Reduced interference in working memory following mindfulness training is associated with increases in hippocampal volume

The Effect of Mindfulness-Based Interventions on Mental Health and Cognitive Function in Older Adults: A Systematic Review and Meta-Analysis

OBJECTIVES

To assess whether mindfulness-based interventions (MBIs) affect mental health and cognitive abilities in older adults.

METHODS

A systematic search was performed in PubMed, SCOPUS, Web of Science, and Google Scholar up to June 2023. Weight mean difference and 95% confidence intervals were provided as summary statistics.

RESULTS

In total, 26 articles were eligible. Overall, MBIs showed a statistically significant improvement in depression, anxiety, quality of life, and working memory compared to controls. However, no significant effects of MBIs on other cognitive parameters were found. In moderator analysis, less than eight weeks of MBIs showed greater improvement in anxiety and quality of life than longer periods. There was no evidence for publication bias.

DISCUSSION

Mindfulness-based interventions can be an encouraging alternative in place of conventional treatments in improving depression, anxiety, quality of life and working memory in cognition among older adults. However, findings strongly recommend future research to have definite conclusion.

Beneficial effects of mindfulness-based intervention on hippocampal volumes and episodic memory for childhood adversity survivors

Background

Adverse Childhood Experience (ACE) has detrimental impacts on neural development, especially hippocampal morphometry. Mindfulness-Based Interventions (MBI) has been shown to induce adaptive hippocampal changes especially at the subiculum. The present study aims to investigate the effects of MBI on subiculum volumes among ACE survivors, as well as the effects on episodic memory as a probe into hippocampal functionality.

Methods

We analyzed anatomical MRI data and performance indices from an episodic memory task called the Mnemonic Similarity Task (MST) collected from a randomized controlled longitudinal study that compared an 8-week MBI (N = 20) to an active control condition of Stress Management Education (SME) (N = 19). FreeSurfer 6.0 was used for automated hippocampal subfield segmentation and volumetric estimation.

Results

Significant group differences were observed with the volumetric changes of the right whole hippocampus and right subiculum. Only the MBI group showed improved pattern separation capability from MST, which was associated with stress reduction and right subiculum volumetric changes.

Limitations

Modest sample size. MST task was performed outside of MRI.

Conclusions

These findings suggest beneficial effects of MBI for hippocampal volumes and episodic memory, while highlighting the importance of the subiculum for MBI-induced neural and cognitive changes. The subiculum's known role in inhibitory control was interpreted as a potential mechanism for it to exhibit MBI-induced volumetric changes, which sheds light on the potential neural underpinnings of mindfulness meditation for reducing stress reactivity among ACE survivors.

Mindfulness training and exercise differentially impact fear extinction neurocircuitry

BACKGROUND

The ability to extinguish a maladaptive conditioned fear response is crucial for healthy emotional processing and resiliency to aversive experiences. Therefore, enhancing fear extinction learning has immense potential emotional and health benefits. Mindfulness training enhances both fear conditioning and recall of extinguished fear; however, its effects on fear extinction learning are unknown. Here we investigated the impact of mindfulness training on brain mechanisms associated with fear-extinction learning, compared to an exercise-based program.

METHODS

We investigated BOLD activations in response to a previously learned fear-inducing cue during an extinction paradigm, before and after an 8-week mindfulness-based stress reduction program (MBSR, n = 49) or exercise-based stress management education program (n = 27).

RESULTS

The groups exhibited similar reductions in stress, but the MBSR group was uniquely associated with enhanced activation of salience network nodes and increased hippocampal engagement.

CONCLUSIONS

Our results suggest that mindfulness training increases attention to anticipatory aversive stimuli, which in turn facilitates decreased aversive subjective responses and enhanced reappraisal of the memory.

Neural correlates of mindfulness meditation and hypnosis on magnetic resonance imaging: similarities and differences. A scoping review

BACKGROUND

Mindfulness meditation (MM) and hypnosis practices are gaining interest in mental health, but their physiological mechanisms remain poorly understood. This study aimed to synthesize the functional, morphometric and metabolic changes associated with each practice using magnetic resonance imaging (MRI), and to identify their similarities and differences.

METHODS

MRI studies investigating MM and hypnosis in mental health, specifically stress, anxiety, and depression, were systematically screened following PRISMA guidelines from four research databases (PubMed, Web of Science, Embase, PsycINFO) between 2010 and 2022.

RESULTS

In total, 97 references met the inclusion criteria (84 for MM and 13 for hypnosis). This review showed common and divergent points regarding the regions involved and associated brain connectivity during MM practice and hypnosis. The primary commonality between mindfulness and hypnosis was decreased default mode network intrinsic activity and increased central executive network - salience network connectivity. Increased connectivity between the default mode network and the salience network was observed in meditative practice and mindfulness predisposition, but not in hypnosis.

CONCLUSIONS

While MRI studies provide a better understanding of the neural basis of hypnosis and meditation, this review underscores the need for more rigorous studies.

Effects of web-based mindfulness training on psychological outcomes, attention, and neuroplasticity

Mindfulness meditation training (MMT) reliably reduces stress and anxiety while also improving attention. The primary aim of this study was to investigate the relationship between MMT, stress and anxiety reduction, and its impact upon improvements in attention on the behavioral and neuronal levels. As a second aim, we sought to explore any relationship between MMT, attention, and modified states of mind such as flow. 118 healthy, meditation-naïve, participants were either assigned to a 31-day, web-based, MMT or an active control, health training (HT). Participants underwent functional magnetic resonance imaging while performing the attention network test (ANT) to assess functional and behavioural attentional changes, diffusion tensor imaging (DTI) to assess microstructural neuronal changes and completed relevant questionnaires to explore changes in psychological outcomes. Results confirmed a reduction in perceived stress and anxiety levels in the MMT group and significant improvements in the overall reaction time during the ANT, albeit no specific effects on the attentional components were observed. No statistically significant changes were found in the HT group. Interestingly, a significant group-by-time interaction was seen in flow experience. Functional data exhibited an increased activity in the superior frontal gyrus, posterior cingulate cortex, and right hippocampus during the alerting condition of the ANT after the MMT; decreased stress and trait anxiety were significantly correlated with the activation in the right hippocampus, and increased flow was also significantly correlated with all the aforementioned areas. DTI data showed increased fractional anisotropy values in the right uncinate fasciculus indicating white matter microarchitecture improvement between the right hippocampus and frontal areas of the brain. This study, therefore, demonstrates the effectiveness of web-based MMT on overall well-being and attentional performance, while also providing insight into the relationship between psychological outcomes, attention, and neuroplastic changes.

Associations between social health factors, cognitive activity and neurostructural markers for brain health - A systematic literature review and meta-analysis

Social health factors (e.g., social activities or social support) and cognitive activity engagement have been associated with dementia risk, but their neural substrates have not been well established. This systematic review and meta-analysis summarizes the available evidence regarding the association between these factors and cerebral macro- and micro-structure. A comprehensive literature search was conducted in various databases, following predefined criteria. Heterogeneity, risk of publication bias and overall certainty of evidence were assessed using standardized scales and, whenever appropriate, random effects meta-analysis was conducted. Of 6715 identified articles, 43 were included. Overall, consistency of findings was low and methodological heterogeneity high for all outcomes. However, in some studies cognitive and social activities were positively associated with total brain, global and cortical grey matter and hippocampal volume as well as white matter microstructural integrity. Furthermore, structural social network characteristics (e.g., social network size) were associated with regional grey matter volumes, while functional social network characteristics (e.g., social support) were additionally associated with total brain volume. Meta-analyses revealed small but significant partial correlations between cognitive and social activities and hippocampal (three studies; n = 892; rz =0.07) and white matter hyperintensity volume (three studies; n = 2934; rz =-0.04). More prospective studies are needed to assess temporal associations.

Focused attention meditation in healthy adults: A systematic review and meta-analysis of cross-sectional functional MRI studies

Meditation trains the mind to focus attention towards an object or experience. Among different meditation techniques, focused attention meditation is considered foundational for more advanced practices. Despite renewed interest in its functional neural correlates, there is no unified neurocognitive model of focused attention meditation developed via quantitative synthesis of contemporary literature. Hence, we performed a quantitative systematic review and meta-analysis of all functional MRI studies examining focussed attention meditation. Following PRISMA guidelines, 28 studies were included in this review, of which 10 studies (200 participants) were amenable to activation likelihood estimation meta-analysis. We found that regions comprising three key functional brain networks i.e., Default-mode, Salience, and Executive Control, were consistently implicated in focused attention meditation. Furthermore, meditation expertise, mindfulness levels and attentional skills were found to significantly influence the magnitude, but not regional extent, of activation and functional connectivity in these networks. Aggregating all evidence, we present a unified neurocognitive brain-network model of focused attention meditation.

Mindfulness-based cognitive therapy vs. a health enhancement program for the treatment of late-life depression: Study protocol for a multi-site randomized controlled trial

Background

Late-life depression (LLD) affects up to 18% of older adults and has been linked to elevated dementia risk. Mindfulness-based cognitive therapy (MBCT) holds promise for treating symptoms of depression and ameliorating cognitive deficits in older adults. While preliminary findings are promising, a definitive RCT investigating its effects on late life depression and cognition have not yet been conducted. We present a protocol describing a multi-site blinded randomized controlled trial, comparing the effects of MBCT and of an active control, a Health Enhancement Program (HEP), on depressive symptoms, executive functioning, and brain biomarkers of LLD, among several other exploratory outcomes.

Methods

Two-hundred and thirteen (n = 213) patients with LLD will be recruited at various centers in Montreal, QC, Canada. Participants will undergo stratified randomization to either MBCT or HEP intervention groups. We will assess changes in (1) depression severity using the Hamilton Depression Rating Scale (HAM-D17), (2) processing speed and executive functioning, (3) brain biomarkers of LLD (hippocampal volume, default network resting-state functional connectivity and executive network resting-state functional connectivity), and (4) other exploratory physiological and mood-based measures, at baseline (0 weeks), post intervention (8 weeks), and 26 weeks after baseline.

Discussion

The proposed study will assess the clinical potential of MBCT to improve symptoms of depression, as well as examine its impact on cognitive impairments and neurobiological markers, and thus inform its use as a promising adjunct in the treatment of LLD.

Clinical trial registration

www.ClinicalTrials.gov, identifier: NCT05366088.

A Mini-Review of Work Stress and Mindfulness: A Neuropsychological Point of View

Work stress is consistently linked with the deterioration of cognitive and mental health, limitations in everyday workplace performance, and an increased risk of developing diseases. A common thread binding these consequences appears to be stress-associated alterations in neuropsychological functions and affective domains, especially those reliant on hippocampal, prefrontal, and amygdala brain area. Although research broadly supports the claim that the practice of mindfulness meditation for the reduction of the consequences of stress and the promotion of health exert positive effects on workplaces, the precise neuropsychological benefits of Mindfulness-based interventions (MBIs) in the context of organizations remain elusive. In this review, we will analyze the impairments imposed by stress on the brain areas and functions and the benefits of MBIs from a neuropsychological point of view. This is significant since there is a centrality of cognitive functions in core processes necessary for work achievements, such as emotion regulation, problem-solving, and learning. The promotion of wellbeing is a responsibility shared between workers and organizations. Developing healthy environments allows workers to exercise greater control over their work, face work challenges, work productively and develop their talent.

Mindfulness and Behavior Change

Initiating and maintaining behavior change is key to the prevention and treatment of most preventable chronic medical and psychiatric illnesses. The cultivation of mindfulness, involving acceptance and nonjudgment of present-moment experience, often results in transformative health behavior change. Neural systems involved in motivation and learning have an important role to play. A theoretical model of mindfulness that integrates these mechanisms with the cognitive, emotional, and self-related processes commonly described, while applying an integrated model to health behavior change, is needed. This integrative review (1) defines mindfulness and describes the mindfulness-based intervention movement, (2) synthesizes the neuroscience of mindfulness and integrates motivation and learning mechanisms within a mindful self-regulation model for understanding the complex effects of mindfulness on behavior change, and (3) synthesizes current clinical research evaluating the effects of mindfulness-based interventions targeting health behaviors relevant to psychiatric care. The review provides insight into the limitations of current research and proposes potential mechanisms to be tested in future research and targeted in clinical practice to enhance the impact of mindfulness on behavior change.

Physical and mental health outcomes including behavior and attitudes in people having social contacts with COVID-19 patients

The novel coronavirus (COVID-19) infection has spread worldwide since late 2019. People who have social contacts with COVID-19 patients might be at higher risk of physical or mental health problems. This study investigated whether people who had social contacts with COVID-19 patients would have poorer physical or mental outcomes, and different attitudes and behaviors. Chinese adults were recruited to fill in an online survey using snowball sampling during 21^st-26^nd February 2020. Physical symptoms, psychological outcomes, quality of life, COVID-19 related attitudes, and behaviors were measured. The differences in the outcomes between participants who had COVID-19 social contacts and those who had not were analyzed. The survey included 1,447 non-infected eligible participants. Among those, 173 (12.0%) reported at least one confirmed/suspected case in their social contacts. In the multiple regression adjusted for demographic data, the presence of confirmed/suspected infection cases in one’s social contacts was significantly associated with poorer physical and mental outcomes, lower health-related quality of life, and different COVID-19 related attitudes and behaviors (p<0.05). In conclusion, people who had social contacts with COVID-19 patients were at risk of adverse health outcomes. Future studies are needed to understand the long-term impacts. Similarly, strategies to improve health outcomes for these people are needed.

Brief Report: Mindfulness Training for Chinese Adolescents with Autism Spectrum Disorder and Their Parents in Hong Kong

This study investigated the feasibility and preliminary effectiveness of a concurrent mindfulness program (MYmind) on Chinese adolescents with autism spectrum disorder and their parents in Hong Kong, China using a randomized controlled trial with a waitlist control group. Results showed the study had 80% compliance rate, 0% dropout rate, and 89% response rate. Between-group comparisons showed mindfulness had trend effects on parent’s rumination (g = 1.16), mindful parenting (d = 0.6), parenting style (d = 0.59), and parenting stress (d = 0.5). The study demonstrated the feasibility of the MYmind program in the Chinese context. A larger trial with longer follow-up period is suggested to better examine the effect of mindfulness on adolescents with ASD and their parents.

A Live Video Mind-Body Treatment to Prevent Persistent Symptoms Following Mild Traumatic Brain Injury: Protocol for a Mixed Methods Study

Background

Every year, approximately 42 million people sustain a mild traumatic brain injury (mTBI, also known as concussion), with particularly high rates among college-aged individuals. A substantial proportion of these people (44%-64%) develop persistent symptoms that are challenging to treat, costly, and associated with significant disability. Anxiety has emerged as a risk factor for progression from acute to persistent mTBI symptoms.

Objective

This study aims to develop, adapt, and establish the feasibility of the Toolkit for Optimal Recovery after Concussions (TOR-C), an innovative mind-body program aimed at preventing persistent symptoms among young adults with mTBI and comorbid anxiety. Here, we describe the proposed study design, methodology, measurement, and treatment manuals.

Methods

In phase 1, we will conduct individual, live video qualitative interviews (up to n=20) with college-aged individuals with mTBI and comorbid anxiety to inform adaptation of the intervention and study procedures. In phase 2, an open pilot of the live video TOR-C (n=5) with exit interviews will be conducted to explore the initial feasibility, acceptability, and credibility of the program and to refine the study procedures. Phase 3 will involve conducting a feasibility randomized controlled trial (N=50) of the TOR-C versus a health education control (Health Enhancement for Concussions; HE-C), both delivered via live video, to establish feasibility of recruitment procedures (screening, eligibility, and enrollment) and data collection; feasibility, credibility, and acceptability of the live video TOR-C and HE-C (adherence, retention, fidelity, and satisfaction) following prespecified benchmarks; and a signal of improvement in outcomes.

Results

Phase 1 of the study has been approved by the Massachusetts General Hospital Institutional Review Board. Study completion is anticipated by early 2025.

Conclusions

We will develop and test the first mind-body intervention focused on prevention of persistent symptoms following mTBI in young adults with comorbid anxiety problems. This will allow us to establish feasibility markers in postconcussive symptoms, anxiety, disability, and fear avoidance to inform a future efficacy trial of the TOR-C versus HE-C.

International Registered Report Identifier (IRRID)

PRR1-10.2196/25746

Self-care Strategies to Combat Burnout Among Pediatric Critical Care Nurses and Physicians

BACKGROUND

Professional burnout is a widespread phenomenon in health care. The health of patients and organizations begins with the well-being of health care professionals. Identifying and understanding self-care strategies that professionals perceive to be helpful is crucial to combat burnout.

OBJECTIVE

To determine perceptions of self-care strategies to combat professional burnout among nurses and physicians in pediatric critical care settings.

METHODS

This was a qualitative descriptive study with a phenomenological overtone. The study was conducted in a 20-bed pediatric intensive care unit and an 8-bed intermediate care unit of a children's hospital in the United States. Information flyers and emails were used to introduce the study. A combination of convenience and purposive sampling methods was used to recruit participants who were full-time nurses and physicians in the 2 units. Information saturation was used to regulate sample sizes, resulting in 20 participants. Data were collected through a onetime face-to-face interview with each participant. A qualitative descriptive approach was used to analyze the data. The first author was the primary coder and discussed the codes with the coauthors throughout the coding process.

RESULTS

Six major self-care strategies were identified: finding meaning in work, connecting with an energy source, nurturing interpersonal connections, developing an attitude of positivity, performing emotional hygiene, and recognizing one's uniqueness and contributions at work.

CONCLUSIONS

Developing effective self-care strategies helps promote health care professionals' physical and psychological well-being and reduce burnout. It is vital for health care professionals to care for themselves so that they can best care for others.

A unitary caring science resilience-building model: Unifying the human caring theory and research-informed psychology and neuroscience evidence

Resilience is the psychological capability to recover from difficulties quickly. Healthcare professionals are especially vulnerable to job-related stress and burnout. Unitary Caring Science is the framework for Watson's Human Caring Theory, providing a philosophy of practice in healthcare. With the high rates of clinician burnout and psychological issues, it will be significant to unify the human caring theory with research-informed psychological and neuroscience evidence to develop clinicians' resilience-building strategies. The purpose of this article is to introduce a Unitary Caring Science Resilience Model and explain the science behind the core strategies based on Unitary Caring Science philosophy and the psychological and neuroscience research. This model includes six strategies: Embracing loving-kindness for self and others; Nurturing interpersonal and intersubjective connections/relations; Deepening a creative use of self and sense of belonging; Balancing self-learning, self-awareness, and an evolved self-consciousness; Valuing forgiveness and releasing negativity; Inspiring and maintaining faith-hope. The caring-theory guided resilience-building strategies are proven to alleviate the depletion of clinicians' energy and emotions. Healthcare practices are challenging but rewarding. Clinicians can be emotionally, psychologically, and physically exhausted if they always consider themselves 'giving' and 'doing' institutional tasks without a sense of purpose or fulfillment. The practice can be rewarding if it becomes more aligned with clinicians' value to serve humanity. Through the unitary caring science resilience strategies, clinicians can build resilience as an antidote to clinician burnout and depletion.

Brief Mindfulness Meditation Induces Gray Matter Changes in a Brain Hub

Previous studies suggest that the practice of long-term (months to years) mindfulness meditation induces structural plasticity in gray matter. However, it remains unknown whether short-term (<30 days) mindfulness meditation in novices could induce similar structural changes. Our previous randomized controlled trials (RCTs) identified white matter changes surrounding the anterior cingulate cortex (ACC) and the posterior cingulate cortex (PCC) within 2 to 4 weeks, following 5-10 h of mindfulness training. Furthermore, these changes were correlated with emotional states in healthy adults. The PCC is a key hub in the functional anatomy implicated in meditation and other perspectival processes. In this longitudinal study using a randomized design, we therefore examined the effect of a 10 h of mindfulness training, the Integrative Body-Mind Training (IBMT) on gray matter volume of the PCC compared to an active control-relaxation training (RT). We found that brief IBMT increased ventral PCC volume and that baseline temperamental trait-an index of individual differences was associated with a reduction in training-induced gray matter increases. Our findings indicate that brief mindfulness meditation induces gray matter plasticity, suggesting that structural changes in ventral PCC-a key hub associated with self-awareness, emotion, cognition, and aging-may have important implications for protecting against mood-related disorders and aging-related cognitive declines.

Hippocampal circuits underlie improvements in self-reported anxiety following mindfulness training

INTRODUCTION

Mindfulness meditation has successfully been applied to cultivate skills in self-regulation of emotion, as it employs the unbiased present moment awareness of experience. This heightened attention to and awareness of sensory experience has been postulated to create an optimal therapeutic exposure condition and thereby improve extinction learning. We recently demonstrated increased connectivity in hippocampal circuits during the contextual retrieval of extinction memory following mindfulness training.

METHODS

Here, we examine the role of structural changes in hippocampal subfields following mindfulness training in a randomized controlled longitudinal study using a two-day fear-conditioning and extinction protocol.

RESULTS

We demonstrate an association between mindfulness training-related increases in subiculum and decreased hippocampal connectivity to lateral occipital regions during contextual retrieval of extinguished fear. Further, we demonstrate an association between decreased connectivity and decreases in self-reported anxiety following mindfulness training.

CONCLUSIONS

The results highlight the role of the subiculum in gating interactions with contextual stimuli during memory retrieval and, also, the mechanisms through which mindfulness training may foster resilience.

[The Effect of a Short-Term Mindfulness Program on Memory Performance in School-Aged Children]

The Effect of a Short-Term Mindfulness Program on Memory Performance in School-Aged Children A one-week mindfulness-based intervention designed to improve 8- to 10-year-old children's memory performance was investigated. Seventy-three children were quasi-randomly assigned either to one of two mindfulness-based intervention groups (breathing meditation or yoga), or to an active control group. The sessions were held on six consecutive days. Prior to intervention and after completing the intervention, children's short-term and long-term memory performance were assessed. In confirmation of prior studies, breathing meditation and yoga showed positive effects on memory performance when compared with the control group. Moreover, differences in the effectiveness of breathing meditation and yoga were found: While both interventions had comparable effects on long-term memory, only breathing meditation showed improvements in short-term memory performance. The present study provides valuable evidence on the effectiveness of meditation on cognitive functions in childhood and shows that school-aged children can already benefit from short-term meditation programs.

[School-based Mindfulness Programs for Children and Adolescents]

School-based Mindfulness Programs for Children and Adolescents Mindfulness is a mental state achieved by focusing one's awareness on the present moment, while calmly acknowledging and accepting one's bodily sensations, sensory feedback, thoughts, and feelings. Mindfulness interventions can improve proprioception, direction of attention, and emotion regulation. An accepting attitude towards thoughts and feelings reduces the experience of stress so that it is easier to cope with stressful situations. The regular practice of mindfulness exercises affects neurobiological mechanisms, which can lead to an improvement of executive functions as well as psychological health. Metaanalyses provide evidence of small effects of mindfulness interventions in schools, both in cognitive areas (executive functions, concentration, memory) and in emotional areas (anxiety, depressivity, wellbeing). The focus of this review article is on German and English-language mindfulness programmes for children and adolescents in schools, which have already been the subject of initial evaluation studies. This study presents the programmes Paws b, Mind Up, and Mehr Ruhe for children, and .b, Mind Up, AISCHU, and 8sam for adolescents, together with their evaluation results. The conclusion discusses open questions concerning conceptual and methodological issues.

Brain network topology predicts participant adherence to mental training programs

Adherence determines the success and benefits of mental training (e.g., meditation) programs. It is unclear why some participants engage more actively in programs for mental training than others. Understanding neurobiological factors that predict adherence is necessary for understanding elements of learning and to inform better designs for new learning regimens. Clustering patterns in brain networks have been suggested to predict learning performance, but it is unclear whether these patterns contribute to motivational aspects of learning such as adherence. This study tests whether configurations of brain connections in resting-state fMRI scans can be used to predict adherence to two programs: meditation and creative writing. Results indicate that greater system segregation and clustering predict the number of practice sessions and class participation in both programs at a wide range of network thresholds (corrected p value < 0.05). At a local level, regions in subcortical circuitry such as striatum and accumbens predicted adherence in all subjects. Furthermore, there were also some important distinctions between groups: Adherence to meditation was predicted by connectivity within local network of the anterior insula and default mode network; and in the writing program, adherence was predicted by network neighborhood of frontal and temporal regions. Four machine learning methods were applied to test the robustness of the brain metric for classifying individual capacity for adherence and yielded reasonable accuracy. Overall, these findings underscore the fact that adherence and the ability to perform prescribed exercises is associated with organizational patterns of brain connectivity.

Effects of short-term mindfulness-based training on executive function: Divergent but promising

Mindfulness-based training (MBT) has repeatedly been proven effective in improving mental health, as well as in eliciting advantages in executive functions (EFs), as demonstrated by objective measures. However, few studies have discussed the role MBT plays in increasing EFs over short periods of time. This current review, to our knowledge, is the first study to investigate the effect of short-term MBT on EFs. In this case, 14 studies were eventually included after literature screening using PubMed, MEDLINE, Elsevier, Embase, EBSCO and references from retrieved articles. We found that the relationship between short-term MBT and three main components of EFs were found controversial. Some reported that individuals' inhibition, working memory and attention shifting were significantly improved by short-term MBT, whereas others reported no such strong connections between MBT and EFs. These controversial findings result from the use of varied assessment instruments, cognitive tasks and experimental materials. Nonetheless, the findings from this review suggest short-term MBT could be of great value in improving mental health, which might especially enable the enhancement of individuals' inhibition and updating subfunctions of EFs. These practical evidences could have a strong impact on clinical psychology. However, the lack of consistency across the studies in this review indicated that more standardized and profound studies exploring the effects of short-term MBT on EFs are needed in the future.

Strengthened Hippocampal Circuits Underlie Enhanced Retrieval of Extinguished Fear Memories Following Mindfulness Training

BACKGROUND

The role of hippocampus in context-dependent recall of extinction is well recognized. However, little is known about how intervention-induced changes in hippocampal networks relate to improvements in extinction learning. In this study, we hypothesized that mindfulness training creates an optimal exposure condition by heightening attention and awareness of present moment sensory experience, leading to enhanced extinction learning, improved emotion regulation, and reduced anxiety symptoms.

METHODS

We tested this hypothesis in a randomized controlled longitudinal study design using a 2-day fear conditioning and extinction protocol. The mindfulness training group included 42 participants (28 women) and the control group included 25 participants (15 women).

RESULTS

We show that mindfulness training is associated with differential engagement of the right supramarginal gyrus as well as hippocampal-cortical reorganization. We also report enhanced hippocampal connectivity to the primary sensory cortex during retrieval of extinguished stimuli following mindfulness training.

CONCLUSIONS

These findings suggest hippocampal-dependent changes in contextual retrieval as one plausible neural mechanism through which mindfulness-based interventions enhance fear extinction and foster stress resilience.

A neurobehavioral account for decentering as the salve for the distressed mind

Distress is commonly characterized by prolonged internal suffering that can range from self-focused processing of negative emotions and stressors, to highly intensely aversive and prolonged emotional states, thereby, worsening or complicating emotional and physical conditions. Decentering represents a metacognitive capacity thought to reflect three interrelated processes: meta-awareness, disidentification from internal experience, and reduced reactivity to thought content-which is reliably increased with mindfulness-based interventions. In this essay, we seek to link the clinical presentation of distress disorders to known or hypothesized disruptions in neural networks that underlie emotion, cognition, and goal directed behavior, and offer a neurobehavioral account for how and why treatments imbued with mindfulness meditation might ameliorate these conditions, in part through increases in decentering.