Changes in Neural Connectivity and Memory Following a Yoga Intervention for Older Adults: A Pilot Study

Evaluating the Feasibility and Impact of a Yoga Intervention on Cognition, Physical Function, Physical Activity, and Affective Outcomes in People Living With HIV: Protocol for a Randomized Pilot Trial

Background

Despite lower mortality rates due to combination antiretroviral therapy, people living with HIV (PLWH) are grappling with increasingly complex health issues, including cognitive impairments in areas such as memory, attention, processing speed, and motor function. Yoga has been shown to be an effective form of exercise and mindfulness-based stress reduction for many clinical populations. However, no randomized trials have evaluated the impact of yoga on cognitive and physical function among PLWH.

Objective

The aim of this pilot randomized trial was to determine the feasibility of a yoga intervention to lay the groundwork for a full-scale, multisite, community-based trial for PLWH. Specific objectives are to (1) assess the feasibility of study protocol and procedures, (2) compare cognition in the yoga group with the usual care control group after 12 weeks of the intervention in PLWH, and (3) compare the effects of the 12-week yoga intervention versus control on balance, walking speed, physical activity, mental health, medication adherence, and quality of life among PLWH.

Methods

We propose a pilot randomized trial with 2 parallel groups (yoga versus control). We will recruit 25 PLWH (>35 years) from community and health organizations in Halifax, Canada. After baseline assessment with blinded assessors, participants will be randomly assigned to the yoga or control group, using a random computer generator. Participants in the yoga group will engage in supervised 60-min group-based yoga sessions 3 times a week for 12 weeks at a yoga studio. Participants in the control group will maintain their current physical activity levels throughout the study.

Results

As per the Consolidated Standards of Reporting Trials extension for pilot studies, means of all outcomes, mean change, and 95% CIs will be calculated for each group separately. Two-tailed independent t tests and Fisher exact tests will be used to compare groups at baseline. We will analyze quantitative postintervention questionnaire responses using Chi-square tests, and open-ended responses will be analyzed thematically. Intention-to-treat and per-protocol analyses will be used to analyze secondary variables. Changes in outcome variables will be examined between groups and within groups. Effect sizes will be reported for each outcome. A priori adherence and satisfaction criteria will be met if participants attend >70% of the yoga sessions and if >70% of the participants are satisfied with the intervention as determined by a postparticipation questionnaire. Study enrollment began in January 2018, with results expected for October 2019.

Conclusions

This pilot randomized trial will be the first to investigate the feasibility and effect of a yoga intervention on cognitive and physical outcomes among PLWH. This work will inform the feasibility of further investigations in terms of capacity building, participant recruitment and retention, and assessment and intervention protocols.

Trial Registration

ClinicalTrials.gov NCT03071562; https://clinicaltrials.gov/ct2/show/NCT03071562 (Archived by WebCite at http://www.webcitation.org/785sfhWkw)

International Registered Report Identifier (IRRID)

DERR1-10.2196/13818

Impact of mind-body interventions in older adults with mild cognitive impairment: a systematic review

ABSTRACTBackground:Mind-body interventions have been associated with a range of positive outcomes in older adults with mild cognitive impairment (MCI). The aim of the present study was to review the impact of different non-pharmacological programs based on mind-body intervention for older adults with MCI.

METHODS

A comprehensive search method as required by the Cochrane Collaboration has been performed through the following databases: Google Scholar, Science Direct, PubMed, PsycINFO, MEDLINE, EMBASE, CINHAL, Cochrane, Ebsco. We included the studies that evaluated the impact of mind-body interventions such as mindfulness or meditation, yoga, Tai Chi and Qigong on cognitive function and everyday functionality of non-hospitalized adults aged 55 years or over with MCI.

RESULTS

Nine studies met the inclusion criteria. Results indicated that mind-body interventions improved cognitive function, everyday activities functioning, and mindfulness, as well as resulting in a moderate reduction in fall risk, depression and stress and lower risk of dementia at one year.

CONCLUSION

Several mind-body interventions focused broadly on mindfulness, yoga and Tai Chi training have been studied. This review shows that mind-body interventions improved cognitive function and everyday activities functioning, memory, resilience and mindfulness in older adults with MCI. However, the conclusions faced limitations, such as small sample size, heterogeneity of outcome measures, lack of an active control group and absence of long-term follow up. Further high-quality evidence is needed in order to determine whether mind-body interventions are cost-effective for improving cognitive decline in older adults with MCI and for delaying the rapid progression from MCI to Alzheimer or other types of dementia.

What are the known effects of yoga on the brain in relation to motor performances, body awareness and pain? A narrative review

OBJECTIVE

The current body of literature was reviewed to evaluate the effects of yoga on the brain in relation to motor performance, body awareness and pain.

BACKGROUND

Yoga has been increasingly popular in the Western countries especially for its unique integration of the mind and body. Yoga has been studied more intensely in the last decade. Although it has been shown to improve cognitive functions, few studies have looked into the effects of yoga on improving motor performance, body awareness or pain and the possible underlying brain mechanisms associated with them.

METHODS

A search of the current literature was made using keywords such as: "yoga brain motor", "yoga brain pain", "effects yoga brain" and "effects yoga brain motor performance". The findings were then discussed in relation to motor performance, body awareness and pain and their reported mechanisms of action on the brain.

RESULTS

A total of 61 articles were selected, out of which 29 were excluded because they did not meet our criteria. A total of thirty-two articles were included in this review, which we further subdivided by focus: motor performance (n = 10), body awareness (n = 14) and pain (n = 8).

DISCUSSION

Our review shows that yoga has a positive effect on learning rate, speed and accuracy of a motor task by increasing attention and decreasing stress through a better control of sensorimotor rhythms. Yoga also seems to improve sensory awareness and interoception, regulate autonomic input, increase parasympathetic activity and promote self-regulation. Yoga was also shown to reduce the threat signal, increase pain tolerance, decrease pain unpleasantness and decrease the anxiety and distress associated with pain. Those changes are associated with the recruitment of specific brain areas such as the insula, the amygdala and the hippocampus.

CONCLUSION

Based on the studies reviewed in this report, we found that the practice of yoga seems to facilitate motor learning, to increase body awareness and to decrease pain. These are associated with a wide variety of changes in terms of brain activity and structure. Further studies are necessary to reveal its precise mechanism of action on the brain and to validate its wider application in clinical settings.

Impact of yoga based lifestyle intervention on psychological stress and quality of life in the parents of children with retinoblastoma

BACKGROUND

Childhood cancers are associated with a psychological burden to the parents and hence, decline their mental and physical health and overall quality of life.

PURPOSE

The purpose of the present study is to investigate the impact of 12-weeks yoga based lifestyle intervention on psychological stress and quality of life in the parents of children affected with retinoblastoma.

METHOD

Single arm prospective clinical trial conducted from October 2015 to October 2017 at the Laboratory for Molecular Reproduction and Genetics, Department of Anatomy, All India Institute of Medical Sciences, New Delhi, India. A pre-tested 12-weeks yoga based lifestyle intervention included asanas (physical postures), pranayama (breathing exercises), dhyana (meditation), relaxation techniques, lectures and films on yoga, interactive sessions and individualized advice was administered to the participants.

RESULTS

12-weeks of yoga based lifestyle intervention programme leads to a significant improvement in psychological stress and overall quality of life in the parents of retinoblastoma patients. There was a significant improvement in all the domains (physical health, psychological health, social relationships, and environment) of WHOQOL-BREF from baseline (day 0) to 12-weeks of yoga based lifestyle intervention. Yoga based lifestyle intervention also led to a significant increase in the levels of brain derived neurotrophic factor, dehydroepiandrosterone sulphate, sirtuin 1 and decreased the cortisol and IL-6 levels.

CONCLUSION

Yoga based lifestyle intervention reduced the severity of psychological stress and resulted in improvement in overall quality of life and upregulation in levels of systemic biomarkers of neuroplasticity. YBLI may serve as a beneficial therapy and may also act as an effective medium for better stress management to develop better coping strategies in the parents of retinoblastoma patients.

The Effects of Yoga on Patients with Mild Cognitive Impairment and Dementia: A Scoping Review

Yoga is an ancient mind body practice. Although yoga has been used as a complementary health approach for enhancing wellness and addressing a variety of health issues, little is known about the impact of yoga on cognitive functioning in adults with mild cognitive impairment (MCI) and dementia. We conducted a literature review to examine the impact of yoga on persons with MCI and dementia. Eight studies were identified that reported on yoga as either the primary intervention or one component of a multi-component intervention in samples of persons with MCI or dementia. Results suggest that yoga may have beneficial effects on cognitive functioning, particularly on attention and verbal memory. Further, yoga may affect cognitive functioning through improved sleep, mood, and neural connectivity. There are a number of limitations of the existing studies, including a lack of intervention details, as well as variability in the frequency/duration and components of the yoga interventions. A further complicating issue is the role of various underlying etiologies of cognitive impairment. Despite these limitations, providers may consider recommending yoga to persons with MCI or dementia as a safe and potentially beneficial complementary health approach.

Effects of Mind-Body Exercises on Cognitive Function in Older Adults: A Meta-Analysis

BACKGROUND/OBJECTIVES

Mind-body exercise has positive effects on cognitive performance, according to clinical observation and experts' recommendations. However, its potential benefits for the cognitive function of aging adults are uncertain and still lack systematic estimations. Therefore, we conducted a systematic review and meta-analysis to evaluate the overall efficacy and effectiveness of mind-body exercises for cognitive performance in aging individuals with or without cognitive impairment.

DESIGN

A systematic review and meta-analysis.

SETTING AND PARTICIPANTS

We searched related trials through June 2018 from four databases: Medline, Embase, PsycINFO (all via Ovid), and the Cochrane Library/Central Register of Controlled Trials.

MEASUREMENTS

Methodological quality was assessed using the Cochrane Risk of Bias Tool. A meta-analysis of comparative effects was performed using Review Manager v.5.3 software, and publication bias was examined using Egger's test.

RESULTS

A total of 32 randomized controlled trials with 3624 participants were ultimately included in this meta-analysis. The results revealed that mind-body exercises as a whole had benefits in improving global cognition compared with that of the control group (mean difference [MD] = 0.92; 95% confidence interval [CI] = 0.33-1.51; p = .002) and were more effective than control interventions in promoting cognitive flexibility (MD = -8.80; 95% CI = -15.22 to -2.38; p = .007), working memory (MD = 0.32; 95% CI = 0.01-0.64; p = .05), verbal fluency (standardized mean difference [SMD] = 0.27; 95% CI = 0.09-0.45; p = .003), and learning (SMD = 0.24; 95% CI = 0.10-0.39; p = .001) on cognitively intact or impaired older adults. In dose-subgroup analysis, only moderate exercise intensity (60-120 min per week) significantly increased global cognition scores compared with those of the control group (MD = 1.15; 95% CI = 0.34-1.97; p = .006).

CONCLUSION

Mind-body exercises, especially tai chi and dance mind-body exercise, are beneficial for improving global cognition, cognitive flexibility, working memory, verbal fluency, and learning in cognitively intact or impaired older adults. Moderate intensity is recommended as the optimal dose for older adults. J Am Geriatr Soc 67:749-758, 2019.

CD34 and CD117 Stemness of Lineage-Negative Cells Reverses Memory Loss Induced by Amyloid Beta in Mouse Model

A majority of the neurodegenerative disorders including Alzheimer's disease are untreatable and occur primarily due to aging and rapidly changing lifestyles. The rodent Alzheimer's disease models are critical for investigating the underlying disease pathology and screening of novel therapeutic targets in preclinical settings. We aimed to characterize the stemness properties of human umbilical cord blood (hUCB) derived lineage-negative (Lin−) stem cells based on CD34 and CD117 expression as well as surface morphology using flow cytometry and scanning electron microscopy, respectively. The efficacy of the stem cells was tested by its capacity to rescue the injury caused by intrahippocampal delivery of varying doses of amyloid beta. The hUCB Lin− stem cells reversed memory loss due to Aβ42-induced injury more effectively at micromolar concentration, and not picomolar concentration. More studies are required to delineate the underlying molecular events associated with hUCB Lin− stem cells.

Resilience and amygdala function in older healthy and depressed adults

BACKGROUND

Previous studies suggest that low emotional resilience may correspond with increased or over-active amygdala function. Complementary studies suggest that emotional resilience increases with age; older adults tend to have decreased attentional bias to negative stimuli compared to younger adults. Amygdala nuclei and related brain circuits have been linked to negative affect, and depressed patients have been demonstrated to have abnormal amygdala function.

METHODS

In the current study, we correlated psychological resilience measures with amygdala function measured with resting-state arterial spin-labelled (ASL) and blood-oxygenation-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) in older adults with and without depression. Specifically, we targeted the basolateral, centromedial, and superficial nuclei groups of the amygdala, which have different functions and brain connections.

RESULTS

High levels of psychological resilience correlated with lower basal levels of amygdala activity measured with ASL fMRI. High resilience also correlated with decreased connectivity between amygdala nuclei and the ventral default-mode network independent of depression status. Instead, lower depression symptoms were associated with higher connectivity between the amygdalae and dorsal frontal networks.

LIMITATIONS

Future multi-site studies with larger sample size and improved neuroimaging technologies are needed. Longitudinal studies that target resilience to naturalistic stressors will also be a powerful contribution to the field.

CONCLUSIONS

Our results suggest that resilience in older adults is more closely related to function in ventral amygdala networks, while late-life depression is related to reduced connectivity between the amygdala and dorsal frontal regions.

Tai Chi Chuan and Baduanjin Increase Grey Matter Volume in Older Adults: A Brain Imaging Study

The aim of this study is to investigate and compare how 12-weeks of Tai Chi Chuan and Baduanjin exercise can modulate brain structure and memory function in older adults. Magnetic resonance imaging and memory function measurements (Wechsler Memory Scale-Chinese revised, WMS-CR) were applied at both the beginning and end of the study. Results showed that both Tai Chi Chuan and Baduanjin could significantly increase grey matter volume (GMV) in the insula, medial temporal lobe, and putamen after 12-weeks of exercise. No significant differences were observed in GMV between the Tai Chi Chuan and Baduanjin groups. We also found that compared to healthy controls, Tai Chi Chuan and Baduanjin significantly improved visual reproduction subscores on the WMS-CR. Baduanjin also improved mental control, recognition, touch, and comprehension memory subscores of the WMS-CR compared to the control group. Memory quotient and visual reproduction subscores were both associated with GMV increases in the putamen and hippocampus. Our results demonstrate the potential of Tai Chi Chuan and Baduanjin exercise for the prevention of memory deficits in older adults.

The Effects of Mindfulness on Older Adults with Mild Cognitive Impairment

Background

The current lack of an effective cure for dementia would exacerbate its prevalence and incidence globally. Growing evidence has linked mindfulness to cognitive and psychological improvements that could be relevant for mild cognitive impairment (MCI).

Objective

To investigate whether mindfulness practice can improve health outcomes of MCI.

Methods

The study is the first longitudinal mixed-methods observational study with a one-year follow-up period, that customized an eight-week group-based mindfulness training program for older adults with MCI (n = 14). Measures included cognitive function, psychological health, trait mindfulness, adherence to mindfulness practice, and everyday activities functioning as assessed at pre-intervention, post-intervention, and one-year follow-up. Repeated measures ANOVAs, Pearson's correlation analyses, and Mann-Whitney U tests were performed.

Results

The MCI participants showed significant improvements in cognitive function (p < 0.05) and trait mindfulness (p < 0.05) after completing the intervention. Between program intervention and one-year follow-up (59 weeks), positive correlations were found between their cognitive function (p < 0.05) and everyday activities functioning (p < 0.05) with the duration of mindfulness meditation; and between trait mindfulness and the level of informal mindfulness practice (p < 0.05). Those who meditated more during these 59 weeks, showed greater improvements in cognitive function (p < 0.05) and everyday activities functioning (p < 0.05), with large effect sizes at the one-year follow-up. Qualitative findings will be reported separately.

Conclusion

Long-term mindfulness practice may be associated with cognitive and functional improvements for older adults with MCI. Mindfulness training could be a potential efficacious non-pharmacological therapeutic intervention for MCI.

Hypoxia in CNS Pathologies: Emerging Role of miRNA-Based Neurotherapeutics and Yoga Based Alternative Therapies

Cellular respiration is a vital process for the existence of life. Any condition that results in deprivation of oxygen (also termed as hypoxia) may eventually lead to deleterious effects on the functioning of tissues. Brain being the highest consumer of oxygen is prone to increased risk of hypoxia-induced neurological insults. This in turn has been associated with many diseases of central nervous system (CNS) such as stroke, Alzheimer's, encephalopathy etc. Although several studies have investigated the pathophysiological mechanisms underlying ischemic/hypoxic CNS diseases, the knowledge about protective therapeutic strategies to ameliorate the affected neuronal cells is meager. This has augmented the need to improve our understanding of the hypoxic and ischemic events occurring in the brain and identify novel and alternate treatment modalities for such insults. MicroRNA (miRNAs), small non-coding RNA molecules, have recently emerged as potential neuroprotective agents as well as targets, under hypoxic conditions. These 18-22 nucleotide long RNA molecules are profusely present in brain and other organs and function as gene regulators by cleaving and silencing the gene expression. In brain, these are known to be involved in neuronal differentiation and plasticity. Therefore, targeting miRNA expression represents a novel therapeutic approach to intercede against hypoxic and ischemic brain injury. In the first part of this review, we will discuss the neurophysiological changes caused as a result of hypoxia, followed by the contribution of hypoxia in the neurodegenerative diseases. Secondly, we will provide recent updates and insights into the roles of miRNA in the regulation of genes in oxygen and glucose deprived brain in association with circadian rhythms and how these can be targeted as neuroprotective agents for CNS injuries. Finally, we will emphasize on alternate breathing or yogic interventions to overcome the hypoxia associated anomalies that could ultimately lead to improvement in cerebral perfusion.

Greater Cortical Thickness in Elderly Female Yoga Practitioners-A Cross-Sectional Study

Yoga, a mind-body activity that requires attentional engagement, has been associated with positive changes in brain structure and function, especially in areas related to awareness, attention, executive functions and memory. Normal aging, on the other hand, has also been associated with structural and functional brain changes, but these generally involve decreased cognitive functions. The aim of this cross-sectional study was to compare brain cortical thickness (CT) in elderly yoga practitioners and a group of age-matched healthy non-practitioners. We tested 21 older women who had practiced hatha yoga for at least 8 years and 21 women naive to yoga, meditation or any mind-body interventions who were matched to the first group in age, years of formal education and physical activity level. A T1-weighted MPRAGE sequence was acquired for each participant. Yoga practitioners showed significantly greater CT in a left prefrontal lobe cluster, which included portions of the lateral middle frontal gyrus, anterior superior frontal gyrus and dorsal superior frontal gyrus. We found greater CT in the left prefrontal cortex of healthy elderly women who trained yoga for a minimum of 8 years compared with women in the control group.

A randomized controlled trial of Kundalini yoga in mild cognitive impairment

BACKGROUND

Global population aging will result in increasing rates of cognitive decline and dementia. Thus, effective, low-cost, and low side-effect interventions for the treatment and prevention of cognitive decline are urgently needed. Our study is the first to investigate the effects of Kundalini yoga (KY) training on mild cognitive impairment (MCI).

METHODS

Older participants (≥55 years of age) with MCI were randomized to either a 12-week KY intervention or memory enhancement training (MET; gold-standard, active control). Cognitive (i.e. memory and executive functioning) and mood (i.e. depression, apathy, and resilience) assessments were administered at baseline, 12 weeks and 24 weeks.

RESULTS

At baseline, 81 participants had no significant baseline group differences in clinical or demographic characteristics. At 12 weeks and 24 weeks, both KY and MET groups showed significant improvement in memory; however, only KY showed significant improvement in executive functioning. Only the KY group showed significant improvement in depressive symptoms and resilience at week 12.

CONCLUSION

KY group showed short- and long-term improvements in executive functioning as compared to MET, and broader effects on depressed mood and resilience. This observation should be confirmed in future clinical trials of yoga intervention for treatment and prevention of cognitive decline (NCT01983930).

The Four Pillars of Alzheimer's Prevention

Much is yet to be discovered about the precise biological changes that cause Alzheimer's, disease, why it progresses more quickly in some than in others, and how the disease can be prevented, slowed, or stopped. And while researchers continue to search for the magic pill that can prevent or halt the spread of amyloid in the brain, our authors believe that changing or modifying one's lifestyle and attitude can make a difference in both prevention and treatment.

A Systematic Review of Intervention Studies Examining Nutritional and Herbal Therapies for Mild Cognitive Impairment and Dementia Using Neuroimaging Methods: Study Characteristics and Intervention Efficacy

Neuroimaging facilitates the assessment of complementary medicines (CMs) by providing a noninvasive insight into their mechanisms of action in the human brain. This is important for identifying the potential treatment options for target disease cohorts with complex pathophysiologies. The aim of this systematic review was to evaluate study characteristics, intervention efficacy, and the structural and functional neuroimaging methods used in research assessing nutritional and herbal medicines for mild cognitive impairment (MCI) and dementia. Six databases were searched for articles reporting on CMs, dementia, and neuroimaging methods. Data were extracted from 21/2,742 eligible full text articles and risk of bias was assessed. Nine studies examined people with Alzheimer's disease, 7 MCI, 4 vascular dementia, and 1 all-cause dementia. Ten studies tested herbal medicines, 8 vitamins and supplements, and 3 nootropics. Ten studies used electroencephalography (EEG), 5 structural magnetic resonance imaging (MRI), 2 functional MRI (fMRI), 3 cerebral blood flow (CBF), 1 single photon emission tomography (SPECT), and 1 positron emission tomography (PET). Four studies had a low risk of bias, with the majority consistently demonstrating inadequate reporting on randomisation, allocation concealment, blinding, and power calculations. A narrative synthesis approach was assumed due to heterogeneity in study methods, interventions, target cohorts, and quality. Eleven key recommendations are suggested to advance future work in this area.

BDNF Responses in Healthy Older Persons to 35 Minutes of Physical Exercise, Cognitive Training, and Mindfulness: Associations with Working Memory Function

Brain-derived neurotrophic factor (BDNF) has a central role in brain plasticity by mediating changes in cortical thickness and synaptic density in response to physical activity and environmental enrichment. Previous studies suggest that physical exercise can augment BDNF levels, both in serum and the brain, but no other study has examined how different types of activities compare with physical exercise in their ability to affect BDNF levels. By using a balanced cross over experimental design, we exposed nineteen healthy older adults to 35-minute sessions of physical exercise, cognitive training, and mindfulness practice, and compared the resulting changes in mature BDNF levels between the three activities. We show that a single bout of physical exercise has significantly larger impact on serum BDNF levels than either cognitive training or mindfulness practice in the same persons. This is the first study on immediate BDNF effects of physical activity in older healthy humans and also the first study to demonstrate an association between serum BDNF responsivity to acute physical exercise and working memory function. We conclude that the BDNF increase we found after physical exercise more probably has a peripheral than a central origin, but that the association between post-intervention BDNF levels and cognitive function could have implications for BDNF responsivity in serum as a potential marker of cognitive health.

Detection and Prevention of Cognitive Decline

Current diagnostic and treatment strategies for cognitive decline can help patients maintain cognitive ability and higher levels of function longer. Despite advances in detection and early treatment strategies, many patients do not receive proper assessments and available therapies. A systematic assessment strategy will increase the likelihood of an accurate diagnosis, which can facilitate pharmacologic and non-pharmacologic treatment plans that can have a meaningful impact on prognosis. Available data support the integration of healthy lifestyle strategies in the treatment plan to help to stabilize symptoms and potentially delay future cognitive decline. While investigators continue to pursue more effective detection, treatment, and prevention strategies, the scientific data support the use of symptomatic drug treatments and recommendations for healthy lifestyle behaviors to improve quality of life and potentially stave off future cognitive decline. Success of such healthy lifestyle programs involves educating participants on the connection between lifestyle and disease prevention, offering enjoyable exercises that target the patient's skill level, and providing feedback that motivates participants to continue their healthy behaviors so they become habits.

Neurochemical and Neuroanatomical Plasticity Following Memory Training and Yoga Interventions in Older Adults with Mild Cognitive Impairment

Behavioral interventions are becoming increasingly popular approaches to ameliorate age-related cognitive decline, but their underlying neurobiological mechanisms and clinical efficiency have not been fully elucidated. The present study explored brain plasticity associated with two behavioral interventions, memory enhancement training (MET) and a mind-body practice (yogic meditation), in healthy seniors with mild cognitive impairment (MCI) using structural magnetic resonance imaging (s-MRI) and proton magnetic resonance spectroscopy (¹H-MRS). Senior participants (age ≥55 years) with MCI were randomized to the MET or yogic meditation interventions. For both interventions, participants completed either MET training or Kundalini Yoga (KY) for 60-min sessions over 12 weeks, with 12-min daily homework assignments. Gray matter volume and metabolite concentrations in the dorsal anterior cingulate cortex (dACC) and bilateral hippocampus were measured by structural MRI and ¹H-MRS at baseline and after 12 weeks of training. Metabolites measured included glutamate-glutamine (Glx), choline-containing compounds (Cho, including glycerophosphocholine and phosphocholine), gamma-aminobutyric acid (GABA), and N-acetyl aspartate and N-acetylaspartyl-glutamate (NAA-NAAG). In total, 11 participants completed MET and 14 completed yogic meditation for this study. Structural MRI analysis showed an interaction between time and group in dACC, indicating a trend towards increased gray matter volume after the MET intervention. ¹H-MRS analysis showed an interaction between time and group in choline-containing compounds in bilateral hippocampus, induced by significant decreases after the MET intervention. Though preliminary, our results suggest that memory training induces structural and neurochemical plasticity in seniors with MCI. Further research is needed to determine whether mind-body interventions like yoga yield similar neuroplastic changes.

The Neural Mechanisms of Meditative Practices: Novel Approaches for Healthy Aging

Objectives

Meditation has been shown to have physical, cognitive, and psychological health benefits that can be used to promote healthy aging. However, the common and specific mechanisms of response remain elusive due to the diverse nature of mind–body practices.

Methods

In this review, we aim to compare the neural circuits implicated in focused-attention meditative practices that focus on present-moment awareness to those involved in active-type meditative practices (e.g., yoga) that combine movement, including chanting, with breath practices and meditation.

Recent Findings

Recent meta-analyses and individual studies demonstrated common brain effects for attention-based meditative practices and active-based meditations in areas involved in reward processing and learning, attention and memory, awareness and sensory integration, and self-referential processing and emotional control, while deactivation was seen in the amygdala, an area implicated in emotion processing. Unique effects for mindfulness practices were found in brain regions involved in body awareness, attention, and the integration of emotion and sensory processing. Effects specific to active-based meditations appeared in brain areas involved in self-control, social cognition, language, speech, tactile stimulation, sensorimotor integration, and motor function.

Summary

This review suggests that mind–body practices can target different brain systems that are involved in the regulation of attention, emotional control, mood, and executive cognition that can be used to treat or prevent mood and cognitive disorders of aging, such as depression and caregiver stress, or serve as “brain fitness” exercise. Benefits may include improving brain functional connectivity in brain systems that generally degenerate with Alzheimer’s disease, Parkinson’s disease, and other aging-related diseases.