A process-model based approach to prospective memory impairment in Parkinson's disease

Neurocognitive functioning of patients with early-stage Parkinson's disease

Parkinson's disease (PD) is a neurological disorder commonly associated with motor deficits. However, cognitive impairment is also common in patients with PD. Cognitive concerns in PD may affect multiple domains of neurocognition and vary across different stages of the disease. Extant research has focused mainly on cognitive deficits in middle to late stages of PD, whereas few studies have examined the unique cognitive profiles of patients with early-stage PD. This study addressed this gap in the published literature and examined neurocognitive functioning and functional capacity of patients with de novo PD, focusing on the unique pattern of cognitive deficits specific to the early stage of the disease. Results indicated that the pattern of cognitive deficits in patients with PD (n = 55; mean age = 72.93) was significantly different from healthy controls (n = 59; mean age = 71.88). Specifically, tasks related to executive functioning, attention, and verbal memory demonstrated the most pronounced deficits in patients with early-stage PD. Clinical implications of these findings are discussed.

From the lab to the classroom: Improving children's prospective memory in a natural setting

BACKGROUND

Laboratory-based studies have shown that children's ability to remember intentions (i.e., prospective memory; PM) can be improved by asking them to imagine performing the PM task beforehand (i.e., episodic future thinking; EFT) or to predict their PM performance. Moreover, combining the two strategies resulted in an additional improvement in children's PM performance. However, the effectiveness of these encoding strategies on real-life PM tasks is still unknown.

AIMS

The aim of the present study was to evaluate the effect of EFT instructions, performance predictions, and of their combination on children's PM in a natural setting, namely in the classroom.

SAMPLE

Twelve classes composed by a total of 121 children (53% females) aged between seven and 9 years participated to the study.

METHODS

As a PM task, children were asked by their teachers to deliver a letter to their parents and to bring it back to school the next day. Children were divided into four groups: control, prediction, EFT, and the EFT + prediction group. Parent reports on children's everyday prospective and retrospective memory failures were also collected.

RESULTS

Results showed that encoding strategies were effective in enhancing children's PM performance. However, differences compared to previous laboratory-based findings emerged since predicting PM performance resulted to be most effective in enhancing real-life PM performance. Moreover, parent reports were related to children's PM performance.

CONCLUSIONS

These novel findings highlight the importance of studying PM interventions in natural settings in order to increase their ecological validity and inform educational practices.

Further clarification of cognitive processes of prospective memory in schizophrenia by comparing eye-tracking and ecologically-valid measurements

The aim of this study is to compare ecologically-valid measure (the Cambridge Prospective Memory Test, CAMPROMPT) and laboratory measure (eye-tracking paradigm) in assessing prospective memory (PM) in individuals with schizophrenia spectrum disorders (SSDs). In addition, eye-tracking indices are used to examine the relationship between PM and other cognitive domains in SSDs patients. Initially, the study sample was formed by 32 SSDs patients and 32 healthy control subjects (HCs) who were matched in sociodemographic profile and the performance on CAMPROMPT. An eye-tracking paradigm was employed to examine the differences in PM accuracy and key cognitive processes (e.g., cue monitoring) between the two groups. Additional 31 patients were then recruited to investigate the relationship between PM cue monitoring, other cognitive functions, and the severity of clinical symptoms within the SSDs group. The monitoring of PM cue was reflected in total fixation time and total fixation counts for distractor words. Cognitive functions were assessed using the Chinese version of the MATRICS Consensus Cognitive Battery (MCCB). The Positive and Negative Syndrome Scale (PANSS) was applied to assess psychopathology. SSDs patients exhibited fewer total fixation counts for distractor words and lower PM accuracy compared to HCs, even though they were priori matched on CAMPROMPT. Correlation analysis within the SSDs group (63 cases) indicated a negative correlation between PM accuracy and PANSS total score, and a positive correlation with working memory and attention/vigilance. Regression analysis within the SSDs group revealed that higher visual learning and lower PANSS total scores independently predicted more total fixation counts on distractor words. Impairment in cue monitoring is a critical factor in the PM deficits in SSDs. The eye-tracking laboratory paradigm has advantages over the ecologically-valid measurement in identifying the failure of cue detection, making it a more sensitive tool for PM deficits in patients with SSDs.

Improving children's ability to remember intentions: a literature review on strategies to improve prospective memory during childhood

Children often fail to remember executing intentions because prospective memory (PM) does not completely develop until late adolescence or young adulthood. PM failures are often observed in children and can have negative consequences on their everyday lives. Thus, in the last 50 years, various strategies to support children's PM have been designed and evaluated, such as prompting children to use different encoding modalities, such as verbal, visual, and enacted modalities, or encoding strategies, such as implementation intentions, episodic future thinking (EFT), and performance predictions, as well as providing children with verbal and visual reminders. However, not all these interventions have shown to efficiently enhance PM performance during childhood. The present literature review is aimed at summarizing these interventions and critically examining their effectiveness from a developmental perspective and by considering underlying mechanisms. The type of PM task (event-, time-, and activity-based), cognitive resource demands, and processing overlaps are also considered. Finally, directions for future research and possible applications in everyday life will be discussed.

The effectiveness of an immersive virtual reality and telemedicine-based cognitive intervention on prospective memory in Parkinson's disease patients with mild cognitive impairment and healthy aged individuals: design and preliminary baseline results of a placebo-controlled study

Introduction

Prospective memory (PM) impairments have been extensively documented in individuals with Parkinson's disease associated with mild cognitive impairment (PD-MCI) and in those with healthy aging. Considering how PM failure decreases individuals' quality of life and functional independence in the activities of daily living, training to enhance this ability could be a prior target of intervention.

Objective

Here, we aimed to present the study protocol and preliminary results of a novel immersive virtual reality (IVR) and telemedicine-based (TM) cognitive intervention focused on executive abilities (i.e., planning, shifting, and updating) to improve PM functioning in PD-MCI patients and healthy elderly individuals.

Methods

Outcome measures, collected before, immediately after and 2 months after the intervention, included: (1) pre-post training changes in objective cognitive functioning, evaluated with tests assessing executive functions and PM; (2) pre-post training changes in subjective perception of memory functioning, psychiatric symptoms, autonomy in daily living and quality of life, evaluated using the appropriate scales; (3) usability, feasibility and users' compliance with the proposed IVR and telemedicine program. The efficacy of this intervention compared to an active control condition is currently being evaluated in a randomized, double-blind controlled trial, which will be conducted on 30 eligible PD-MCI patients and 30 older adults.

Results

Preliminary results concerning between-group comparisons of demographic and neuropsychological screening data show a good balance among the intervention groups considered in this study. The results also suggest good levels of usability, feasibility and acceptability, thus supporting the notion that our intervention can be used to promote cognitive functioning, even in people with cognitive decline.

Conclusion

Considering the relatively low costs and easy accessibility to this program, it could prove valuable in primary prevention initiatives and early cognitive rehabilitation for dementia risk reduction.

Associations between intraindividual reaction time variability and prospective memory performance in patients with schizophrenia and healthy controls

Introduction: Patients with schizophrenia exhibit prospective memory (PM) impairment. Intraindividual reaction time variability (IIRTV) is an index of attentional control that is required for PM. This study examined the differences in IIRTV between patients with schizophrenia and healthy controls and the relationship between IIRTV and PM performance.Method: Thirty-nine patients with schizophrenia and forty-two healthy controls were recruited to complete a PM task and the Sustained Attention to Response Task. IIRTV was calculated as the coefficient of variation (mean/SD) of reaction time over correctly responded trials in these tasks.Results: Patients with schizophrenia showed lower PM accuracy and increased IIRTV, while the associations between PM accuracy and IIRTV were significant in healthy controls but not in patients with schizophrenia.Conclusion: These findings suggest impaired PM and relationship between PM and attentional control in patients with schizophrenia.

Transferability and sustainability of process-based multi-task adaptive cognitive training in community-dwelling older adults with mild cognitive impairment: a randomized controlled trial

BACKGROUND

Cognitive training shows promising effects for improving cognitive domains in individuals with mild cognitive impairment (MCI), including the crucial predictive factor of executive function (EF) for dementia prognosis. Few studies have paid sufficient emphasis on the training-induced effects of cognitive training programs, particularly with regards to targeting EF. A process-based multi-task adaptive cognitive training (P-bM-tACT) program targeting EF is required to examine direct, transfer, and sustainability effects in older adults with MCI.

OBJECTIVE

This study aimed to evaluate the direct effects of a P-bM-tACT program on EF, the transfer effects on untrained cognitive domains, and further explore the sustainability of training gains for older adults with MCI in the community.

METHODS

In a single-blind, randomized controlled trial, 92 participants with MCI were randomly assigned to either the intervention group, participating in a P-bM-tACT program (3 training sessions/week, 60 min/session for 10 weeks) or the wait-list control group, accepting a health education program on MCI (1 education session/ twice a week, 40-60 min/session for 10 weeks). The direct and transfer effects of the P-bM-tACT program were assessed at baseline, immediately after 10 weeks of training, and the 3-month follow-up. Repeated measures analysis of variance and a simple effect test were used to compare the direct and transfer effects over the 3-time points between the two groups.

RESULTS

The P-bM-tACT program yielded a greater benefit of direct and transfer effects in the intervention group participants than in the wait-list control group. Combined with the results of simple effect tests, the direct and transfer effects of participants in the intervention group significantly increased immediately after 10 weeks of training compared to the baseline (F = 14.702 ~ 62.905, p < 0.05), and these effects were maintained at the 3-month follow-up (F = 19.595 ~ 122.22, p < 0.05). Besides, the acceptability of the cognitive training program was established with a high adherence rate of 83.4%.

CONCLUSIONS

The P-bM-tACT program exerted positive direct and transfer effects on the improvement of cognitive function, and these effects were sustained for 3 months. The findings provided a viable and potential approach to improving cognitive function in older adults with MCI in the community.

TRIAL REGISTRATION

The trial was registered at Chinese Clinical Trials Registry on 09/01/2019 ( www.chictr.org.cn ; Number Registry: ChiCTR1900020585).

The deficient cue monitoring and the facilitating effect of prosocial intention on prospective memory in patients with schizophrenia spectrum disorders

The study aimed to investigate the cognitive processing of prospective memory (PM) in patients with schizophrenia spectrum disorders (SSDs) by using an eye-tracking paradigm. In addition, the facilitating effects of prosocial intention (the desire to help others) on PM in SSDs were also examined. In phase 1, 26 patients (group1) and 25 healthy controls (HCs) were compared in an eye-tracking PM paradigm in terms of the PM accuracy and eye-tracking indices. In phase 2, 21 more patients (group2) were recruited, and a prosocial intention was introduced in the eye-tracking PM paradigm. Their PM accuracy and eye-tracking indices were compared with those in group1. The PM cue monitoring was indicated by the total fixation counts and fixation time on distractor words. In phase 1, group1 showed lower PM accuracy, fewer fixation counts and less fixation time on distractor words than HCs. In phase 2, group2 (with prosocial intention) performed significantly better than group1 (with typical instruction) on both PM accuracy and fixation time on distractor words. In both groups of SSDs, the PM accuracy was significantly correlated with both the fixation counts and the fixation time of distractor words. After controlling for the cue monitoring indices, the difference in PM accuracy remained significant between group1 and HCs but disappeared between group1 and group2. The cue monitoring deficit contributes to the PM impairment in SSDs. The facilitating effect of prosocial intention disappears after the control of cue monitoring, also indicating its critical role in PM.

Assessment of goal-directed behavior with the 3D videogame EPELI: Psychometric features in a web-based adult sample

EPELI (Executive Performance in Everyday LIving) is a recently developed gaming tool for objective assessment of goal-directed behavior and prospective memory (PM) in everyday contexts. This pre-registered study examined psychometric features of a new EPELI adult online version, modified from the original child version and further developed for self-administered web-based testing at home. A sample of 255 healthy adults completed EPELI where their task was to perform household chores instructed by a virtual character. The participants also filled out PM-related questionnaires and a diary and performed two conventional PM tasks and an intelligence test. We expected that the more "life-like" EPELI task would show stronger associations with conventional PM questionnaires and diary-based everyday PM reports than traditional PM tasks would do. This hypothesis did not receive support. Although EPELI was rated as more similar to everyday tasks, performance in it was not associated with the questionnaires and the diary. However, there were associations between time-monitoring behavior in EPELI and the traditional PM tasks. Taken together, online adult-EPELI was found to be a reliable method with high ecological face validity, but its convergent validity requires further research.

Do executive functions explain older adults' health-related quality of life beyond event-based prospective memory?

Previous work has shown that event-based prospective memory (EBPM) predicted health-related quality of life (HrQoL). In the present study, we aimed to examine whether the relationship between EBPM and HrQoL extended to life satisfaction, and whether it persisted after controlling for other cognitive functions related to EBPM, namely executive functions and retrospective memory. We tested two models using structural equation modeling with latent variables in a sample of older adults. In the first model, we assessed whether EBPM predicted life satisfaction and HrQoL; in the second model, we controlled for retrospective memory and executive functions. The first model indicated that EBPM was related to HrQoL. However, in the second model, this relationship was eliminated by executive functions; life satisfaction was not related to any of the cognitive variables. Findings corroborated the link between HrQoL and EBPM, suggesting that such relationship stems from executive functions rather than retrospective memory.

Do emotionally salient cues improve prospective memory performance in children and adolescents with autism?

BACKGROUND

Prospective memory (PM) describes the ability to initiate and perform a planned action after a delay. Previous studies suggest reduced PM in autism spectrum disorder (ASD); especially when tasks put high demands on executive control resources. Increasing cue salience by presenting emotional cues improves PM performance in non-autistic populations.

AIMS

To explore whether children with ASD, whose processing of emotionally connoted information might differ from that of typically developing children, may also benefit from this type of salience in PM tasks.

METHODS AND PROCEDURES

Twenty-five children with and 25 children without ASD completed a 1-back ongoing task into which an event-based PM task was embedded. Emotional salience of PM cues was varied.

OUTCOMES AND RESULTS

Children with ASD performed as well as children without ASD on the PM task and equally benefited from emotionally salient cues. Specifically, negative cues increased PM performance compared to neutral cues in both groups CONCLUSIONS AND IMPLICATIONS: The findings are consistent with the multiprocess framework which postulates that salient PM cues increase performance by promoting automatic intention retrieval and reducing executive control demands. Children with ASD seem to show similar comprehension and accessibility to emotional cues as typically developing children.

Event-Related Brain Potential Correlates of Event-Based Prospective Memory in Children With Learning Disability

Prospective memory (PM) has been reported to be impaired in children with learning disabilities (LD), but few studies have examined the underlying neural mechanism of this impairment. To address this issue, the present study applied ERP technique to explore the difference of event-based prospective memory (EBPM) in 21 children with LD and 20 non-LD children with double task paradigm. Results from behavioral data showed that LD children exhibited lower accuracy than non-LD children. The ERP results showed that the two groups displayed significant difference in the ERP components, with longer N300 latency in LD group, but there was no obvious difference found in the prospective positivity component. The present findings seem to indicate that the poor performance of LD children on PM task might be result from deficits in PM cues detection. These results provided evidence for the existence of altered PM processing in LD children, which was characterized by a selective deficit in cues detection of PM. Therefore, these findings shed new light on the neurophysiological processes underlying PM in children with LD.

Prospective Memory Training in Older Adults: A Systematic Review and Meta-Analysis

Prospective memory (PM), which enables one to remember to carry out delayed intentions, is crucial for everyday functioning. PM commonly deteriorates upon cognitive decline in older adults, but several studies have shown that PM in older adults can be improved by training. The current study aimed to summarise this evidence by conducting a qualitative systematic analysis and quantitative meta-analysis of the effects of PM training in older adults, for which systematic searches were conducted across seven databases (Cochrane Library, Embase, PubMed, PsycInfo, Web of Science, CINAHL and Scopus). Forty-eight studies were included in the qualitative analysis, and 43% of the assessed PM training interventions showed positive gains in enhancing PM. However, the methodological quality varied across the studies, with 41% of the non-randomised control trials (non-RCTs) rated as having either serious or critical risk of bias. Therefore, only 29 RCTs were included in the subsequent quantitative meta-analysis. We found a significant and moderate immediate efficacy (Hedges' g = 0.54) of PM training in enhancing PM performance in older adults, but no significant long-term efficacy (Hedges' g = 0.21). Two subgroup analyses also revealed a robust training efficacy across the study population (i.e., healthy and clinical population) and the number of training sessions (i.e., single session and programme-based). Overall, this study provided positive evidence to support PM training in older adults. Further studies are warranted to explore the mechanisms by which PM training exerts its effects, and better-quality RCTs are needed to provide more robust evidence supporting our findings.

Prospective Memory Training for Healthy Older Adults: A Systematic Review

OBJECTIVES

This review systematically synthesizes existing evidence of prospective memory training for healthy older adults (> 55 years). Existing prospective memory training include strategy-based, process-based and combined regimens. Strategy-based training focuses on different mnemonics to compensate for aging declines in prospective memory. Process-based training aims to restore related cognitive processes to support prospective memory. Combined training utilizes both strategy-based and process-based regimens to enhance prospective memory performance.

METHODS

A total of 349 studies were identified from the Cochrane Library, EBSCO, PsycINFO and PubMed databases.

RESULTS

Using predefined inclusion and exclusion criteria, 11 studies were included in the review. There were six studies of strategy-based training, two studies of process-based training and three studies of combined training.

CONCLUSIONS

Overall, strategy-based training appears to facilitate prospective memory for healthy older adults. However, it is impossible to draw conclusions for process-based and combined training due to the preliminary nature of current evidence.

CLINICAL IMPLICATIONS

Mental imagery or the use of external aids can be useful strategy-based approaches to facilitate prospective memory in older adults. Strategy-based training should target multiple prospective memory phases simultaneously to encourage transfers. Further studies will be required to draw conclusions on the effectiveness of process-based and combined training.

The Chinese version of the Memory for Intentions Test (MIST): development and evaluation of its reliability and concurrent validity

This study aims to develop a simplified Chinese version of the "Memory for Intentions Test" (MIST), evaluate its reliability and concurrent validity, explore the inter-relationships among the MIST variables and the relationships between the MIST variables and socio-demographic factors.

Two hundred healthy, Chinese-speaking adults of the Han community participated in this study. Form A of the Chinese MIST and two prospective items of the Rivermead Behavioural Memory Test, Second Edition (RBMT-II, Chinese version) were administered to all participants to evaluate internal consistency, split-half reliability, and concurrent validity. Twenty of these participants were assessed twice on Form A with a two-week interval to examine test-retest reliability. They were also assessed on both Form A and Form B to examine alternate-form reliability.

The findings of the study indicated good internal consistency (Cronbach's α = .833) and excellent split-half reliability (r = .924-.930) among the six subscales of the Chinese MIST, although the internal consistency was low (Cronbach's α = .129) for individual PM trials. We also found adequate concurrent validity (ρ = .722, p< .001), test-retest reliability (ρ = .716, p < .001), and alternate-form reliability (ρ= .828, p < .001).

The Chinese MIST demonstrated suitable reliability and concurrent validity in the Chinese-speaking population. The present study provides a new standardized prospective memory test for the Chinese population, which would enhance future clinical research in this field on the Chinese mainland.

Patients' Self-Report and Handwriting Performance Features as Indicators for Suspected Mild Cognitive Impairment in Parkinson's Disease

Early identification of mild cognitive impairment (MCI) in Parkinson's disease (PD) patients can lessen emotional and physical complications. In this study, a cognitive functional (CF) feature using cognitive and daily living items of the Unified Parkinson's Disease Rating Scale served to define PD patients as suspected or not for MCI. The study aimed to compare objective handwriting performance measures with the perceived general functional abilities (PGF) of both groups, analyze correlations between handwriting performance measures and PGF for each group, and find out whether participants' general functional abilities, depression levels, and digitized handwriting measures predicted this CF feature. Seventy-eight participants diagnosed with PD by a neurologist (25 suspected for MCI based on the CF feature) completed the PGF as part of the Daily Living Questionnaire and wrote on a digitizer-affixed paper in the Computerized Penmanship Handwriting Evaluation Test. Results indicated significant group differences in PGF scores and handwriting stroke width, and significant medium correlations between PGF score, pen-stroke width, and the CF feature. Regression analyses indicated that PGF scores and mean stroke width accounted for 28% of the CF feature variance above age. Nuances of perceived daily functional abilities validated by objective measures may contribute to the early identification of suspected PD-MCI.

Distinct monitoring strategies underlie costs and performance in prospective memory

Prospective memory (PM) describes the ability to remember to perform goal-relevant actions at an appropriate time in the future amid concurrent demands. A key contributor to PM performance is thought to be the effortful monitoring of the environment for PM-related cues, a process whose existence is typically inferred from a behavioral interference measure of reaction times. This measure, referred to as "PM costs," is an informative but indirect proxy for monitoring, and it may not be sufficient to understand PM behaviors in all situations. In this study, we asked participants to perform a visual search task with arrows that varied in difficulty while concurrently performing a delayed-recognition PM task with pictures of faces and scenes. To gain a precise measurement of monitoring behavior, we used eye-tracking to record fixations to all task-relevant stimuli and related these fixation measures to both PM costs and PM accuracy. We found that PM costs reflected dissociable monitoring strategies: higher costs were associated with early and frequent monitoring while lower costs were associated with delayed and infrequent monitoring. Moreover, the link between fixations and PM costs varied with cognitive load, and the inclusion of fixation data yielded better predictions of PM accuracy than using PM costs alone. This study demonstrates the benefit of eye-tracking to disentangle the nature of PM costs and more precisely describe strategies involved in prospective remembering.

An ecologically valid examination of event-based and time-based prospective memory using immersive virtual reality: The influence of attention, memory, and executive function processes on real-world prospective memory

Studies on prospective memory (PM) predominantly assess either event- or time-based PM by implementing non-ecological laboratory-based tasks. The results deriving from these paradigms have provided findings that are discrepant with ecologically valid research paradigms that converge on the complexity and cognitive demands of everyday tasks. The Virtual Reality Everyday Assessment Lab (VR-EAL), an immersive virtual reality (VR) neuropsychological battery with enhanced ecological validity, was implemented to assess everyday event- and time-based PM, as well as the influence of other cognitive functions on everyday PM functioning. The results demonstrated the role of delayed recognition, planning, and visuospatial attention on everyday PM. Delayed recognition and planning ability were found to be central in event- and time-based PM respectively. In order of importance, delayed recognition, visuospatial attention speed, and planning ability were found to be involved in event-based PM functioning. Comparably, planning, visuospatial attention accuracy, delayed recognition, and multitasking/task-shifting ability were found to be involved in time-based PM functioning. These findings further suggest the importance of ecological validity in the study of PM, which may be achieved using immersive VR paradigms.

The benefits of emotionally salient cues on event-based prospective memory in bipolar patients and schizophrenia patients

Prospective memory (PM) refers to the ability to remember to carry out a delayed intention in the future. Evidence suggests that emotionally salient cues can enhance PM functions in healthy population, but whether the benefit exists in schizophrenia and bipolar patients remains unclear. This study aimed to examine and compare the potential enhancement effect of emotional PM cues in schizophrenia patients and bipolar patients. Twenty-eight clinically stable schizophrenia participants, 26 euthymic bipolar participants and 29 controls completed a computerized PM task involving PM cues with different types of valences (i.e., positive, neutral and negative). All the three groups showed better PM performance when negative PM cues were presented compared with positive and neutral PM cues. The sizes of the enhancement effects of negative PM cues were large (all Cohen's d ≥ 1.00) and comparable across three groups. Our findings suggested that patients with schizophrenia and bipolar disorders could benefit from negative PM cues to an extent similar to healthy individuals, thus extended the notion of psychosis continuum to the important area of emotion-cognition interaction.

Neurophysiological markers of prospective memory and working memory in typical ageing and mild cognitive impairment

OBJECTIVE

Prospective memory (PM) -the memory of delayed intentions- is impacted by age-related cognitive decline. The current event-related potential study investigates neural mechanisms underpinning typical and atypical (Mild Cognitive Impairment, MCI) age-related decline in PM.

METHODS

Young adults (YA, n = 30, age = 24.7, female n = 13), healthy older adults (OA, n = 39, age = 72.87, female n = 24) and older adults with MCI (n = 27, age = 77.54, female n = 12) performed two event-based PM tasks (perceptual, conceptual) superimposed on an ongoing working memory task. Electroencephalographic data was recorded from 128 electrodes. Groups were compared for P2 (higher order perceptual processing), N300/frontal positivity (cue detection), the parietal positivity (retrieval), reorienting negativity (RON; attention shifting).

RESULTS

Participants with MCI had poorer performance (ongoing working memory task, conceptual PM), lower P2 amplitudes, and delayed RON (particularly for perceptual PM) than YA and OA. MCI had lower parietal positivity relative to YA only. YA had earlier latencies for the parietal positivity than MCI and OA, and lower amplitudes for N300 (than OA) and frontal positivity (than OA and MCI).

CONCLUSIONS

Impaired attention and working memory may underpin PM deficits in MCI.

SIGNIFICANCE

This is the first study to document the role of RON in PM and to investigate neurophysiological mechanisms underpinning PM in MCI.

Subjective Time in Dementia: A Critical Review

The capacity for subjective time in humans encompasses the perception of time's unfolding from moment to moment, as well as the ability to traverse larger temporal expanses of past- and future-oriented thought via mental time travel. Disruption in time perception can result in maladaptive outcomes-from the innocuous lapse in timing that leads to a burnt piece of toast, to the grievous miscalculation that produces a traffic accident-while disruption to mental time travel can impact core functions from planning appointments to making long-term decisions. Mounting evidence suggests that disturbances to both time perception and mental time travel are prominent in dementia syndromes. Given that such disruptions can have severe consequences for independent functioning in everyday life, here we aim to provide a comprehensive exposition of subjective timing dysfunction in dementia, with a view to informing the management of such disturbances. We consider the neurocognitive mechanisms underpinning changes to both time perception and mental time travel across different dementia disorders. Moreover, we explicate the functional implications of altered subjective timing by reference to two key and representative adaptive capacities: prospective memory and intertemporal decision-making. Overall, our review sheds light on the transdiagnostic implications of subjective timing disturbances in dementia and highlights the high variability in performance across clinical syndromes and functional domains.

Prospective memory deficits following acute alcohol consumption

BACKGROUND

Prospective memory is a critical neurocognitive capacity that refers to the ability to execute delayed intentions. To date, few studies have investigated the effects of acute alcohol consumption on prospective memory, and important questions remain about the mechanisms that might underpin acute alcohol-induced prospective memory impairment.

AIMS

The current study sought to clarify the nature and magnitude of prospective memory difficulties following acute alcohol consumption and to test the degree to which any problems with prospective remembering might be a secondary consequence of broader cognitive impairment. This study also investigated whether there were potential sex differences.

METHODS

In all, 124 healthy adult social drinkers were assigned to either the alcohol (n = 61) or placebo (n = 63) condition. Participants were administered a dose of 0.6 g/kg alcohol or a matched placebo drink and then asked to complete a measure of prospective memory. A broader neurocognitive test battery was also administered.

RESULTS

Relative to the placebo condition, acute alcohol intoxication led to significant impairment on all prospective memory tasks, with effects mostly large in magnitude. These difficulties could not be explained by broader problems in retrospective memory, executive function or episodic future thinking. In addition, females recorded a higher blood alcohol concentration than males; however, no sex differences in prospective memory performance were identified following acute alcohol use.

CONCLUSION

The results show that acutely, even a moderate dose of alcohol substantially impairs prospective memory function. These findings have potentially important implications for understanding many of the maladaptive behaviours associated with acute alcohol consumption.

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.

Inhibitory control in prospective memory: An event related potential comparison of task-switch and dual task processing

This study cross-validates reported changes in behavioural and event-related potential (ERP) correlates of prospective memory (PM) inhibitory control performance applying different PM response selection demands (Bisiacchi et al., 2009). Participants were randomly assigned to a control group condition with no PM requirement, or to either inhibit ongoing task processing to respond to PM task cues (task-switch; TS) or provide an ongoing task response prior to providing a PM button press (dual-task; DT). The behavioural data indicated that ongoing task reaction time (RT) performance was similar in the DT, TS, and control group conditions. PM cue detection mechanisms reflected by the N300 did not differ between PM tasks. However, early occurring (400-700 ms) PM late parietal complex (LPC) amplitudes recorded over anterior electrode sites were larger in the TS compared to the DT-PM condition, and this difference persisted during the 700-1000 ms epoch. Thus, ERP correlates of PM task-set remapping were significantly altered via the induction of different PM response production rules retrieved from retrospective memory (RM). The enhancement of anteriorly distributed TS LPC amplitudes between 400 and 700 ms led to the suggestion that increased inhibition in this group condition was accompanied by heightened frontally mediated neural activations that support prepotent ongoing task response inhibition processing.

Prospective memory impairment in neurological disorders: implications and management

Prospective memory is a core neurocognitive ability that refers to memory for future intentions, such as remembering to take medications and to switch off appliances. Any breakdown in prospective memory, therefore, has serious implications for the ability to function independently in everyday life. In many neurological disorders, including Parkinson disease and dementia, prospective memory deficits are common even in the earliest stages and typically become more severe with disease progression. Consequently, clinical assessment of prospective memory is of critical importance. This article provides an overview of the various manifestations and neural bases of prospective memory deficits. To facilitate clinical decision-making, validated measures of this construct are identified and their suitability for clinical practice is discussed, focusing in particular on clinical sensitivity and psychometric properties. The article concludes by reviewing the approaches that can be used to rehabilitate different types of prospective memory impairment, and algorithms to guide the evaluation and treatment of these impairments are provided.

Effects of Mental Imagery on Prospective Memory: A Process Analysis in Individuals with Amnestic Mild Cognitive Impairment

INTRODUCTION

Prospective memory (PM) is a multiphasic cognitive function important for autonomy and functional independence but is easily disrupted by pathological aging processes. Through cognitive simulation of perceptual experiences, mental imagery could be an effective compensatory strategy to enhance PM performance. Nevertheless, relevant research in individuals with amnestic mild cognitive impairment (MCI) has been limited, and the underlying mechanism of the therapeutic effect has not been sufficiently elucidated. The present study aimed to examine complex PM performances and the effect of mental imagery on each phase in older adults with MCI and to investigate the underlying cognitive mechanism from a process perspective.

METHODS

Twenty-eight MCI and 32 normal aging controls completed a seminaturalistic PM task, in addition to a series of neuropsychological tests. Participants from each group were randomly assigned to a mental imagery condition or a standard repeated encoding condition before performing the PM task. Four indices were used to measure performance in the intention formation, intention retention, intention initiation, and intention execution phases of PM. Performances in each phase was compared between the 2 diagnostic groups and the 2 instruction conditions.

RESULTS

The MCI group performed worse than the normal aging group in the intention formation and intention retention phases. The participants in the mental imagery condition performed significantly better than those in the standard condition during the intention formation, intention retention, and intention execution phases, regardless of the diagnostic group. Moreover, there was a significant interaction between the group and condition during intention retention, showing that people with MCI benefited even more from mental imagery than normal aging in this phase. Performance in the intention retention phase predicted performance in the intention initiation and intention execution phases.

DISCUSSION

PM deficits in MCI mainly manifest during planning and retaining intentions. Mental imagery was able to promote performance in all but the initiation phase, although a trend for improvement was observed in this phase. The effects of mental imagery may be exerted in the intention retention phase by strengthening the PM cue-action bond, thereby facilitating the probability of intention initiation and bolstering fidelity to the original plan during intention execution.

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.

The Effects of Working Memory Updating Training in Parkinson's Disease: A Feasibility and Single-Subject Study on Cognition, Movement and Functional Brain Response

In Parkinson’s disease (PD), the fronto-striatal network is involved in motor and cognitive symptoms. Working memory (WM) updating training engages this network in healthy populations, as observed by improved cognitive performance and increased striatal BOLD signal. This two-part study aimed to assess the feasibility of WM updating training in PD and measure change in cognition, movement and functional brain response in one individual with PD after WM updating training. A feasibility and single-subject (FL) study were performed in which patients with PD completed computerized WM updating training. The outcome measures were the pre-post changes in criterion and transfer cognitive tests; cognitive complaints; psychological health; movement kinematics; and task-related BOLD signal. Participants in the feasibility study showed improvements on the criterion tests at post-test. FL displayed the largest improvements on the criterion tests and smaller improvements on transfer tests. Furthermore, FL reported improved cognitive performance in everyday life. A shorter onset latency and smoother upper-limb goal-directed movements were measured at post-test, as well as increased activation within the striatum and decreased activation throughout the fronto-parietal WM network. This two-part study demonstrated that WM updating training is feasible to complete for PD patients and that change occurred in FL at post-test in the domains of cognition, movement and functional brain response.

Effect of Process-Based Multi-Task Cognitive Training Program on Executive Function in Older Adults With Mild Cognitive Impairment: Study Rationale and Protocol Design for a Randomized Controlled Trial

INTRODUCTION

Recent research from both human and animal studies confirms that cognitive training gains a considerable effect on multiple cognitive domains in older adults with mild cognitive impairment. Previous studies have yet paid scant attention to executive function training. Little is known about whether this specific benefit translates to maintaining long-term effectiveness and transfer effects are. This study is designed as an effort to address this issue.

OBJECTIVE

The program aimed to evaluate the effect of process-based multi-task cognitive training on executive function and further explore its long-term effects and transfer effects in older adults with MCI. Furthermore, we will explore the neural correlates latent the changed performances underlying the cognitive intervention.

METHODS

This program is a single-blinded, randomized, prospective clinical trial to test the effect of process-based multi-task cognitive training in older adults with MCI. Ninety participants with MCI will be recruited and randomly assigned to the cognitive training group (n=45) and the wait-list control group (n=45). The cognitive training group will receive 10 weeks of process-based multi-task cognitive training and health education twice a week, at 40~60 min per session. While the wait-list control group will only receive 10 weeks of health education during the research period. The effect is measured using the executive function, neuropsychological assessment performance and related brain activity assessed with electroencephalogram parameters (slowness and complexity of the EEG) at baseline, after 10 weeks of training, and a 3-month follow-up.

RESULTS

The study is currently ongoing. Recruitment began in March 2019 and will conclude at the end of 2020. Effects of the process-based multi-task cognitive training on executive function in older adults with MCI will be described in intention-to-treat analysis and protocol set principle. We will also explore the potential long-term effects and transfer effects.

DISCUSSION

If a process-based multi-task cognitive training program results in positive changes to executive function in older adults with MCI, this might provide a viable and potential approach to delay the cognitive decline. Clinical Trial Registration: ChiCTR1900020585. Registered on January 09, 2019. http://www.chictr.org.cn/showproj.aspx?proj=34664.

Comparing different tests to detect early manifestation of prospective memory decline in aging

Objective: Prospective memory (PM) is the ability to remember to perform future intentions. Previous studies have demonstrated that, compared to a younger cohort, healthy older adults have impairments in PM. Considering the importance of early detection of age-related PM decline, the present study aims to compare the performance of healthy older adults using three well-known PM tests commonly used in clinical settings.Method: In the present study, we tested 70 older adults (65-95 years old) using the Cambridge Prospective Memory Test (CAMPROMPT), the Memory for Intentions Screening Test (MIST) and the Royal Prince Alfred Prospective Memory Test (RPA-ProMem). In order to compare performance across tests and the interaction between age and cues, we performed a linear mixed model with random intercept and random slopes. Moreover, additional mixed models with random intercept were run for analyzing the additional information provided by MIST and RPA-ProMem regarding delay responses, response modality effects and type of errors committed.Results: Our data showed a drop in PM performance as age increased detected by all three tests. Furthermore, CAMPROMPT was the most sensitive test to identify differences in PM for event-and time-based cues, at least for participants with 65-77 years old. When data were analyzed in term of delay responses, participants were more accurate for 2 min delay (MIST) and 30 in delay (RPA-ProMem). Participants were less accurate when response modality was "verbal" compared to "action" (MIST) and made more PM errors as age increased.Conclusions: Overall, the study provides important information regarding age-related PM decline and can help researchers as well as clinicians in deciding the preferred test to evaluate PM performance.

Prospective memory and brain metastases: a relevant target for rehabilitation in post-operative patients?

PURPOSE

The study investigated the prospective memory (PM) functioning among patients with brain metastases (BM), eligible for neurosurgy/radiosurgery, and its relationships with depression and quality of life (QoL).

METHODS

This case-healthy-control, cross-sectional study, comprised 160 participants, including 49 patients with BM from various cancers treated with neurosurgery or radiosurgery. They were compared with 111 matched controls on a set of neuropsychological tests, including the MoCA global cognitive test and an experimental PM task 'PROMESSE'. Participants also completed a depression scale (BDI-II), a generic (SF-12) and a specific (QLQ-C30) QoL instrument for cancer patients. Multivariate analyses were conducted on various PM outcomes, in particular on event-based (EBPM) and time-based (TBPM) PM performances.

RESULTS

After adjusting for age and socio-cultural level, patients with BM performed worse than the control on the PM task (p < .0001) [OR 1.05; 95%CI (1.01-1.08)], whatever the location of BM (frontal versus temporal lobe). Patients with infratentorial BM exhibited better TBPM performances than patients with supratentorial BM (p = .02). The global PM performance was positively correlated with the MoCA (r = .45) and the SF-12 global score (r = .34), and negatively with the BDI-II score (r = - .20), the number of BM (r = - .34) and the volumetric of the BM (r = - 29). The TBPM performance was linked to the global QoL (r = .40) in patients.

CONCLUSION

The study showed a significant PM deficit in patients with BM eligible for a neurosurgy/radiosurgery, which is linked to damaged QoL and which likely maintains some depressive affects. Prospective memory rehabilitation program should especially focus on TBPM for post-operative patients with BM.

Investigating prospective memory via eye tracking: No evidence for a monitoring deficit in older adults

Prospective memory (PM) refers to remembering to perform intended actions in the future. Older adults in particular have been shown to be negatively affected by PM tasks that require a high amount of attentional resources (i.e., nonfocal tasks). This age-related PM deficit has been attributed to reduced target monitoring in this age group older adults. However, this conclusion was based on indirect measures of monitoring, such as costs of the ongoing task. The present study set out to 1) investigate older adults' PM target monitoring by, for the first time, employing a direct measure (i.e., eye tracking), 2) assess differences in monitoring between PM tasks that differ in their focality, and 3) examine whether differences in PM monitoring can indeed explain older adults' reduced PM performance in nonfocal tasks. Results demonstrate that while older, but not younger adults, showed reduced performance in a nonfocal PM task, overt monitoring (eye movements) of these groups did not differ between focality conditions. Further analyses showed that older adults' performance was still reduced on the strategically more demanding task after controlling for overt target monitoring (i.e., including only trials in which the participant monitored). In contrast to indirect measures of cue monitoring, our findings illustrate that older adults' deficits on nonfocal PM tasks cannot (exclusively) be explained by reduced monitoring. Instead, processing that takes place after target monitoring are discussed as possible mechanisms underlying older adults' reduced PM performance in nonfocal tasks.

Prospective Memory Predictions in Aging: Increased Overconfidence in Older Adults

INTRODUCTION

This study investigated whether young and older adults can predict their future performance on an event-based prospective memory (PM) task.

METHODS

Metacognitive awareness was assessed by asking participants to give judgments-of-learning (JOLs) on an item-level for the prospective (remembering that something has to be done) and retrospective (remembering what to do) PM component. In addition, to explore possible age differences in the ability to adapt predictions to the difficulty of the task, encoding time and the relatedness between the prospective and the retrospective PM component were varied.

RESULTS

Results revealed that both age groups were sensitive to our task manipulations and adapted their predictions appropriately. Moreover, item-level JOLs indicated that for the retrospective component, young and older adults were equally accurate and slightly overconfident. For the prospective component, predictions were fairly accurate in young adults, while older adults were overconfident. Thus, results suggest that general overconfidence is increased in older adults and concerns both components of PM.

DISCUSSION

Findings regarding the conceptual differences between the prospective and retrospective components of a PM task, as well as the link between aging and metamemory in PM are discussed.

Prospective memory under acute stress: The role of (output) monitoring and ongoing-task demands

Prospective memory (PM) refers to the ability to postpone retrieval and execution of intended actions until the appropriate situation (PM cue) has come, while engaging in other ongoing activities or tasks. In everyday live we often perform PM tasks in stressful situations. While it has been shown that acute stress does not impair PM-cue identification and intention retrieval, little is known about acute stress effects on PM performance and memory for having performed an action (output monitoring) under varying ongoing-task demands. Here we investigated this in eighty healthy participants who performed event-based PM tasks during low- and high-demanding ongoing working memory tasks after having undergone either a standardized stress induction (Maastricht Acute Stress Test) or a standardized control protocol. Successful stress induction in the stress group compared to the no-stress group was confirmed by increased salivary cortisol, an indicator of stress-related hypothalamus-pituitaryadrenal axis activity, throughout the event-based PM tasks. Nevertheless, not-only PM-cue identification but also output monitoring remained fully intact after stress induction. The absence of these effects was independent of ongoing-task demands. Nonetheless, we replicated recent findings of a stress-induced reduction in performance cost of monitoring for PM-cue occurrences. Taken together our findings suggest that acute stress alters PM monitoring by enhancing selective attention, decreasing PM response thresholds or by shifting performance towards more automatic processes in PM, while not affecting PM-cue identification and output monitoring.

Do importance instructions improve time-based prospective remembering in autism spectrum conditions?

This study explored the impact of motivation on the memory for delayed intentions (so-called, prospective memory, PM) in autistic individuals. Specifically, we were interested in the effects of personal (i.e., receiving a reward) as compared to social motivation (i.e., performing a favour for someone). Given the well-established theory of mind deficits in autism, we expected autistic individuals to benefit more strongly from personal than social importance manipulations, whereas the opposite pattern was predicted for controls. Sixty-one adolescents with autism and 61 typically developing adolescents participated, with each group distributed equally to one of the three motivation conditions of standard, social and personal reward. Participants worked on a 2-back picture-based ongoing task in which a time-based PM task was embedded. A mixed 2 (Group) x 3 (Motivation condition) analysis of covariance with age, verbal and non-verbal abilities as covariates and correct PM responses as dependent variable indicated solely a main effect of group, with controls outperforming the autism group. In contrast to our expectations, there was no main effect of condition, no significant interaction, and none of the covariates had any significant impact. However, further planned analyses revealed that controls only outperformed autistic individuals in the personal reward condition. Controls performed significantly best when a personal reward was promised, whereas there were no significant differences between the motivation conditions for autistic individuals. Findings are discussed in terms of underlying processes.

The Effect of Stereotype Threat on Age Differences in Prospective Memory Performance: Differential Effects on Focal Versus Nonfocal Tasks

OBJECTIVES

The current study examined the effects of stereotype threat on prospective memory (PM) performance in younger versus older adults by using a focal (i.e., low cognitive demands) and a nonfocal (i.e., high cognitive demands) PM task.

METHOD

Sixty younger and 60 older adults performed an event-based PM task, in which task instructions were experimentally manipulated. Half of the participants received instructions that emphasized the memory component of the task (memory condition; i.e., high stereotype threat for older adults) whereas the other half was instructed that the task evaluated participants' reading-ability (reading condition; i.e., low stereotype threat).

RESULTS

Older adults' PM performance was worse than younger adults' only in the memory condition and these effects were specific for nonfocal PM cues as well as for old-old adults.

DISCUSSION

Conceptually, this indicates that stereotype threat particularly impacts age effects for cognitive processes associated with executive control and that this particularly affects old-old adults. Therefore, the current findings illustrate for the first time that age differences in PM can be influenced by stereotype threat and suggest changes in controlled attention as possible cognitive pathway.

Prospective memory (partially) mediates the link between ADHD symptoms and procrastination

Individuals with attention deficit hyperactivity disorder (ADHD) often show poor planning and poor organization of tasks and activities which has been related to reduced memory for delayed intentions (prospective memory) and procrastination-in addition to other cognitive or motivational factors. This study set out to bring the fields of prospective memory and procrastination research together and to explore possible relations between the two constructs in ADHD. Twenty-nine adults with ADHD and 24 healthy controls performed several laboratory-based and real-life prospective memory tasks and filled in questionnaires measuring their symptom severity and procrastination behaviour. Overall, individuals' with ADHD showed clear deficits in everyday prospective memory performance. Individuals with ADHD recalled and executed less of their own real-life intentions. Moreover, there were clear links between everyday prospective memory performance and reported procrastination behaviour, and everyday prospective memory performance mediated the link between ADHD symptoms and procrastination behaviour.

Do Inhibitory Control Demands Affect Event-Based Prospective Memory Performance in ADHD?

OBJECTIVE

Empirical evidence on prospective memory (PM) in ADHD is inconsistent. Differential findings have been related to differential executive control demands. This study aimed at exploring the impact of inhibitory control on event-based PM performance in ADHD.

METHOD

Eighteen adults with ADHD and 18 controls performed a word categorization task with an embedded event-based PM task. In addition, participants performed an acoustically presented task that put either low or high loads on inhibitory control processes.

RESULTS

Inhibitory load did not differentially affect PM performance: Across both inhibitory load conditions, individuals with ADHD showed reduced PM performance when compared with controls. Moreover, inhibitory load did not influence PM performance across both groups.

CONCLUSION

Possibly, full inhibitory control resources are not necessary during the entire duration of an event-based PM task, but may suffice to be employed after cue detection when needing to interrupt the ongoing task. (J. of Att. Dis. 2019; 23(1) 51-56).

The relationship between episodic future thinking and prospective memory in middle childhood: Mechanisms depend on task type

Episodic future thinking (EFT), the ability to imagine experiencing a future event, and prospective memory (PM), the ability to remember and carry out a planned action, are core aspects of future-oriented cognition that have individually been the focus of research attention in the developmental literature. However, the relationship between EFT and PM, including the extent to which it varies with PM task type, remains poorly delineated, particularly in middle childhood. The current study tested this relationship in 62 typically developing children aged 8-12 years. Results indicated that EFT ability was significantly related to performance on three types of PM tasks (regular and irregular event based and regular time based). Age was not found to moderate the relationship. Children's performance on the retrospective memory component of the PM tasks mediated the relationship between EFT ability and their performance on three types of PM tasks. For irregular event-based tasks, however, EFT made an additional significant contribution. This study adds to the limited empirical literature supporting a relationship between EFT and PM in this age band and supports theoretical models arguing that EFT ability may support PM performance by strengthening the encoding of PM task details in retrospective memory. However, additional mechanisms were also indicated for irregular event-based PM tasks, possibly involving strengthening of cue-context associations. These data show for the first time that the contribution of EFT to children's PM performance varies across task types. This study provides an important and novel contribution to current understanding of the processes that underlie PM development.

The interplay of intention maintenance and cue monitoring in younger and older adults' prospective memory

The retention phase of a prospective memory (PM) task poses different challenges, including demands to store or maintain an intended action and to realize the right moment for action execution. The interplay of these processes in younger and older adults has not been explored so far. In this study, the authors examined the impact of maintenance load and task focality on PM in 84 younger and in 83 older adults. Results indicated that PM performance and ongoing task response times were strongly affected by maintenance load and age. However, a focality effect only emerged when maintenance load was low but not when attentional resources were deployed for maintaining a more demanding intention. These findings suggest that maintenance and monitoring requirements compete for similar attentional resources. Furthermore, maintenance load may affect postretrieval processes through its impact on working-memory resources, which can restrain the typical advantage of focal over nonfocal PM tasks.

Acute pain disrupts prospective memory cue detection processes

Prospective memory refers to the planning, retention, retrieval, and execution of intentions for future behaviours and it is integral to the enterprise of daily living. Although prospective memory relies upon retrospective memory and executive processes often disrupted by pain, limited research has explored the influence of acute or chronic pain on the ability to complete prospective memory tasks. In the present study we investigated the influence of acute pain on prospective memory tasks that varied in their demands on executive processes (i.e., non-focal versus focal prospective memory cues). Complex-span working memory tasks were also administered to examine whether individual differences in working memory capacity moderated any negative impact of pain on prospective memory. Acute pain significantly impaired prospective memory performance in conditions that encouraged non-focal strategic processing of prospective memory cues, but not in conditions that encouraged more spontaneous focal processing. Individual differences in working memory capacity did not moderate the effect of acute pain on non-focal prospective memory. These findings provide new insights into prospective memory dysfunction created by painful experiences.