Mindfulness enhances cognitive functioning: a meta-analysis of 111 randomized controlled trials

BACKGROUND

Currently no comprehensive meta-analysis of MBI efficacy on global and unique cognitive subdomains exist.

METHOD

Examined the effects of MBIs on global cognition and 15 cognitive subdomains. Inclusion criteria: meditation naïve participants; randomized controlled trial; outcome included one objective or subjective cognitive functioning measure; primary focus was teaching mindfulness skills. Exclusion criteria: inadequate data; one-session ; control condition contained any MBI component. Robust variance estimation and moderator analyses controlling for presence of treatment fidelity were conducted.

RESULTS

One-hundred-and-eleven RCTs (n = 9,538) met eligibility criteria. MBIs had small-to-moderate significant effects on global cognition, executive attention, working memory accuracy, inhibition accuracy, shifting accuracy, sustained attention, and subjective cognitive functioning (vs. waitlist/no-treatment, g = 0.257-0.643; vs. active controls, g = 0.192-0.394). MBIs did not impact executive functioning (EF) latency indices, verbal fluency, processing speed, episodic memory, and cognitive error. Treatment effects were stronger for those with elevated psychiatric symptoms vs. healthy controls, and medical samples, studies with complete-case (vs. intention-to-treat) analysis, face-to-face (vs. self-guided) delivery, and non-standard (vs. standard MBI).

CONCLUSION

MBIs consistently yielded small-to-moderate yet practically meaningful effect sizes on global cognition and six cognitive subdomains that captured accuracy vs. latency-based indices of EF and sustained accuracy.

Effects of engagement, persistence and adherence on cognitive training outcomes in older adults with and without cognitive impairment: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Limited understanding exists regarding the influences of engagement, persistence and adherence on the efficacy of cognitive training for age-related cognitive decline and neurodegenerative cognitive impairment.

METHODS

This study conducted a meta-analysis of randomised controlled trials (RCTs). We systematically searched MEDLINE, PubMed, Web of Science, Embase and CINAHL databases from 1 January 2012 to 13 June 2023, and included RCTs assessing the effects of cognitive training in older adults, both with and without cognitive impairment. Hedges' g with a 95% confidence interval (CI) was used to synthesise cognitive training effect sizes on various neuropsychological tests. Subgroup analyses were conducted based on variables including engagement, persistence, adherence and cognitive conditions of normal cognition, mild cognitive impairment (MCI) or neurodegenerative dementia.

RESULTS

This meta-analysis included 55 RCTs with 4,455 participants with cognitive conditions spanning normal cognition, MCI and neurodegenerative dementia. The mean age of participants was 73.9 (range: 65.7-84.5) years. Overall, cognitive training showed a significant cross-domain effect (Hedges' g = 0.286, 95% CI: 0.224-0.348). Training effects are significant when engagement or persistence rates exceed 60% or when adherence rates exceed 80%. Higher levels of persistence are required to achieve significant training effects in memory, visuospatial ability and reasoning than in executive function and attention and language. Higher persistence is also required for older adults with normal cognition to achieve significant training gains compared to those with cognitive impairment.

CONCLUSIONS

This systematic review highlights the critical roles of engagement, persistence and adherence in augmenting the efficacy of cognitive training.

Agility training to integratively promote neuromuscular, cardiorespiratory and cognitive function in healthy older adults: a one-year randomized-controlled trial

BACKGROUND

Exercise training recommendations for seniors include the targeted training of strength, balance, endurance and flexibility domains. Agility training (AT) is conceptualized as a multi-component and time-efficient training framework for older adults to improve physical, functional and cognitive health domains that are relevant for maintaining activities of daily living. The aim of this one-year trial was to comparatively evaluate the effects of agility training on physical and cognitive function.

METHODS

Seventy-nine healthy older adults (AT: 61.5% female, 70.8 ± 4.8 years, 27.7 ± 4.2 kg/m2; CG: 60.5% female, 69.6 ± 4.7 years, 27.5 ± 4.4 kg/m2) took part in this one-year randomized controlled intervention and were either assigned to the agility training group (AT) with two weekly 60 min AT sessions or to the control group (CG), receiving no treatment. Participants were assessed pre, intermediate and post intervention for strength and power, balance, gait speed under multi-task conditions, aerobic capacity as well as cognitive performance. Linear mixed effects models were used to analyze the effect of treatment over time.

RESULTS

Fifty-four participants (AG: 25, CG: 29) were analyzed, most drop-outs attributed to COVID-19 (17/30 dropouts). Adherence was good (75%) of 90 offered sessions. Notable effects in favor of AT were found for gait parameters in single (d = 0.355, Δ = 4.3%), dual (d = 0.375, Δ = 6.1%) and triple (d = 0.376, Δ = 6.4%) task conditions, counter movement jump performance (strength and power) (d = 0.203, Δ = 6.9%), static one leg balance (d = 0.256, Δ = 12.33%) and n-back reaction time (cognitive performance) (d = 0.204, Δ = 3.8%). No effects were found for the remaining outcomes (d < 0.175).

CONCLUSION

AT might serve as an integrative training approach for older adults particularly improving gait and lower limb power parameters. It seems suitable to improve a broad range of seniors' health domains and should replace isolated training of these domains. However, individual variation and progression of exercises should be considered when programming agility training providing adequate challenges throughout a long-term intervention for all participants.

TRIAL REGISTRATION

DRKS, DRKS00017469 . Registered 19 June 2019-Retrospectively registered.

The development and evaluation of a self-efficacy enhancement program for older adults with mild cognitive impairment

OBJECTIVE

The aims of this study were to develop a self-efficacy enhancement program and to evaluate its effect on cognitive function, dementia knowledge, self-efficacy, depression, and dementia preventive behaviors in older adults (age ≥ 65 years) with mild cognitive impairment (MCI).

METHODS

This equivalent control group pretest-posttest study was conducted at a tertiary hospital in Seoul, South Korea. Older adults with MCI were randomly allocated to an experimental (EG, n = 16) or control group (CG, n = 16). The EG underwent an 8-week intervention (weekly 60-min session) utilizing self-efficacy enhancement strategies; the CG received usual care. The intervention was comprised of physical, cognitive, and emotional activities and was followed by 4-week maintenance during which both groups engaged in self-learning at home with a dementia preventive guidebook. Outcome data were evaluated at the pretest and 8, 10, and 12 weeks later. This study adhered to the CONSORT guidelines.

RESULTS

There were significant differences in cognitive function, dementia knowledge, self-efficacy, and dementia preventive behaviors, but not in depression between the two groups over the time. Regarding cognitive function subdomains, significant differences were observed in visuospatial/executive, attention, language, and delayed recall.

CONCLUSION

The integrated intervention consisting of physical, cognitive, and emotional activities was effective in improving cognitive function, dementia knowledge, self-efficacy, and dementia preventive behaviors. This suggests that this program can be utilized as an educational program to prevent dementia in older adults with MCI in dementia support centers, public health centers, clinics, and hospitals.

TRIAL REGISTRATION

KCT0006094 in the Clinical Research Information Service. Retrospectively registered 23 April 2021, https://cris.nih.go.kr/cris/search/listDetail.do.

Differential working memory function between phonological and visuospatial strategies: a magnetoencephalography study using a same visual task

Previous studies have reported that, in working memory, the processing of visuospatial information and phonological information have different neural bases. However, in these studies, memory items were presented via different modalities. Therefore, the modality in which the memory items were presented and the strategy for memorizing them were not rigorously distinguished. In the present study, we explored the neural basis of two working memory strategies. Nineteen right-handed young adults memorized seven sequential directions presented visually in a task in which the memory strategy was either visuospatial or phonological (visuospatial/phonological condition). Source amplitudes of theta-band (5-7 Hz) rhythm were estimated from magnetoencephalography during the maintenance period and further analyzed using cluster-based permutation tests. Behavioral results revealed that the accuracy rates showed no significant differences between conditions, while the reaction time in the phonological condition was significantly longer than that in the visuospatial condition. Theta activity in the phonological condition was significantly greater than that in the visuospatial condition, and the cluster in spatio-temporal matrix with p < 5% difference extended to right prefrontal regions in the early maintenance period and right occipito-parietal regions in the late maintenance period. The theta activity results did not indicate strategy-specific neural bases but did reveal the dynamics of executive function required for phonological processing. The functions seemed to move from attention control and inhibition control in the prefrontal region to inhibition of irrelevant information in the occipito-parietal region.

Environments and situations as correlates of eating and drinking among women living with obesity and urban poverty

Objective

One path to improving weight management may be to lessen the self‐control burden of physical activity and healthier food choices. Opportunities to lessen the self‐control burden might be uncovered by assessing the spatiotemporal experiences of individuals in daily context. This report aims to describe the time, place, and social context of eating and drinking and 6‐month weight change among 209 midlife women (n = 113 African–American) with obesity receiving safety‐net primary care.

Methods

Participants completed baseline and 6‐month weight measures, observations and interviews regarding obesogenic cues in the home environment, and up to 12 ecological momentary assessments (EMA) per day for 30 days inquiring about location, social context, and eating and drinking.

Results

Home was the most common location (62%) at times of EMA notifications. Participants reported “yes” to eating or drinking at the time of nearly one in three (31.1% ± 13.2%) EMA notifications. Regarding social situations, being alone was significantly associated with less frequent eating and drinking (OR = 0.75) unless at work in which case being alone was significantly associated with a greater frequency of eating or drinking (OR = 1.43). At work, eating was most common late at night, whereas at home eating was most frequent in the afternoon and evening hours. However, eating and drinking frequency was not associated with 6‐month weight change.

Conclusions

Home and work locations, time of day, and whether alone may be important dimensions to consider in the pursuit of more effective weight loss interventions. Opportunities to personalize weight management interventions, whether digital or human, and lessen in‐the‐moment self‐control burden might lie in identifying times and locations most associated with caloric consumption.

Clinical trial registration: NCT03083964 in clinicaltrials.gov

A Comparison of the Effect of Physical Activity and Cognitive Training on Dual-Task Performance in Older Adults

OBJECTIVES

Studies suggest that cognitive training and physical activity can improve age-related deficits in dual-task performances. However, both of these interventions have never been compared in the same study. This article investigates the improvement in dual-task performance in 2 types of exercise training groups and a cognitive training group and explores if there are specific dual-task components that are more sensitive or more likely to improve following each type of training.

METHODS

Seventy-eight healthy inactive participants older than the age of 60 (M = 69.98, SD = 5.56) were randomized to one of three 12-week training programs: aerobic training (AET) = 26, gross motor abilities (GMA) = 27, and cognition (COG) = 25. Before and after the training program, the participants underwent physical fitness tests, and cognitive evaluations involving a computerized cognitive dual task. The AET consisted of high- and low-intensity aerobic training, the GMA of full-body exercises focusing on agility, balance, coordination, and stretching, and the COG of tablet-based exercises focusing on executive functions.

RESULTS

Repeated-measures analysis of variance on reaction time data revealed a group × time interaction (F(2,75) = 11.91, p < .01) with COG having the greatest improvement, followed by a significant improvement in the GMA group. Secondary analysis revealed the COG to also improve the intraindividual variability in reaction time (F(1,24) = 8.62, p < .01), while the GMA improved the dual-task cost (F(1,26) = 12.74, p < .01).

DISCUSSION

The results show that physical and cognitive training can help enhance dual-task performance by improving different aspects of the task, suggesting that different mechanisms are in play.

The Long-Term Efficacy of Working Memory Training in Healthy Older Adults: A Systematic Review and Meta-Analysis of 22 Randomized Controlled Trials

OBJECTIVES

The long-lasting efficacy of working memory (WM) training has been a controversial and still ardently debated issue. In this meta-analysis, the authors explored the long-term effects of WM training in healthy older adults on WM subdomains and abilities outside the WM domain assessed in randomized controlled studies.

METHOD

A systematic literature search of PubMed, Web of Science, PsycINFO, Cochrane Library, ProQuest, clinicaltrials.gov, and Google Scholar was conducted. Random-effects models were used to quantitatively synthesize the existing data.

RESULTS

Twenty-two eligible studies were included in the meta-analysis. The mean participant age ranged from 63.77 to 80.1 years. The meta-synthesized long-term effects on updating were 0.45 (95% confidence interval = 0.253-0.648, <6 months: 0.395, 0.171-0.619, ≥6 months: 0.641, 0.223-1.058), on shifting, 0.447 (0.246-0.648, <6 months: 0.448, 0.146-0.75, ≥6 months: 0.446, 0.176-0.716); on inhibition, 0.387 (0.228-0.547, <6 months: 0.248, 0.013-0.484, ≥6 months: 0.504, 0.288-0.712); on maintenance, 0.486 (0.352-0.62, <6 months: 0.52, 0.279-0.761, ≥6 months: 0.471, 0.31-0.63).

DISCUSSION

The results showed that WM training exerted robust long-term effects on enhancing the WM system and improving processing speed and reasoning in late adulthood. Future studies are needed to use different tasks of the same WM construct to evaluate the WM training benefits, to adopt more ecological tasks or tasks related to daily life, to improve the external validity of WM training, and to identify the optimal implementation strategy for WM training.

Working memory training effects across the lifespan: Evidence from human and experimental animal studies

Working memory refers to a cognitive function that provides temporary storage and manipulation of the information necessary for complex cognitive tasks. Due to its central role in general cognition, several studies have investigated the possibility that training on working memory tasks could improve not only working memory function but also increase other cognitive abilities or modulate other behaviors. This possibility is still highly controversial, with prior studies providing contradictory findings. The lack of systematic approaches and methodological shortcomings complicates this debate even more. This review highlights the impact of working memory training at different ages on humans. Finally, it demonstrates several findings about the neural substrate of training in both humans and experimental animals, including non-human primates and rodents.