed. It is important to standardize neuropsychological and motor outcome measures to strengthen conclusions between studies.

Systematic review registration

identifier CRD42022301560, https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=301560.

Effects of virtual reality working memory training on event-based prospective memory in patients with major depressive disorder

BACKGROUND

Event-based prospective memory (EBPM) refers to remembering to perform delayed intention when specific events occur. EBPM deficit is present in patients with major depressive disorder (MDD) and hinders recovery from the illness. Working memory training (WMT) has been reported to enhance EBPM but its effect on EBPM in MDD remains unclear. We investigated whether virtual reality (VR)-based WMT can improve EBPM in MDD patients.

METHODS

Forty-six MDD patients and 41 healthy controls (HC) were recruited. Among the former ones, the first 23 consecutive patients were allocated to the experimental group (MDD-VR) and the next 23 consecutive patients to the waitlist control group (MDD-W). EBPM accuracy was used to assess EBPM performance. Hamilton Depression Rating Scale (HDRS) and Massachusetts General Hospital Cognitive and Physical Functioning Questionnaire (CPFQ) were employed to assess the cognitive functions and the depressive symptoms.

RESULTS

At baseline, EBPM accuracy did not significantly differ between MDD-VR and MDD-W but was lower in both of these two groups than in HC (both p < 0.001). Group-by-time interactions on EBPM accuracy (F = 4.614, p = 0.031) and CPFQ score (F = 5.754, p = 0.021) were present, whereas no significant group-by-time interaction or group effects were observed for HDRS score (both p > 0.05). After VR intervention, MDD-VR showed an increase in EBPM accuracy (Cohen's d = 1.20 [95% CI: 0.53, 1.86], p = 0.001).

CONCLUSIONS

Our results demonstrated that VR-based WMT could improve EBPM deficits in MDD patients. Large-scale studies of a VR-based WMT program are indicated.

Individual differences in working memory capacity predict benefits to memory from intention offloading

Research suggests that individuals with lower working memory have difficulty remembering to fulfil delayed intentions. The current study examined whether the ability to offload intentions onto the environment mitigated these deficits. Participants (N = 268) completed three versions of a delayed intention task with and without the use of reminders, along with three measures of working memory capacity. Results showed that individuals with higher working memory fulfilled more intentions when having to rely on their own memory, but this difference was eliminated when offloading was permitted. Individuals with lower working memory chose to offload more often, suggesting that they were less willing to engage in effortful maintenance of internal representations when given the option. Working memory was not associated with metacognitive confidence or optimal offloading choices based on point value. These findings suggest offloading may help circumvent capacity limitations associated with maintaining and remembering delayed intentions.

Age-related modulation of EEG time-frequency responses in prospective memory retrieval

BACKGROUND

Prospective memory involves remembering to execute an intention at the appropriate moment (prospective component) as well as retrieving the intended action (retrospective component). Several electrophysiological studies showed that neural activity associated with the prospective and the retrospective component differed between older and younger adults. However, these studies mainly reported event-related potentials (ERP), without considering other oscillatory parameters of age-related neural modulations that might be associated with the two components.

OBJECTIVE

In the present study, we analysed electrophysiological data to describe the age-related patterns of brain oscillations associated with the prospective and the retrospective components of prospective memory.

METHODS

The prospective and the retrospective components were manipulated in two experiments. In experiment 1, the prospective component was manipulated by varying the cue distinctiveness (i.e., how easy it was to detect the cue based on colour). In experiment 2, the retrospective component was manipulated by varying the number of intentions to be remembered (i.e., one or two intentions). We used time-frequency analysis to characterise the EEG oscillatory activity in younger and older adults.

RESULTS

The prospective component was associated with age differences in alpha and beta frequency bands. Compared to younger adults, older adults showed a decrease of parietal alpha activity when they detected distinct prospective memory cues, and a decrease of parietal beta when they detected less distinct cues. Moreover, older adults showed less beta activity compared to the younger adults across experimental manipulations. No age differences emerged with respect to the retrospective component.

CONCLUSIONS

The specific pattern of oscillatory activity associated with the prospective component in older adults could underlie the dynamic deployment of different attentional resources supporting cue detection. Moreover, beta activity in both experiments might support an attempt exerted by older adults to enhance task coordination processes. Overall, cluster-based permutation analyses provided a first description of the changes of the EEG time-frequency responses related to intention retrieval in older adults.

Intention to Respond in a Special Way Protects against Forgetting Associations Even When Working Memory Is Occupied

In 2 experiments, subjects engaged in 6 or 7 124-trial blocks of a continuous memory-updating paradigm with study and test trials intermixed. They studied name–location associations and were tested for the location most recently associated with a given name. On study trials, all responses were to be made on a right-hand map. On default test trials, responses were also to be made on the right-hand map, but on special test trials, designated as such during study (by showing the associations in green), responses were to be made on a left-hand map. Both default and special test trials occurred after short (2-back) and long (8-back) retention intervals. In the penultimate (Experiment 1) or last (Experiment 2) block, trials occurred under conditions in which working memory was occupied with a concurrent secondary counting backwards task. Memory for the name–location associations was better with short than with long retention intervals and was better when special (rather than default) responses were to be made, especially at the long retention interval, even with counting backwards. Thus, the intention to respond in a special way protects against forgetting associations, and this protection is not simply due to holding the information from the special trials in working memory.

The impairing effect of acute stress on suppression-induced forgetting of future fears and its moderation by working memory capacity

Unwanted imaginations of future fears can, to some extent, be avoided. This is achieved by control mechanisms similar to those engaged to suppress and forget unwanted memories. Suppression-induced forgetting relies on the executive control network, whose functioning is impaired after exposure to acute stress. This study investigates whether acute stress affects the ability to intentionally control future fears and, furthermore, whether individual differences in executive control predict a susceptibility to these effects. The study ran over two consecutive days. On day 1, the working memory capacity of one hundred participants was assessed. Thereafter, participants provided descriptions and details of fearful episodes that they imagined might happen in their future. On day 2, participants were exposed to either the stress or no-stress version of the Maastricht Acute Stress Test, after which participants performed the Imagine/No-Imagine task. Here, participants repeatedly imagined some future fears and suppressed imaginings of others. Results demonstrated that, in unstressed participants, suppression successfully induced forgetting of the episodes' details compared to a baseline condition. However, anxiety toward these events did not differ. Acute stress was found to selectively impair suppression-induced forgetting and, further, this effect was moderated by working memory capacity. Specifically, lower working memory predicted a susceptibility to these detrimental effects. These findings provide novel insights into conditions under which our capacity to actively control future fears is reduced, which may have considerable implications for understanding stress-related psychopathologies and symptomatologies characterized by unwanted apprehensive thoughts.

Does stress influence the performance of cardiopulmonary resuscitation? A narrative review of the literature

Cardiopulmonary resuscitation represents a major physical and psychological challenge for all involved health care workers because survival of the patients is closely related to the timely and accurate actions of rescuers. Consequently, rescuers may experience high levels of acute mental stress. Stress, in turn, may influence attentional resources and distractibility, which may affect the quality of resuscitation. This narrative review summarizes the current state of research concerning the influence of stress on resuscitation performance. Peer-reviewed studies retrieved in scientific databases were eligible. We found that rescuers experience high levels of stress and some associations of higher levels of stress with lower resuscitation performance. Finally, few interventional studies assessed whether interventions aiming at reducing levels of stress may have a beneficial effect on resuscitation performance, but results are variable. Although the mechanisms linking stress to performance of emergency teams are still not fully understood, factors such as individual experience and self-confidence of rescuers, gender composition and hierarchy within resuscitation teams may play an important role. This review provides a targeted overview of how stress can be defined and measured, how it may influence emergency situations such as a cardiopulmonary resuscitation, and which interventions have the potential to reduce overwhelming stress.

Examining the limits of Memory-Guided Planning in 3- and 4-year olds

Stored memories may be drawn upon when accomplishing goals. In two experiments, we investigated limits on the ability to use episodic memories to support planning in 3- and 4-year-old children. We designed a new memory-guided planning task that required children to both retrieve memories and apply those memories to accomplish multiple, nested goals. We manipulated the difficulty of the task by varying the number of steps required to achieve the goals, and examined the impact of this manipulation on both memory retrieval and planning. We found that, overall, 4-year-olds outperformed 3-year-olds, but as task difficulty increased, all children made more errors. Analysis of these errors suggested that retrieval and planning processes might impose separate limits on memory-guided planning in early childhood, but that these limits may ease across early childhood.

Social commitment toward prospective memory tasks in cognitively impaired non-demented individuals

Prospective memory, which is the ability to remember to perform an intended action in the future, has been found to be diminished in cognitively impaired non-demented individuals (CIND). This study investigated whether providing CIND with a social motive would improve their prospective memory performance. Accordingly, CIND and controls were asked to perform a prospective memory task which includes one of the following three conditions: a reward (i.e., a candy bar), no feedback, or a social motive (i.e., that performing the prospective memory task would be a favor for the experimenter). The participants also rated their commitment to achieve the three prospective conditions. Results showed lower prospective memory in CIND than in controls. Unlike controls, CIND did not benefit from the social motive; however, both populations demonstrated commitment toward this condition relative to the "reward" or "control" conditions. Although social motivation did not ameliorate prospective memory, CIND seem to demonstrate commitment to perform prospective memory tasks that involve social benefits for others.

Effects of Neurocognitive Temporal Training on Weapon Firing Performance

While marksmanship is a critical skill for military personnel, some service members experience difficulty in attaining and maintaining marksmanship qualifications. Temporal training may improve marksmanship performance, since rhythm and timing are critical for coordinated movement. In this study, we examined the effect of neurocognitive temporal training (NTT) on military personnel's marksmanship performance. We randomly assigned 41 active duty U.S. Army service members with prior marksmanship training into an NTT group that received 12 NTT training sessions (N = 18) and a Control group (N = 23) that received no NTT training. We measured marksmanship at baseline (pretest) and following either NTT (posttest) or, for the Control group, a comparable time period. We quantified marksmanship during 2 tasks of firing 5 self-paced shots at stationary 175 m and 300 m targets (Task 1) and firing at 50 moving and stationary targets of varying distances (Task 2). We recorded three measures of accuracy and three measures of precision (including Total Path Length, a unique measure quantifying shot-to-shot variability) for the first task, and we recorded one accuracy measure for the second task. To determine group differences for pretest versus posttest, we used multivariate analysis of variances for Task 1 and a mixed-model analysis of variance for Task 2. Results revealed significantly reduced variability and improved precision when firing at the 175 m target for the NTT group compared with the Control group (p < .05), but there were no significant group differences on other measures. While these results suggest the utility of neurocognitive timing and rhythm training for marksmanship precision, additional research is needed and should include varied training regimens, comparisons of expert versus novice shooters, additional outcome measures, and a larger participant sample.

Medication management abilities are reduced in older persons living with HIV compared with healthy older HIV- controls

Although combination antiretroviral therapy (cART) has simplified over the past decade, polypharmacy is increasing for older people living with HIV (PLWH) due to the emergence of multiple health comorbidities. This study examined predictors of, and relationships between, objective (Medication Management Test-Revised (MMT-R)) and self-reported medication management ability in older (≥ 50 years) PLWH (n = 146) compared with HIV-uninfected (HIV-) individuals (n = 60). PLWH scored worse on the MMT-R and had a higher pill burden compared with HIV- individuals. MMT-R failure was predicted by HIV status, race, reading level, and worse executive functioning, as well as history of Hepatitis C and detectable viral load in PLWH. Self-reported ability to manage medications did not relate to MMT-R score. Older PLWH may not self-describe concerns regarding their ability to manage complex medication regimens. Our results emphasize the need for objective measurements of medication management ability.

Prospective memory and working memory in comparison. New experimental paradigms

Aim of the study: Prospective memory (PM) is a cognitive high load activity. Two main models showed the relation between working memory (WM) and PM. The preparatory attentional and memory processes model (PAM) posits an interdependence between WM and PM; while, the multiprocess framework assumes independence between these two functions.Materials and methods: With the aim to investigate this relation, two tasks were administered to a sample of 21 healthy participants. The first task (arithmetic) required low cognitive and WM load together with a prospective task, the second (PASAT) required high cognitive and WM load together with a prospective switching task. The prospective task included two modalities of administration: based on a sound cue (event-based) or at a given moment (time-based).Results: PM accuracy was influenced by WM only when paired to complex tasks that require high cognitive load on WM and active PM self-retrieval processes (time-PASAT).Conclusions: These results support partial independence between these two mechanisms.

Illegal drug use and prospective memory: A systematic review

Illegal drug use is proposed to interfere with neurobiological functioning by damaging the neurotransmitter communication systems that are believed to be responsible for cognitive abilities, including perception, attention, and memory. This review specifically examined effects of illegal drug use on prospective memory (PM) - memory for future actions. Twenty- seven studies spanning 14 years were included in this review which were divided into two broad categories based on testing methods used: self-report and lab-based testing methods. The quality of the included studies was assessed across five categories: sample type, sample size, abstinence period, testing methods and control for confounding factors. The overall quality of evidence was good for six studies and moderate for sixteen studies and low for five studies. The results from the studies employing self-report were inconsistent as illegal drug users exhibited PM deficits in some studies, but not in others. However, the studies with lab-based testing methods demonstrated more consistent findings with illegal drug users scoring worse than non-users on various PM tests. There were also consistent findings on the link between the dosage of drug taken and level of PM deficit. Based on the literature, there is moderate evidence that illegal drug use impairs PM ability. We recommend that further lab-based studies be conducted to assess dose-response effects on drug-specificity.

Everyday memory problems in alcohol abuse and dependence: Frequency, patterns and patient-proxy agreement

Using self-report to assess everyday memory in alcoholics presents challenges given the presence of both memory and metamemory deficits. Accordingly, evaluation of the reliability and validity of proxy ratings as well as the frequency of these memory lapses are of clinical importance. In the present study, 180 patient-proxy dyads completed the Prospective and Retrospective Memory Questionnaire (PRMQ). 31.7% of proxy-rated versus 2.8% of patient-rated prospective memory scores fell in the impaired to below average range. 15% of proxy-rated retrospective memory scores were below average, whereas none of the patients reported problems in this regard. Longer delays between intention formation and action yielded better prospective memory performance, while the opposite was true for retrospective memory. Agreement between patients and proxies was generally poor to fair across severity levels and the magnitude of observed differences was large (standardized response mean > 0.8). For all PRMQ items, exact agreement occurred in 45.3% of the cases. Larger patient-proxy discrepancy was associated with older age, less education and greater disease severity. Proxy ratings were internally consistent, significantly correlated with objective memory performance, and were sensitive to differences in overall PRMQ performance between severity groups. Caution should be used in the interpretations of patients' reports.

Negative Prospective Memory in Alzheimer's Disease: "Do Not Perform That Action"

Relatively to "standard" prospective memory, i.e., remembering to perform a future action, little is known about negative prospective memory, i.e., remembering not to perform a future action. This study investigated the latter ability in Alzheimer's disease (AD). AD participants and healthy older adults were asked to click on the keyboard or not to click on it when a cue word was encountered. Results showed more omissions (i.e., forgetting to click the keyboard when the instruction was to do so) in AD participants than in healthy older adults, suggesting a prospective memory deficit. Interestingly, more commissions (i.e., clicking the keyboard when the instruction was not to do so) were also observed in AD participants than in healthy older adults. Similar levels of commissions and omissions were observed in AD participants and in healthy older adults. Also, commissions and omissions were correlated with performance on an inhibition assessment task. Our findings reveal that AD is characterized by not only difficulty in the retrieval of recent information, but also difficulty to inhibit no-longer appropriate stimulus-response associations previously learned, suggesting a specific deficit of negative prospective memory in AD.

Prior Task Experience and Comparable Stimulus Exposure Nullify Focal and Nonfocal Prospective Memory Retrieval Differences

We explored the nature of focal versus nonfocal event-based prospective memory retrieval. In the context of a lexical decision task, people received an intention to respond to a single word (focal) in one condition and to a category label (nonfocal) for the other condition. Participants experienced both conditions, and their order was manipulated. The focal instruction condition was a single word presented multiple times. In Experiment 1, the stimuli in the nonfocal condition were different exemplars from a category, each presented once. In the nonfocal condition retrieval was poorer and reaction times were slower during the ongoing task as compared to the focal condition, replicating prior findings. In Experiment 2, the stimulus in the nonfocal condition was a single category exemplar repeated multiple times. When this single-exemplar nonfocal condition followed in time the single-item focal condition, focal versus nonfocal performance was virtually indistinguishable. These results demonstrate that people can modify their stimulus processing and expectations in event-based prospective memory tasks based on experience with the nature of prospective cues and with the ongoing task.

A Meta-Analysis and Critical Review of Prospective Memory in Autism Spectrum Disorder

Prospective memory (PM) is the ability to remember to carry out a planned intention at an appropriate moment in the future. Research on PM in ASD has produced mixed results. We aimed to establish the extent to which two types of PM (event-based/time-based) are impaired in ASD. In part 1, a meta-analysis of all existing studies indicates a large impairment of time-based, but only a small impairment of event-based PM in ASD. In Part 2, a critical review concludes that time-based PM appears diminished in ASD, in line with the meta-analysis, but that caution should be taken when interpreting event-based PM findings, given potential methodological limitations of several studies. Clinical implications and directions for future research are discussed.

Is binding decline the main source of the ageing effect on prospective memory? A ride in a virtual town

Objective: This study was designed to improve our understanding of prospective memory (PM) changes in ageing, and to identify the cognitive correlates of PM decline, using a virtual environment, to provide a more realistic assessment than traditional laboratory tasks.

Design: Thirty-five young and 29 older individuals exposed to a virtual town were asked to recall three event-based intentions with a strong link between prospective and retrospective components, three event-based intentions with a weak link, and three time-based intentions. They also underwent retrospective episodic memory, executive functions, binding in working memory, processing speed, and time estimation assessments.

Results: Older individuals recalled fewer intentions than young adults. While age-related PM decline affected the recall of both prospective and retrospective components, the recall of the latter seemed more challenging for older individuals when the link was weak. This PM decline was linked to an age-related decline in the binding process in working memory, as well as in processing speed, executive functioning, and episodic memory, depending on the nature of intentions.

Conclusion: PM appears to be sensitive to ageing, even when the device is thought to be ecological. This decline is particularly pronounced when controlled processes are needed.

Executive control and working memory are involved in sub-second repetitive motor timing

The nature of the relationship between timing and cognition remains poorly understood. Cognitive control is known to be involved in discrete timing tasks involving durations above 1 s, but has not yet been demonstrated for repetitive motor timing below 1 s. We examined the latter in two continuation tapping experiments, by varying the cognitive load in a concurrent task. In Experiment 1, participants repeated a fixed three finger sequence (low executive load) or a pseudorandom sequence (high load) with either 524-, 733-, 1024- or 1431-ms inter-onset intervals (IOIs). High load increased timing variability for 524 and 733-ms IOIs but not for the longer IOIs. Experiment 2 attempted to replicate this finding for a concurrent memory task. Participants retained three letters (low working memory load) or seven letters (high load) while producing intervals (524- and 733-ms IOIs) with a drum stick. High load increased timing variability for both IOIs. Taken together, the experiments demonstrate that cognitive control processes influence sub-second repetitive motor timing.

Do Baseline Executive Functions Mediate Prospective Memory Performance under a Moderate Dose of Alcohol?

Prospective memory (PM) is memory for delayed intentions. While deleterious effects of acute doses of alcohol on PM have been documented previously using between-subjects comparisons, the current study adopted a single blind placebo-controlled within-subjects design to explore whether the extent to which alcohol-related impairments in PM are mediated by executive functions (EFs). To this end, 52 male social drinkers with no history of substance-related treatment were tested using two parallel versions of a clinical measure of PM (the Memory for Intentions Test; Raskin et al., 2010), and a battery of EF measures. Testing took place on two occasions, with the order of administration of the alcohol and placebo conditions being fully counterbalanced. Overall, PM was worse under alcohol and participants showed deficits on five of the six subscales making up the clinical test. Hierarchical multiple regression analyses demonstrated that EFs did not predict PM performance decrements overall but did predict performance when time cues were presented and when verbal responses were required. Phonemic fluency was the strongest of the EF predictors; a greater capacity to gain controlled access to information in long-term memory predicted a smaller difference between placebo- and alcohol-related performance on both the time cue and verbal response scales. PM is crucial to compliance with, and response to, both therapy programs and alcohol harm prevention campaigns. The results indicate that individual differences in cognitive function need to be taken into account when designing such interventions in order to increase their effectiveness.

Self-Reports of Increased Prospective and Retrospective Memory Problems in Adults with Developmental Dyslexia

Short-term and working memory problems in dyslexia are well-documented, but other memory domains have received little empirical scrutiny, despite some evidence to suggest that they might be impaired. Prospective memory is memory for delayed intentions, whilst retrospective memory relates to memory for personally experienced past events. To gain an understanding of subjective everyday memory experience, a self-report measure designed to tap prospective and retrospective memory was administered to 28 adults with dyslexia and 26 IQ-matched adults without dyslexia. Adults with dyslexia reported experiencing significantly more frequent problems with memory than the adults without dyslexia. Group differences were found across seven out of the eight questionnaire scales. Further to these analyses, the participants' own ratings were compared with proxy ratings provided by close associates. The perception of poorer memory abilities in the participants did not differ between respondent types. The self-reported difficulties are, thus, unlikely to be the result of lowered self-esteem or metacognitive awareness. More frequent difficulties with both types of memory would seem, therefore, to be experienced by adults with dyslexia in everyday life. Further laboratory-based research is recommended to explore both memory domains in dyslexia and to identify the cognitive mechanisms by which these problems occur. Copyright © 2016 John Wiley & Sons, Ltd.

Delayed match-to-sample in working memory: A BrainMap meta-analysis

Working memory (WM), or the ability to temporarily store and manipulate information, is one of the most widely studied constructs in cognitive psychology. Since its inception, it has become one of the leading explanations for how humans are able to operate on a cognitive level. The current study probed the neural networks underlying one of the most commonly used tasks, delayed match-to-sample (DMTS), to study WM. An activation likelihood estimation (ALE) analysis of 42 functional neuroimaging studies (626 participants) was conducted to demonstrate neural network engagement during DMTS. Results demonstrated strong convergence in brain regions commonly associated with the working memory construct (i.e., dorsolateral prefrontal cortex, fusiform gyrus, and posterior parietal cortex). However, neural activation in two regions frequently attributed to WM were absent from this meta-analysis: the anterior cingulate and the rostral prefrontal cortex, suggesting that these regions may be more sensitive to task or stimuli characteristics. In a post-hoc analysis, we deconstructed the DMTS meta-analysis to examine nonverbal versus verbal stimuli, and found notable neurofunctional differences such that DMTS using nonverbal stimuli consistently engaged the right middle frontal gyrus (BA 6/46) and precuneus (BA 7) more so than verbal stimuli based DMTS. These results provide a foundation for future models of functional connectivity that may elucidate subtle differences in working memory attributable to pathological processes.

Prospective Memory

An interesting challenge for researchers who study prospective memory is to explain how people recognize environmental events as cues for actions. Whereas some theorists propose that a capacity-consuming monitoring process is the only means by which intentions can be retrieved, we argue that the cognitive system relies on multiple processes, including spontaneous processes that reflexively respond to the presence of target events. We present evidence for the existence of spontaneous retrieval processes and apply the idea of multiple processes to mixed findings on age-related decline in prospective memory.

The Psychological Lives of the Poor

All individuals rely on a fundamental set of mental capacities and functions, or bandwidth, in their economic and non-economic lives. Yet, many factors associated with poverty, such as malnutrition, alcohol consumption, or sleep deprivation, may tax this capacity. Previous research has demonstrated that such taxes often significantly alter judgments, preferences, and decision-making. A more suggestive but growing body of evidence points toward potential effects on productivity and utility. Considering the lives of the poor through the lens of bandwidth may improve our understanding of potential causes and consequences of poverty.

When Distraction Holds Relevance: A Prospective Memory Benefit for Older Adults

Evidence is accumulating to show that age-related increases in susceptibility to distracting information can benefit older more than young adults in several cognitive tasks. Here we focus on prospective memory (i.e., remembering to carry out future intentions) and examine the effect of presenting distracting information that is intention-related as a function of age. Young and older adults performed an ongoing 1-back working memory task to a rapid stream of pictures superimposed with to-be-ignored letter strings. Participants were additionally instructed to respond to target pictures (namely, animals) and, for half of the participants, some strings prior to the targets were intention-related words (i.e., animals). Results showed that presenting intention-related distracting information during the ongoing task was particularly advantageous for target detection in older compared to young adults. Moreover, a prospective memory benefit was observed even for older adults who showed no explicit memory for the target distracter words. We speculate that intention-related distracter information enhanced the accessibility of the prospective memory task and suggest that when distracting information holds relevance to intentions it can serve a compensatory role in prospective remembering in older adults.

Loads and loads and loads: the influence of prospective load, retrospective load, and ongoing task load in prospective memory

In prospective memory tasks different kinds of load can occur. Adding a prospective memory task can impose a load on ongoing task performance. Adding ongoing task load (OTL) can affect prospective memory performance. The existence of multiple target events increases prospective load (PL) and adding complexity to the to-be-remembered action increases retrospective load (RL). In two experiments, we systematically examined the effects of these different types of load on prospective memory performance. Results showed an effect of PL on costs in the ongoing task for categorical targets (Experiment 2), but not for specific targets (Experiment 1). RL and OTL both affected remembering the retrospective component of the prospective memory task. We suggest that PL can enhance costs in the ongoing task due to additional monitoring requirements. RL and OTL seem to impact the division of resources between the ongoing task and retrieval of the retrospective component, which may affect disengagement from the ongoing task. In general, the results demonstrate that the different types of load affect prospective memory differentially.

Prospective memory: effects of divided attention on spontaneous retrieval

We examined the effects of divided attention on the spontaneous retrieval of a prospective memory intention. Participants performed an ongoing lexical decision task with an embedded prospective memory demand, and also performed a divided-attention task during some segments of lexical decision trials. In all experiments, monitoring was highly discouraged, and we observed no evidence that participants engaged monitoring processes. In Experiment 1, performing a moderately demanding divided-attention task (a digit detection task) did not affect prospective memory performance. In Experiment 2, performing a more challenging divided-attention task (random number generation) impaired prospective memory. Experiment 3 showed that this impairment was eliminated when the prospective memory cue was perceptually salient. Taken together, the results indicate that spontaneous retrieval is not automatic and that challenging divided-attention tasks interfere with spontaneous retrieval and not with the execution of a retrieved intention.

Validation of the Cambridge Prospective Memory Test (Hong Kong Chinese version) for people with stroke

This study aimed to develop and evaluate a Hong Kong Chinese version of the Cambridge Prospective Memory Test (CAMPROMPT-HKCV). Thirty-three subjects at least one year post-stroke participated in the study. They were simultaneously rated on version A of the CAMPROMPT-HKCV by two testers to establish its internal consistency and inter-rater reliability. Raters used the parallel versions of the test (A and B), in rating 10 patients within 2 weeks to establish the parallel form reliability. Another 10 were also assessed on the same day using both version A of the CAMPROMPT-HKCV and the Rivermead Behavioural Memory Test-Chinese version (RBMT-CV) to establish concurrent validity. A new group of 40 stroke patients and 44 healthy controls was recruited to establish its sensitivity and specificity. Results indicated that test-retest reliability on time-based, event-based and total scores, and inter-rater reliability for versions A and B of the test were high. Cronbach's alpha of the event-based score was higher than that of the time-based score. The reliability and concurrent validity of the parallel forms were established. There was a significant difference in performance on CAMPROMPT-HKCV (version A) between the stroke group and the healthy control group. ROC analysis showed that the ability of the cut-off CAMPROMPT-HKCV (total score) to differentiate PM problems was 20.5 (out of 36) with sensitivity at 95.5% and specificity at 55.9%. Further study in developing stratified norms across different age groups in Chinese-speaking stroke patients is recommended.

An investigation into prospective memory in children with developmental dyslexia

Developmental dyslexia hinders reading and writing acquisition of around 5–10% of the children all over the world. However, little is known about role of prospective memory among dyslexics. Prospective memory is realization of delayed intention. Realization of delayed intention requires self initiated process. The present study explored the role of memory (prospective and retrospective memory), meta-memory and attention among dyslexic's children. One hundred and fifteen children (51 dyslexics and 64 normal controls) participated in the study. Prospective and retrospective memory questionnaire, everyday attention questionnaire and meta-memory were administered on children. Analysis of variance was used to analyses the data. All the main effects were significant. Some interactions were also found to be significant. Results suggest that dyslexic's performance on memory (prospective and retrospective memory) was worse than normal control. Meta-memory influences both dyslexics and normal control on prospective and retrospective memory. However, meta-memory affected dyslexics much more than normal control group. Similarly, significant differential effects were observed for simple, difficult and mixed attentional condition among between dyslexics and normal control. Dyslexic's performance was deteriorated as compared to normal control group. The findings of the study are discussed in the light of the existing literature.

Prospective memory: a comparative perspective

Prospective memory consists of forming a representation of a future action, temporarily storing that representation in memory, and retrieving it at a future time point. Here, we review the recent development of animal models of prospective memory. We review experiments using rats that focus on the development of time-based and event-based prospective memory. Next, we review a number of prospective-memory approaches that have been used with a variety of non-human primates. Finally, we review selected approaches from the human literature on prospective memory to identify targets for development of animal models of prospective memory. This article is part of a Special Issue entitled: "Tribute to Tom Zentall".

How important is importance for prospective memory? A review

Forgetting to carry out an intention as planned can have serious consequences in everyday life. People sometimes even forget intentions that they consider as very important. Here, we review the literature on the impact of importance on prospective memory performance. We highlight different methods used to manipulate the importance of a prospective memory task such as providing rewards, importance relative to other ongoing activities, absolute importance, and providing social motives. Moreover, we address the relationship between importance and other factors known to affect prospective memory and ongoing task performance such as type of prospective memory task (time-, event-, or activity-based), cognitive loads, and processing overlaps. Finally, we provide a connection to motivation, we summarize the effects of task importance and we identify important venues for future research.

Functional correlates of prospective memory in stroke

INTRODUCTION

Prospective memory is the ability to remember actions to be performed later in time or when a certain event occurs. Multiple cognitive processes are involved in prospective memory, and the degree to which automatic or effortful processes are involved may differ for different types of prospective memory tasks. This study aimed to investigate prospective memory (dys)functioning in stroke patients, and to get more insight in which cognitive processes are involved in time- versus event-based prospective memory.

METHODS

We investigated 39 community-dwelling stroke survivors and 53 matched control participants. Assessment included naturalistic and experimental event- and time-based prospective memory tasks, as well as standard neuropsychological measures of (retrospective) memory, processing speed and attention/executive functioning.

RESULTS

41% of the stroke patients performed significantly worse than control participants on prospective memory tasks. Deficits in prospective memory occurred as frequently as impairments in retrospective memory (33%, χ(2)(1, N=39)=3.4, p=.066), and more often than impairments in attention/executive functioning (15%, χ(2)(1, N=39)=5.2, p=.022) and speed of processing (23%, χ(2)(1, N=39)=6.5, p=.011). Regression analyses showed that event-based ('focal') prospective memory is supported by retrospective memory, indicating that it is a relatively simple and automatic process. Time-based (non-'focal') prospective memory proved to be a more complex process, requiring active monitoring of the environment. Performance was predicted by speed of processing, attention/executive functioning and retrospective memory. Thirteen percent of the patients suffered from selective prospective memory impairment, which was associated with damage to the superior temporal gyrus.

CONCLUSIONS

Impairment of prospective memory occurs frequently after stroke. Different cognitive operations are involved in distinct types of prospective memory. Results fit within the multi-process framework of prospective memory and help further specify its contents.

Discrepancy-plus-search processes in prospective memory retrieval

In the present study, we investigated the processes underlying prospective memory (PM) retrieval, focusing specifically on two possible spontaneous processes: discrepancy-plus-search and familiarity. Discrepancy was elicited by orthogonally manipulating the processing difficulties of the PM targets and the nontargets. Participants performed a PM task while solving anagrams with two levels of difficulty (easy or difficult). Assuming that the ease of processing easy anagrams would heighten a sense of familiarity, the familiarity view predicted better PM performance with easy anagrams as the PM targets. In contrast, the discrepancy-plus-search view predicted higher PM performance for the PM targets that were anagrams whose difficulty level mismatched that of the surrounding nontargets, as compared to PM targets whose difficulty matched that of the surrounding nontargets. This prediction was based on the idea that mismatching rather than matching difficulty levels would create discrepancy, thereby signaling significance for the target. Participants were more likely to perform the PM task for PM targets that were discrepant, supporting the discrepancy-plus-search view.

Good ergonomics and team diversity reduce absenteeism and errors in car manufacturing

Prior research suggests that ergonomics work design and mixed teams (in age and gender) may compensate declines in certain abilities of ageing employees. This study investigates simultaneous effects of both team level factors on absenteeism and performance (error rates) over one year in a sample of 56 car assembly teams (N = 623). Results show that age was related to prolonged absenteeism and more mistakes in work planning, but not to overall performance. In comparison, high-physical workload was strongly associated with longer absenteeism and increased error rates. Furthermore, controlling for physical workload, age diversity was related to shorter absenteeism, and the presence of females in the team was associated with shorter absenteeism and better performance. In summary, this study suggests that both ergonomics work design and mixed team composition may compensate age-related productivity risks in manufacturing by maintaining the work ability of older employees and improving job quality.

Prospective Memory in Complex Sociotechnical Systems

An important cognitive function is the ability to remember to execute future tasks, a capability known as prospective memory (PM). Workers in complex sociotechnical systems such as healthcare and aviation face many PM challenges and forgetting tasks can have severe consequences. Although researchers have made progress in understanding how individuals remember future tasks, system-level support for PM has seldom been addressed. In the present paper, we briefly review PM research in healthcare and aviation, focusing on naturalistic studies using expert workers, and we present the concept of distributed prospective memory, which incorporates the interaction between the environment and the individual when future tasks must be remembered. PM in sociotechnical settings is a complex process involving human and nonhuman agents. Therefore, a systems approach is needed to fully understand PM processes, thus supporting workers and eventually minimizing errors and increasing safety.

Individual Differences in the Delayed Execution of Prospective Memories

Working memory processes play a critical role in actively maintaining, rehearsing, and retrieving goal-relevant information during cognitively engaging tasks. In the current study, we examined individual differences in prospective memory between young adults with high versus low working memory capacity (WMC) when they had to momentarily delay their intentions for either 6 or 42 s. In Experiments 1 and 2, high-WMC individuals performed significantly better at both delay intervals than did low-WMC individuals under standard ongoing task conditions. In Experiment 2, we included an interrupting task during the longer delay that decreased performance in the low-WMC relative to the high-WMC individuals. These results suggest that prospective memory performance is generally impaired across all retention intervals in low-WMC individuals, and that high-WMC individuals may be better able to retrieve the intention from long-term memory even when attention is interrupted by intervening activities.