Cognitive Training Sustainably Improves Executive Functioning in Middle-Aged Industry Workers Assessed by Task Switching: A Randomized Controlled ERP Study

Well-designed manufacturing work improves some cognitive abilities in individuals with cognitive impairments

Introduction

Employment is recognized as a fundamental human right, which correlates with better physical and mental health. Importantly, well-designed work, which considers the physical, social, and psychological impacts of work, can serve to enhance the cognitive abilities of workers. Although often overlooked, work for individuals with disabilities, including cognitive impairments, is equally important for their physical and mental well-being. What has not been established, however, is whether well-designed work can also enhance the cognitive abilities of individuals with cognitive impairments.

Methods

Using a longitudinal study design, we investigated the impact of well-designed work on the cognitive abilities of 60 participants (operators) at the AMIPI Foundation factories, which employ individuals with cognitive impairments to produce electrical cables and harnesses for the automobile industry. The same operators were assessed at three different time points: upon hiring (n = 60), and after working in the factory for 1 year (n = 41, since 19 left the factory) and 2 years (n = 28, since 13 more left the factory). We used five cognitive tests evaluating: (1) finger and manual dexterity, bimanual dexterity, and procedural memory using the Purdue Pegboard; (2) sustained and selective attention using the Symbol Cancellation Task; (3) short- and long-term declarative verbal memory and long-term verbal recognition memory using Rey's Audio-Verbal Learning Test; (4) short- and long-term visual recognition memory using the Continuous Visual Memory Test; and (5) abstract reasoning using Raven's Standard Progressive Matrices.

Results

We observed improvements in procedural memory, sustained and selective attention, and short- and long-term visual recognition memory after working in the factory for 1 or 2 years. We did not observe improvements in finger or manual dexterity or bimanual dexterity, nor short- or long-term declarative verbal memory or verbal recognition memory, nor abstract reasoning.

Discussion

We conclude that, in addition to improving physical and mental well-being, well-designed manufacturing work can serve as a training intervention improving some types of cognitive functioning in individuals with cognitive impairments.

Effects of cognitive and stress management training in middle-aged and older industrial workers in different socioeconomic settings: a randomized controlled study

Introduction

The demographic change requires longer working lifetime. However, fear of job loss may lead to chronic stress whereas aging and unchallenging work may accelerate cognitive decline and early retirement. Long-time repetitive work led to impairments of cognitive functions in middle-aged and older employees, as demonstrated in a previous study conducted in a large car manufacturer. In the present study, a training concept was implemented to enhance the cognitive and emotional competence of these employees.

Methods

A first group of employees received a trainer-guided cognitive training only, whereas a wait list control group received a cognitive training and stress management training. This design was applied in two independent samples separated by one year either during or after a socioeconomically tense situation of the factory.

Results

In sample 1, with a tense occupational situation, the cognitive training effects occurred with a delay of three months. In contrast, in sample 2, with less critical socioeconomic situation, the training effects occurred immediately and persisted three months later. Stress management training showed reduction of subjectively and objectively measured stress level.

Discussion

The results indicate that effects of cognitive interventions are diminished under chronic stress which can be reduced after a short stress management training. This leads also to enhanced attention and memory in daily life. In contrast, in Sample 2 with less chronic stress, effects of cognitive training were stronger and persisted at least three months later, whereas stress management training had less impact. This suggests that cognitive learning in occupational settings is only efficient at lower stress levels.

The impact of physical fitness, social life, and cognitive functions on work ability in middle-aged and older adults

Objective

Demographic changes encompass societies to maintain the work ability (WA) of aging workforces. The present study explored the relationship between modifiable lifestyle factors, cognitive functions, and their influence on WA, using a multi-group structural equation approach.

Method

Cross-sectional data from 247 middle-aged and 236 older employees from the Dortmund Vital Study were included in this analysis. We proposed a model with three exogenous variables (Physical Fitness, Cognitive Functions, and Social Life), and with WA as the endogenous variable. WA was measured with the Work Ability Index (WAI), which considers job demands and individual physical and mental resources. Multi-group analyses were based on the principles of invariance testing and conducted using robust estimation methods.

Results

Results revealed that Social Life outside work had significant positive effects on WA in both, middle-aged and older adults. Physical Fitness had a significant effect on WA only in middle-aged adult, and Cognitive Functions had no significant influence on WA in either group. In older adults, Physical Fitness correlated with Cognitive Functions, whereas in middle-aged adults, Cognitive Functions marginally correlated with Social Life.

Conclusions

Our results underline the importance of an active social life outside the workplace for WA, regardless of the employees’ age. The influence of Physical Fitness on WA changes with increasing age, indicating the necessity to have a differentiated view of age effects and interacting influencing factors. Our research contributes to the knowledge of how WA could be most effectively promoted in different age groups.

Clinicaltrials.gov NCT05155397; https://clinicaltrials.gov/ct2/show/NCT05155397.

Feasibility of a Home-Based Task-Switching Training in Middle-Aged Caregivers

The current study aimed at investigating feasibility of a self-administered task-switching training in a middle-aged working population. Eighty-one caregivers (41–62 years old) were instructed to train at home 8 times either within a 7- or 14-day interval. Only 56.7% performed more than 50% of the instructed number of training sessions. However, compliant caregivers (who completed more than 4 training sessions) showed significant training gains and transfer to an untrained task-switching task. Although transfer effects to other cognitive tasks were not found, trained participants tended to report fewer everyday memory failures than a control group. In conclusion, the implementation of a home-based task-switching training in everyday life of caregivers is possible. However, there is only limited evidence for generalization of results of previous laboratory studies. Adherence and transfer to other cognitive tasks are discussed as important challenges in conveying laboratory findings into real life.

Electrophysiological predictors and indicators of contingency management treatment response: Rationale and design for the ways of rewarding abstinence project (WRAP)

Background

Electrophysiological measures can predict and reflect substance use treatment response. Veterans are disproportionately affected by disorders of addiction; cocaine use disorder (CUD) being particularly problematic due to high relapse rates and the absence of approved pharmacotherapies. Prize-based Contingency Management (PBCM) is an evidence-based behavioral intervention for CUD, involving incentives for cocaine abstinence but treatment response is variable. Measurement-based adaptation of PBCM has promise to improve effectiveness but remains to be usefully developed.

Methods

This trial aims to determine if individuals with distinct neurocognitive profiles differentially benefit from one of two existing versions of PBCM. CUD patients will be randomized into treatment-as-usual or 12-weeks of PBCM using either monetary or tangible prize incentives. Prior to randomization, EEG will be used to assess response to monetary versus tangible reward; EEG and cognitive-behavioral measures of working memory, cognitive control, and episodic future thinking will also be acquired. Substance use and treatment engagement will be monitored throughout the treatment interval and assessments will be repeated at post-treatment.

Discussion

Results of this trial may elucidate individual differences contributing to PBCM treatment response and reveal predictors of differential benefits from existing treatment variants. The design also affords the opportunity to evaluate treatment-related changes in neurocognitive functioning over the course of PBCM. Our model posits that PBCM scaffolds future-oriented goal representation and self-control to support abstinence. Individuals with poorer functioning may be less responsive to abstract monetary reward and will therefore achieve better outcomes with respect to abstinence and treatment engagement when tangible incentives are utilized.

Effectiveness of a Computerized Cognitive Training Program for Reducing Head Impact Kinematics in Youth Ice Hockey Players

Cognitive training (CT) is an effective technique to improve neurological performance, but has not been investigated as a head impact primary prevention strategy. The purpose of this study was to investigate the CT's effectiveness in reducing head impact kinematics in youth ice hockey players. Twenty youth were divided into two groups: a CT and Control group. The CT group performed two 30-minute sessions of IntelliGym CT weekly for 20 weeks and the control group performed two 30-minute sessions weekly evaluating hockey videos. The dependent variables, number of head impacts, cumulative linear acceleration (CLA) and rotational acceleration (CRA) and mean linear and rotation peak acceleration, were compared with repeated measures ANOVAs, with post-hoc for main effect of time for each group, between the first and second half of the season. There were significant interactions for number of head impacts (p = 0.014) and CLA (p = 0.043) and post-hoc testing identified reductions in the second half of the season for the CT, but not control, group. There were no interactions for CRA, mean peak linear acceleration, and mean peak rotational acceleration. These preliminary results suggest CT may be an effective primary prevention strategy to reduce head impacts and cumulative linear acceleration in youth ice hockey players.

Effects of adaptive and non-adaptive three-week executive control training on interference control: Evidence from the N2, CRN, and ERN

The current pilot study investigated if interference control can be improved by a three-week at-home training comprising a flanker and a n-back task in healthy adults, thus exploring the training's suitability for future clinical application, i.e. as a treatment augmentation for psychological disorders. As training gains are assumed to be modulated by the amount of mismatch between task demands and brain resources, an adaptive and a non-adaptive training were contrasted in separate experiments. In the adaptive training, task difficulty was continuously adapted to participants' performance. In the non-adaptive training procedure, task difficulty remained stable on the lowest difficulty level. As deficits in interference control in psychological disorders often predominantly manifest on the electrophysiological level, the impact of the training procedures on medio-frontal negativities (N2, CRN, ERN) was investigated in addition to behavioral measures. The adaptive training led to significant improvements in interference control, as reflected in reduced response times and error rates in incompatible trials. This was accompanied by specific and complementary changes in medio-frontal negativities: After the adaptive training the N2 in incompatible trials was larger and the CRN in incompatible trials was reduced. The non-adaptive training procedure led to generally faster response times but also an increased error rate, indicating a speed-accuracy trade-off. This was accompanied by global changes to medio-frontal negativities irrespective of compatibility, possibly indicating task disengagement. Taken together, the current studies demonstrate that an adaptive training procedure can improve interference control thereby opening up possible clinical applications.

Effects of multi-domain cognitive training on working memory retrieval in older adults: behavioral and ERP evidence from a Chinese community study

Working memory (WM) is a fundamental cognitive function that typically declines with age. Previous studies have shown that targeted WM training has the potential to improve WM performance in older adults. In the present study, we investigated whether a multi-domain cognitive training program that was not designed to specifically target WM could improve the behavioral performance and affect the neural activity during WM retrieval in healthy older adults. We assigned healthy older participants (70-78 years old) from a local community into a training group who completed a 3-month multi-domain cognitive training and a control group who only attended health education lectures during the same period. Behavioral and electroencephalography (EEG) data were recorded from participants while performing an untrained delayed match or non-match to category task and a control task at a pre-training baseline session and a post-training follow-up session. Behaviorally, we found that participants in the training group showed a trend toward greater WM performance gains than participants in the control group. Event-related potential (ERP) results suggest that the task-related modulation of P3 during WM retrieval was significantly enhanced at the follow-up session compared with the baseline session, and importantly, this enhancement of P3 modulation was only significant in the training group. Furthermore, no training-related effects were observed for the P2 or N2 component during WM retrieval. These results suggest that the multi-domain cognitive training program that was not designed to specifically target WM is a promising approach to improve WM performance in older adults, and that training-related gains in performance are likely mediated by an enhanced modulation of P3 which might reflect the process of WM updating.

Multidomain Cognitive Training Transfers to Attentional and Executive Functions in Healthy Older Adults

Healthy aging is associated with deficits in focused and sustained attention and executive functions. However, cognitive training (CT) provides a promising method to counteract these deficits. In the present randomized controlled study, we examined to what extent CT regimes can improve attention, verbal skills, and inhibition capacities. Over a period of 16 weeks, healthy older adults (65 years and older, mean: 70 years) received a trainer-guided multidomain paper-and-pencil and computerized CT. Pre- and post-training, a battery of psychometric tests was applied that measured the critical functions. This study used two control groups: a passive control and an active control group performing a relaxation training. Compared to a passive control group, the CT led to enhanced performance in the attentional endurance test and the interference list of the Stroop test, whereas no benefits in verbal and crystalized tests were found. Similar effects were found on the attentional endurance compared to the active control group. Additionally, word fluency was enhanced after CT, but the improvement in the Stroop test did not reach significance compared to the active control. The contents of CT were dissimilar to the psychometric tests showing far transfer, whereas no transfer to attentional or memory functions in the daily life assessed by the Cognitive Failures Questionnaire was found. This demonstrates specific gains of multidomain CT on cognitive functions not explicitly trained and lack of transfer to daily activities.

The effectiveness of e-interventions on fall, neuromuscular functions and quality of life in community-dwelling older adults: A systematic review and meta-analysis

BACKGROUND

Falls in older adults result in serious, life-limiting consequences. An increasing number of fall prevention interventions have used technology to reduce the number of falls in community-dwelling adults. Various types of e-interventions are being tested in clinical trials and in the community. These include telehealth, exergames, cognitive games, socialized training, smart home systems and non-conventional balance training. Currently, no systematic review and meta-analysis has assessed the overall effectiveness of e-interventions and compared the effectiveness of the different types.

OBJECTIVES

The aim of this review was to synthesize best available evidence concerning the effectiveness of e-interventions on fall, neuromuscular functions and quality of life in community-dwelling older adults.

METHODS

A rigorous three-step search was conducted in nine online databases for published and unpublished randomized controlled trials studying e-interventions. Studies were screened and assessed for individual and overall risk of bias by two independent reviewers. Six fall-related outcomes were evaluated in the meta-analysis: fall risk, balance, lower extremity strength, fall efficacy, cognitive function and health-related quality of life. Subgroup and sensitivity analysis were conducted during meta-analysis.

RESULTS

Thirty-one studies fit the eligibility criteria and had an overall 74.7% low risk of bias. A total of 4,877 older adults from 17 countries were included in narrative synthesis and meta-analysis. Telehealth combined with exercise programmes and smart home systems were able to reduce fall risk significantly (risk ratio=0.79, 95% CI [0.72, 0.86]). E-interventions also significantly improved balance and fall efficacy (standardized mean difference=0.28, 95% CI [0.04, 0.53]). However, lower extremity strength, cognitive function and health-related quality of life did not show significant improvements.

CONCLUSION

Telehealth combined with exercise and smart home systems demonstrated the best evidence of effectiveness in reduction of falls in community-dwelling older adults. Future research should focus on forecasting falls using smart home technology and Artificial Intelligence, and testing promising e-interventions on larger samples to improve the strength of evidence of fall prevention by e-interventions.

Effects of multidomain versus single-domain training on executive control and memory in older adults: study protocol for a randomized controlled trial

BACKGROUND

Previous research suggests that both cognitive training and physical exercise help to maintain brain health and cognitive functions that decline with age. Some studies indicate that combined interventions may produce larger effects than each intervention alone. The aim of this study is to investigate the effects of combined cognitive and physical training compared to cognitive training and physical training alone on executive control and memory functions in healthy older adults.

OBJECTIVES

The main objectives of this four-arm randomized controlled trial (RCT) are: to investigate the synergetic effects of a simultaneous, group-based multidomain training program that combines cognitive video-game training with physical exercise, in comparison to those produced by cognitive training combined with physical control activity, physical training combined with cognitive control activity, or a combination of both control activities; to investigate whether event-related potential latencies of the P2 component are shorter and N2 and P3b components assessed in a memory-based task switching task are enhanced after training; and to find out whether possible enhancements persist after a 3-month period without training.

METHODS

In this randomized, single-blind, controlled trial, 144 participants will be randomly assigned to one of the four combinations of cognitive training and physical exercise. The cognitive component will be either video-game training (cognitive intervention, CI) or video games not specifically designed to train cognition (cognitive control, CC). The physical exercise component will either emphasize endurance, strength, and music-movement coordination (exercise intervention, EI) or stretching, toning, and relaxation (exercise control, EC).

DISCUSSION

This RCT will investigate the short and long-term effects of multidomain training, compared to cognitive training and physical training alone, on executive control and memory functions in healthy older adults, in comparison with the performance of an active control group.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03823183. Registered on 21 January 2019.

Computerised cognitive training for 12 or more weeks for maintaining cognitive function in cognitively healthy people in late life

BACKGROUND

Increasing age is associated with a natural decline in cognitive function and is the greatest risk factor for dementia. Cognitive decline and dementia are significant threats to independence and quality of life in older adults. Therefore, identifying interventions that help to maintain cognitive function in older adults or that reduce the risk of dementia is a research priority. Cognitive training uses repeated practice on standardised exercises targeting one or more cognitive domains and may be intended to improve or maintain optimal cognitive function. This review examines the effects of computerised cognitive training interventions lasting at least 12 weeks on the cognitive function of healthy adults aged 65 or older and has formed part of a wider project about modifying lifestyle to maintain cognitive function. We chose a minimum 12 weeks duration as a trade-off between adequate exposure to a sustainable intervention and feasibility in a trial setting.

OBJECTIVES

To evaluate the effects of computerised cognitive training interventions lasting at least 12 weeks on cognitive function in cognitively healthy people in late life.

SEARCH METHODS

We searched to 31 March 2018 in ALOIS (www.medicine.ox.ac.uk/alois), and we performed additional searches of MEDLINE, Embase, PsycINFO, CINAHL, ClinicalTrials.gov, and the WHO Portal/ICTRP (www.apps.who.int/trialsearch), to ensure that the search was as comprehensive and as up-to-date as possible to identify published, unpublished, and ongoing trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs, published or unpublished, reported in any language. Participants were cognitively healthy people, and at least 80% of the study population had to be aged 65 or older. Experimental interventions adhered to the following criteria: intervention was any form of interactive computerised cognitive intervention - including computer exercises, computer games, mobile devices, gaming console, and virtual reality - that involved repeated practice on standardised exercises of specified cognitive domain(s) for the purpose of enhancing cognitive function; the duration of the intervention was at least 12 weeks; cognitive outcomes were measured; and cognitive training interventions were compared with active or inactive control interventions.

DATA COLLECTION AND ANALYSIS

We performed preliminary screening of search results using a 'crowdsourcing' method to identify RCTs. At least two review authors working independently screened the remaining citations against inclusion criteria. At least two review authors also independently extracted data and assessed the risk of bias of included RCTs. Where appropriate, we synthesised data in random-effects meta-analyses, comparing computerised cognitive training (CCT) separately with active and inactive controls. We expressed treatment effects as standardised mean differences (SMDs) with 95% confidence intervals (CIs). We used GRADE methods to describe the overall quality of the evidence for each outcome.

MAIN RESULTS

We identified eight RCTs with a total of 1183 participants. The duration of the interventions ranged from 12 to 26 weeks; in five trials, the duration of intervention was 12 or 13 weeks. The included studies had moderate risk of bias, and the overall quality of evidence was low or very low for all outcomes. We compared CCT first against active control interventions, such as watching educational videos. Negative SMDs favour CCT over control. Trial results suggest slight improvement in global cognitive function at the end of the intervention period (12 weeks) (standardised mean difference (SMD) -0.31, 95% confidence interval (CI) -0.57 to -0.05; 232 participants; 2 studies; low-quality evidence). One of these trials also assessed global cognitive function 12 months after the end of the intervention; this trial provided no clear evidence of a persistent effect (SMD -0.21, 95% CI -0.66 to 0.24; 77 participants; 1 study; low-quality evidence). CCT may result in little or no difference at the end of the intervention period in episodic memory (12 to 17 weeks) (SMD 0.06, 95% CI -0.14 to 0.26; 439 participants; 4 studies; low-quality evidence) or working memory (12 to 16 weeks) (SMD -0.17, 95% CI -0.36 to 0.02; 392 participants; 3 studies; low-quality evidence). Because of the very low quality of the evidence, we are very uncertain about the effects of CCT on speed of processing and executive function. We also compared CCT to inactive control (no interventions). We found no data on our primary outcome of global cognitive function. At the end of the intervention, CCT may lead to slight improvement in episodic memory (6 months) (mean difference (MD) in Rivermead Behavioural Memory Test (RBMT) -0.90 points, 95% confidence interval (CI) -1.73 to -0.07; 150 participants; 1 study; low-quality evidence) but can have little or no effect on executive function (12 weeks to 6 months) (SMD -0.08, 95% CI -0.31 to 0.15; 292 participants; 2 studies; low-quality evidence), working memory (16 weeks) (MD -0.08, 95% CI -0.43 to 0.27; 60 participants; 1 study; low-quality evidence), or verbal fluency (6 months) (MD -0.11, 95% CI -1.58 to 1.36; 150 participants; 1 study; low-quality evidence). We could not determine any effects on speed of processing because the evidence was of very low quality. We found no evidence on quality of life, activities of daily living, or adverse effects in either comparison.

AUTHORS' CONCLUSIONS

We found low-quality evidence suggesting that immediately after completion of the intervention, small benefits of CCT may be seen for global cognitive function when compared with active controls, and for episodic memory when compared with an inactive control. These benefits are of uncertain clinical importance. We found no evidence that the effect on global cognitive function persisted 12 months later. Our confidence in the results was low, reflecting the overall quality of the evidence. In five of the eight trials, the duration of the intervention was just three months. The possibility that more extensive training could yield larger benefit remains to be more fully explored. We found substantial literature on cognitive training, and collating all available scientific information posed problems. Duration of treatment may not be the best way to categorise interventions for inclusion. As the primary interest of older people and of guideline writers and policymakers involves sustained cognitive benefit, an alternative would be to categorise by length of follow-up after selecting studies that assess longer-term effects.

[Multimodular Cognitive Training for Nursing Staff Aged 50+: Initial Results of a Pilot Study on Feasibility and Efficacy]

THE AIM OF THE STUDY

was the assessment of the feasibility of a cognitive training program for employees of care 50+.

METHOD

A cognitive training program (13 h, 5 sessions) was conducted with 15 nurses of the University Hospital Munich (KUM). Acceptance of and effects on cognitive and psychological performance were determined.

RESULTS

The measure was well accepted and received positive ratings. In addition, there were significant improvements in cognitive performance and self-efficacy.

CONCLUSION

The training program can be implemented on a regular basis; initial results providing evidence in support of positive training effects must be confirmed in future randomized controlled trials.

Dispositional forgiveness and stress as primary correlates of executive functioning in adults

The purpose of this study was to explore the physical, social, and mental health correlates of executive functioning in adults. Our sample consisted of 250 adults aged 18–55 years who participated in a survey. Participants reported on their physical health behaviors, family closeness, and mental health. Using hierarchical linear regression, the final model explained 41 percent of executive functioning in adults. Dispositional forgiveness of situations, stress, and living in a single-family home were the only significant correlates of executive functioning. These results are useful for better understanding possible mechanisms through which to improve executive functioning in adults.

Computerised cognitive training for maintaining cognitive function in cognitively healthy people in late life

BACKGROUND

Increasing age is associated with a natural decline in cognitive function and is also the greatest risk factor for dementia. Cognitive decline and dementia are significant threats to independence and quality of life in older adults. Therefore, identifying interventions that help to maintain cognitive function in older adults or to reduce the risk of dementia is a research priority. Cognitive training uses repeated practice on standardised exercises targeting one or more cognitive domains and is intended to maintain optimum cognitive function. This review examines the effect of computerised cognitive training interventions lasting at least 12 weeks on the cognitive function of healthy adults aged 65 or older.

OBJECTIVES

To evaluate the effects of computerised cognitive training interventions lasting at least 12 weeks for the maintenance or improvement of cognitive function in cognitively healthy people in late life.

SEARCH METHODS

We searched to 31 March 2018 in ALOIS (www.medicine.ox.ac.uk/alois) and performed additional searches of MEDLINE, Embase, PsycINFO, CINAHL, ClinicalTrials.gov, and the WHO Portal/ICTRP (www.apps.who.int/trialsearch) to ensure that the search was as comprehensive and as up-to-date as possible, to identify published, unpublished, and ongoing trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs, published or unpublished, reported in any language. Participants were cognitively healthy people, and at least 80% of the study population had to be aged 65 or older. Experimental interventions adhered to the following criteria: intervention was any form of interactive computerised cognitive intervention - including computer exercises, computer games, mobile devices, gaming console, and virtual reality - that involved repeated practice on standardised exercises of specified cognitive domain(s) for the purpose of enhancing cognitive function; duration of the intervention was at least 12 weeks; cognitive outcomes were measured; and cognitive training interventions were compared with active or inactive control interventions.

DATA COLLECTION AND ANALYSIS

We performed preliminary screening of search results using a 'crowdsourcing' method to identify RCTs. At least two review authors working independently screened the remaining citations against inclusion criteria. At least two review authors also independently extracted data and assessed the risk of bias of included RCTs. Where appropriate, we synthesised data in random-effect meta-analyses, comparing computerised cognitive training (CCT) separately with active and inactive controls. We expressed treatment effects as standardised mean differences (SMDs) with 95% confidence intervals (CIs). We used GRADE methods to describe the overall quality of the evidence for each outcome.

MAIN RESULTS

We identified eight RCTs with a total of 1183 participants. Researchers provided interventions over 12 to 26 weeks; in five trials, the duration of intervention was 12 or 13 weeks. The included studies had a moderate risk of bias. Review authors noted a lot of inconsistency between trial results. The overall quality of evidence was low or very low for all outcomes.We compared CCT first against active control interventions, such as watching educational videos. Because of the very low quality of the evidence, we were unable to determine any effect of CCT on our primary outcome of global cognitive function or on secondary outcomes of episodic memory, speed of processing, executive function, and working memory.We also compared CCT versus inactive control (no interventions). Negative SMDs favour CCT over control. We found no studies on our primary outcome of global cognitive function. In terms of our secondary outcomes, trial results suggest slight improvement in episodic memory (mean difference (MD) -0.90, 95% confidence interval (CI) -1.73 to -0.07; 150 participants; 1 study; low-quality evidence) and no effect on executive function (SMD -0.08, 95% CI -0.31 to 0.15; 292 participants; 2 studies; low-quality evidence), working memory (MD -0.08, 95% CI -0.43 to 0.27; 60 participants; 1 study; low-quality evidence), or verbal fluency (MD -0.11, 95% CI -1.58 to 1.36; 150 participants; 1 study; low-quality evidence). We could not determine any effects on speed of processing at trial endpoints because the evidence was of very low quality.We found no evidence on quality of life, activities of daily living, or adverse effects in either comparison.

AUTHORS' CONCLUSIONS

We found little evidence from the included studies to suggest that 12 or more weeks of CCT improves cognition in healthy older adults. However, our limited confidence in the results reflects the overall quality of the evidence. Inconsistency between trials was a major limitation. In five of the eight trials, the duration of intervention was just three months. The possibility that longer periods of training could be beneficial remains to be more fully explored.

Computerised cognitive training for maintaining cognitive function in cognitively healthy people in midlife

BACKGROUND

Normal aging is associated with changes in cognitive function that are non-pathological and are not necessarily indicative of future neurocognitive disease. Low cognitive and brain reserve and limited cognitive stimulation are associated with increased risk of dementia. Emerging evidence now suggests that subtle cognitive changes, detectable years before criteria for mild cognitive impairment are met, may be predictive of future dementia. Important for intervention and reduction in disease risk, research also suggests that engaging in stimulating mental activity throughout adulthood builds cognitive and brain reserve and reduces dementia risk. Therefore, midlife (defined here as 40 to 65 years) may be a suitable time to introduce cognitive interventions for maintaining cognitive function and, in the longer term, possibly preventing or delaying the onset of clinical dementia.

OBJECTIVES

To evaluate the effects of computerised cognitive training interventions lasting at least 12 weeks for maintaining or improving cognitive function in cognitively healthy people in midlife.

SEARCH METHODS

We searched up to 31 March 2018 in ALOIS (www.medicine.ox.ac.uk/alois), the specialised register of the Cochrane Dementia and Cognitive Improvement Group (CDCIG). We ran additional searches in MEDLINE, Embase, PsycINFO, CINAHL, ClinicalTrials.gov, and the WHO Portal/ICTRP at www.apps.who.int/trialsearch, to ensure that the search was as comprehensive and as up-to-date as possible, to identify published, unpublished, and ongoing trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) or quasi-RCTs, published or unpublished, reported in any language. Participants were cognitively healthy people between 40 and 65 years of age (80% of study population within this age range). Experimental interventions adhered to the following criteria: intervention was any form of interactive computerised cognitive intervention - including computer exercises, computer games, mobile devices, gaming console, and virtual reality - that involved repeated practice on standardised exercises of specified cognitive domain(s) for the purpose of enhancing cognitive function; duration of the intervention was at least 12 weeks; cognitive outcomes were measured; and cognitive training interventions were compared with active or inactive control interventions.

DATA COLLECTION AND ANALYSIS

For preliminary screening of search results, we used a 'crowd' method to identify RCTs. At least two review authors working independently screened remaining citations against inclusion criteria; independently extracted data; and assessed the quality of the included trial, using the Cochrane risk of bias assessment tool. We used GRADE to describe the overall quality of the evidence.

MAIN RESULTS

We identified one eligible study that examined the effect of computerised cognitive training (CCT) in 6742 participants over 50 years of age, with training and follow-up duration of six months. We considered the study to be at high risk of attrition bias and the overall quality of the evidence to be low.Researchers provided no data on our primary outcome. Results indicate that there may be a small advantage for the CCT group for executive function (mean difference (MD) -1.57, 95% confidence interval (CI) -1.85 to -1.29; participants = 3994; low-quality evidence) and a very small advantage for the control group for working memory (MD 0.09, 95% CI 0.03 to 0.15; participants = 5831; low-quality evidence). The intervention may have had little or no effect on episodic memory (MD -0.03, 95% CI -0.10 to 0.04; participants = 3090; low-quality evidence).

AUTHORS' CONCLUSIONS

We found low-quality evidence from only one study. We are unable to determine whether computerised cognitive training is effective in maintaining global cognitive function among healthy adults in midlife. We strongly recommend that high-quality studies be undertaken to investigate the effectiveness and acceptability of cognitive training in midlife, using interventions that last long enough that they may have enduring effects on cognitive and brain reserve, and with investigators following up long enough to assess effects on clinically important outcomes in later life.

Computerised cognitive training for preventing dementia in people with mild cognitive impairment

BACKGROUND

The number of people living with dementia is increasing rapidly. Clinical dementia does not develop suddenly, but rather is preceded by a period of cognitive decline beyond normal age-related change. People at this intermediate stage between normal cognitive function and clinical dementia are often described as having mild cognitive impairment (MCI). Considerable research and clinical efforts have been directed toward finding disease-modifying interventions that may prevent or delay progression from MCI to clinical dementia.

OBJECTIVES

To evaluate the effects of at least 12 weeks of computerised cognitive training (CCT) on maintaining or improving cognitive function and preventing dementia in people with mild cognitive impairment.

SEARCH METHODS

We searched to 31 May 2018 in ALOIS (www.medicine.ox.ac.uk/alois) and ran additional searches in MEDLINE, Embase, PsycINFO, CINAHL, ClinicalTrials.gov, and the WHO portal/ICTRP (www.apps.who.int/trialsearch) to identify published, unpublished, and ongoing trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs in which cognitive training via interactive computerised technology was compared with an active or inactive control intervention. Experimental computerised cognitive training (CCT) interventions had to adhere to the following criteria: minimum intervention duration of 12 weeks; any form of interactive computerised cognitive training, including computer exercises, computer games, mobile devices, gaming console, and virtual reality. Participants were adults with a diagnosis of mild cognitive impairment (MCI) or mild neurocognitive disorder (MND), or otherwise at high risk of cognitive decline.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias of the included RCTs. We expressed treatment effects as mean differences (MDs) or standardised mean differences (SMDs) for continuous outcomes and as risk ratios (RRs) for dichotomous outcomes. We used the GRADE approach to describe the overall quality of evidence for each outcome.

MAIN RESULTS

Eight RCTs with a total of 660 participants met review inclusion criteria. Duration of the included trials varied from 12 weeks to 18 months. Only one trial used an inactive control. Most studies were at unclear or high risk of bias in several domains. Overall, our ability to draw conclusions was hampered by very low-quality evidence. Almost all results were very imprecise; there were also problems related to risk of bias, inconsistency between trials, and indirectness of the evidence.No trial provided data on incident dementia. For comparisons of CCT with both active and inactive controls, the quality of evidence on our other primary outcome of global cognitive function immediately after the intervention period was very low. Therefore, we were unable to draw any conclusions about this outcome.Due to very low quality of evidence, we were also unable to determine whether there was any effect of CCT compared to active control on our secondary outcomes of episodic memory, working memory, executive function, depression, functional performance, and mortality. We found low-quality evidence suggesting that there is probably no effect on speed of processing (SMD 0.20, 95% confidence interval (CI) -0.16 to 0.56; 2 studies; 119 participants), verbal fluency (SMD -0.16, 95% CI -0.76 to 0.44; 3 studies; 150 participants), or quality of life (mean difference (MD) 0.40, 95% CI -1.85 to 2.65; 1 study; 19 participants).When CCT was compared with inactive control, we obtained data on five secondary outcomes, including episodic memory, executive function, verbal fluency, depression, and functional performance. We found very low-quality evidence; therefore, we were unable to draw any conclusions about these outcomes.

AUTHORS' CONCLUSIONS

Currently available evidence does not allow us to determine whether or not computerised cognitive training will prevent clinical dementia or improve or maintain cognitive function in those who already have evidence of cognitive impairment. Small numbers of trials, small samples, risk of bias, inconsistency between trials, and highly imprecise results mean that it is not possible to derive any implications for clinical practice, despite some observed large effect sizes from individual studies. Direct adverse events are unlikely to occur, although the time and sometimes the money involved in computerised cognitive training programmes may represent significant burdens. Further research is necessary and should concentrate on improving methodological rigour, selecting suitable outcomes measures, and assessing generalisability and persistence of any effects. Trials with long-term follow-up are needed to determine the potential of this intervention to reduce the risk of dementia.

Event-related neural oscillation changes following reasoning training in individuals with Mild Cognitive Impairment

Emerging evidence suggests cognitive training programs targeting higher-order reasoning may strengthen not only cognitive, but also neural functions in individuals with Mild Cognitive Impairment (MCI). However, research on direct measures of training-induced neural changes, derivable from electroencephalography (EEG), is limited. The current pilot study examined effects of Gist Reasoning training (n = 16) compared to New Learning training (n = 16) in older adults with amnestic MCI on measures of event-related neural oscillations (theta and alpha band power) corresponding to Go/NoGo tasks during basic and superordinate semantic categorization. EEG data were recorded while participants performed the Go/NoGo task pre- and post-training, and power in theta and alpha frequency bands was examined. Both groups were comparable at pre-training on all measures and both groups showed greater event-related theta synchronization post-training. Furthermore, the Gist Reasoning group had enhanced event-related desynchronization in low-frequency alpha band (8-10 Hz) on response inhibition (NoGo) trials and high-frequency alpha band (11-13 Hz) on response execution (Go) trials during superordinate categorization, relative to the New Learning group. These findings suggest that Gist Reasoning training in MCI impacted neural processing linked to strategic processing of Go and NoGo trials during the more complex superordinate categorization task. Targeting higher-order top-down cognitive processing seems to better harness residual neuroplastic potential in MCI. ClinicalTrials.gov ID: NCT02588209.

What Does the n-Back Task Measure as We Get Older? Relations Between Working-Memory Measures and Other Cognitive Functions Across the Lifespan

Working memory (WM) declines with increasing age. The WM capacity is often measured by means of the computerized version of the n-back task. Although the n-back task is widely used in aging research, little is known about its construct validity and specific cognitive functions involved in this task. Moreover, to date, no studies analyzed the construct validity as a function of age. To this end, we conducted a study in a sample of N = 533 individuals aged between 20 and 80 years. The sample was divided into three age groups: young (20-40), middle-aged (41-60), and old (61-80 years). A number of psychometric tests was selected that measure attention, memory, and executive control to elucidate the impact of these constructs on n-back performance. A series of correlation analyses was conducted to assess the relationship between n-back performance and specific cognitive functions in each age group separately. The results show a progressive increase in reaction times and a decrease in the proportion of detected targets from young to old subjects. Age-related impairments were also found in all psychometric tests except for the vocabulary choice test measuring crystallized intelligence. Most importantly, correlations yielded different age-related patterns of functions contributing to performance in the n-back task: whereas performance was most related to executive functions in young age, a combination of attentional and executive processes was associated with performance in middle-aged subjects. In contrast, in older age, mainly attentional, verbal memory, and updating and to a lesser extent executive processes seem to play a crucial role in the n-back task, suggesting a shift of processing strategies across the lifespan.

ERP and Behavioral Effects of Physical and Cognitive Training on Working Memory in Aging: A Randomized Controlled Study

Working memory (WM) performance decreases with age. A promising method to improve WM is physical or cognitive training. The present randomized controlled study is aimed at evaluating the effects of different training methods on WM. A sample of 141 healthy older adults (mean age 70 years) was assigned to one of four groups: physical training, cognitive training, a social control group, and a no-contact control group. The participants trained for four months. Before and after the training, n-back task during an EEG recording was applied. The results show that cognitive training enhanced the target detection rate in the 2-back task. This was corroborated by an increased number of repeated digits in the backward digit-span test but not in other memory tests. The improvement of WM was supported by an increased P3a prior to a correct target and an increased P3b both in nontarget and target trials. No ERP effects in the physical and no-contact control groups were found, while a reduction of P3a and P3b was found in the social control group. Thus, cognitive training enhances frontal and parietal processing related to the maintenance of a stored stimulus for subsequent matching with an upcoming stimulus and increases allocation of cognitive resources. These results indicate that multidomain cognitive training may increase WM capacity and neuronal activity in older age.

A Randomized Controlled ERP Study on the Effects of Multi-Domain Cognitive Training and Task Difficulty on Task Switching Performance in Older Adults

Executive functions are subject to a marked age-related decline, but have been shown to benefit from cognitive training interventions. As of yet, it is, however, still relatively unclear which neural mechanism can mediate training-related performance gains. In the present electrophysiological study, we examined the effects of multi-domain cognitive training on performance in an untrained cue-based task switch paradigm featuring Stroop color words: participants either had to indicate the word meaning of Stroop stimuli (word task) or perform the more difficult task of color naming (color task). One-hundred and three older adults (>65 years old) were randomly assigned to a training group receiving a 4-month multi-domain cognitive training, a passive no-contact control group or an active (social) control group receiving a 4-month relaxation training. For all groups, we recorded performance and EEG measures before and after the intervention. For the cognitive training group, but not for the two control groups, we observed an increase in response accuracy at posttest, irrespective of task and trial type. No training-related effects on reaction times were found. Cognitive training was also associated with an overall increase in N2 amplitude and a decrease of P2 latency on single trials. Training-related performance gains were thus likely mediated by an enhancement of response selection and improved access to relevant stimulus-response mappings. Additionally, cognitive training was associated with an amplitude decrease in the time window of the target-locked P3 at fronto-central electrodes. An increase in the switch positivity during advance task preparation emerged after both cognitive and relaxation training. Training-related behavioral and event-related potential (ERP) effects were not modulated by task difficulty. The data suggest that cognitive training increased slow negative potentials during target processing which enhanced the N2 and reduced a subsequent P3-like component on both switch and non-switch trials and irrespective of task difficulty. Our findings further corroborate the effectiveness of multi-domain cognitive training in older adults and indicate that ERPs can be instrumental in uncovering the neural processes underlying training-related performance gains.