Resting state functional connectivity changes following mindfulness-based stress reduction predict improvements in disease control for patients with asthma.

BACKGROUND: The staggering morbidity associated with chronic inflammatory diseases can be reduced by psychological interventions, including Mindfulness-Based Stress Reduction (MBSR). Proposed mechanisms for MBSR's beneficial effects include changes in salience network function. Salience network perturbations are also associated with chronic inflammation, including airway inflammation in asthma, a chronic inflammatory disease affecting approximately 10% of the population. However, no studies have examined whether MBSR-related improvements in disease control are related to changes in salience network function. METHODS: Adults with asthma were randomized to 8 weeks of MBSR or a waitlist control group. Resting state functional connectivity was measured using fMRI before randomization, immediately post-intervention, and 4 months post-intervention. Using key salience network regions as seeds, we calculated group differences in change in functional connectivity over time and examined whether functional connectivity changes were associated with increased mindfulness, improved asthma control, and decreased inflammatory biomarkers. RESULTS: The MBSR group showed greater increases in functional connectivity between salience network regions relative to the waitlist group. Improvements in asthma control correlated with increased functional connectivity between the salience network and regions important for attention control and emotion regulation. Improvements in inflammatory biomarkers were related to decreased functional connectivity between the salience network and other networks. CONCLUSIONS: Increased resting salience network coherence and connectivity with networks that subserve attention and emotion regulation may contribute to the benefits of MBSR for patients with asthma. Understanding the neural underpinnings of MBSR-related benefits in patients is a critical step towards optimizing brain-targeted interventions for chronic inflammatory disease management.

Slower respiration rate is associated with higher self-reported well-being after wellness training.

Mind-body interventions such as mindfulness-based stress reduction (MBSR) may improve well-being by increasing awareness and regulation of physiological and cognitive states. However, it is unclear how practice may alter long-term, baseline physiological processes, and whether these changes reflect improved well-being. Using respiration rate (RR), which can be sensitive to effects of meditation, and 3 aspects of self-reported well-being (psychological well-being [PWB], distress, and medical symptoms), we tested pre-registered hypotheses that: (1) Lower baseline RR (in a resting, non-meditative state) would be a physiological marker associated with well-being, (2) MBSR would decrease RR, and (3) Training-related decreases in RR would be associated with improved well-being. We recruited 245 adults (age range = 18-65, M = 42.4): experienced meditators (n = 42), and meditation-naïve participants randomized to MBSR (n = 72), active control (n = 41), or waitlist control (n = 66). Data were collected at pre-randomization, post-intervention (or waiting), and long-term follow-up. Lower baseline RR was associated with lower psychological distress among long-term meditators (p* = 0.03, b = 0.02, 95% CI [0.01, 0.03]), though not in non-meditators prior to training. MBSR decreased RR compared to waitlist (p = 0.02, Cohen's d = - 0.41, 95% CI [- 0.78, - 0.06]), but not the active control. Decreased RR related to decreased medical symptoms, across all participants (p* = 0.02, b = 0.57, 95% CI [0.15, 0.98]). Post-training, lower RR was associated with higher PWB across training groups compared to waitlist (p* = 0.01, b = 0.06, 95% CI [0.02, 0.10]), though there were no significant differences in change in PWB between groups. This physiological marker may indicate higher physical and/or psychological well-being in those who engage in wellness practices.

Neural Signatures of Pain Modulation in Short-Term and Long-Term Mindfulness Training: A Randomized Active-Control Trial.

OBJECTIVE: Mindfulness-based interventions are widely used to target pain, yet their neural mechanisms of action are insufficiently understood. The authors studied neural and subjective pain response in a randomized active-control trial of mindfulness-based stress reduction (MBSR) alongside long-term meditation practitioners. METHODS: Healthy participants (N=115) underwent functional neuroimaging during a thermal acute pain task before and after random assignment to MBSR (N=28), an active control condition (health enhancement program [HEP]) (N=32), or a waiting list control condition (N=31). Long-term meditators (N=30) completed the same neuroimaging paradigm. Pain response was measured via self-reported intensity and unpleasantness, and neurally via two multivoxel machine-learning-derived signatures: the neurologic pain signature (NPS), emphasizing nociceptive pain processing, and the stimulus intensity independent pain signature-1 (SIIPS1), emphasizing stimulus-independent neuromodulatory processes. RESULTS: The MBSR group showed a significant decrease in NPS response relative to the HEP group (Cohen's d=-0.43) and from pre- to postintervention assessment (d=-0.47). The MBSR group showed small, marginal decreases in NPS relative to the waiting list group (d=-0.36), and in SIIPS1 relative to both groups (HEP group, d=-0.37; waiting list group, d=-0.37). In subjective unpleasantness, the MBSR and HEP groups also showed modest significant reductions compared with the waiting list group (d=-0.45 and d=-0.55). Long-term meditators reported significantly lower pain than nonmeditators but did not differ in neural response. Within the long-term meditator group, cumulative practice during intensive retreat was significantly associated with reduced SIIPS1 (r=-0.65), whereas daily practice was not. CONCLUSIONS: Mindfulness training showed associations with pain reduction that implicate differing neural pathways depending on extent and context of practice. Use of neural pain signatures in randomized trials offers promise for guiding the application of mindfulness interventions to pain treatment.

Long-term Meditation Training Is Associated with Enhanced Subjective Attention and Stronger Posterior Cingulate-Rostrolateral Prefrontal Cortex Resting Connectivity.

Mindfulness meditation has been shown to increase resting-state functional connectivity (rsFC) between the posterior cingulate cortex (PCC) and dorsolateral prefrontal cortex (DLPFC), which is thought to reflect improvements in shifting attention to the present moment. However, prior research in long-term meditation practitioners lacked quantitative measures of attention that would provide a more direct behavioral correlate and interpretational anchor for PCC-DLPFC connectivity and was inherently limited by small sample sizes. Moreover, whether mindfulness meditation primarily impacts brain function locally, or impacts the dynamics of large-scale brain networks, remained unclear. Here, we sought to replicate and extend prior findings of increased PCC-DLPFC rsFC in a sample of 40 long-term meditators (average practice = 3759 hr) who also completed a behavioral assay of attention. In addition, we tested a network-based framework of changes in interregional connectivity by examining network-level connectivity. We found that meditators had stronger PCC-rostrolateral prefrontal cortex (RLPFC) rsFC, lower connector hub strength across the default mode network, and better subjective attention, compared with 124 meditation-naive controls. Orienting attention positively correlated with PCC-RLPFC connectivity and negatively correlated with default mode network connector hub strength. These findings provide novel evidence that PCC-RLPFC rsFC may support attention orienting, consistent with a role for RLPFC in the attention shifting component of metacognitive awareness that is a core component of mindfulness meditation training. Our results further demonstrate that long-term mindfulness meditation may improve attention and strengthen the underlying brain networks.

Absence of structural brain changes from mindfulness-based stress reduction: Two combined randomized controlled trials.

Studies purporting to show changes in brain structure following the popular, 8-week mindfulness-based stress reduction (MBSR) course are widely referenced despite major methodological limitations. Here, we present findings from a large, combined dataset of two, three-arm randomized controlled trials with active and waitlist (WL) control groups. Meditation-naïve participants (n = 218) completed structural magnetic resonance imaging scans during two visits: baseline and postintervention period. After baseline, participants were randomly assigned to WL (n = 70), an 8-week MBSR program (n = 75), or a validated, matched active control (n = 73). We assessed changes in gray matter volume, gray matter density, and cortical thickness. In the largest and most rigorously controlled study to date, we failed to replicate prior findings and found no evidence that MBSR produced neuroplastic changes compared to either control group, either at the whole-brain level or in regions of interest drawn from prior MBSR studies.

Mindfulness video game improves connectivity of the fronto-parietal attentional network in adolescents: A multi-modal imaging study.

Mindfulness training has been shown to improve attention and change the underlying brain substrates in adults. Most mindfulness training programs involve a myriad of techniques, and it is difficult to attribute changes to any particular aspect of the program. Here, we created a video game, Tenacity, which models a specific mindfulness technique - focused attention on one's breathing - and assessed its potential to train an attentional network in adolescents. A combined analysis of resting state functional connectivity (rs-FC) and diffusion tensor imaging (DTI) yielded convergent results - change in communication within the left fronto-parietal network after two weeks of playing Tenacity compared to a control game. Rs-FC analysis showed greater connectivity between left dorsolateral prefrontal cortex (dlPFC) and left inferior parietal cortex (IPC) in the Tenacity group. Importantly, changes in left dlPFC - IPC rs-FC and changes in structural connectivity of the white matter tract that connects these regions -left superior longitudinal fasiculus (SLF) - were associated with changes in performance on an attention task. Finally, changes in left dlPFC - IPC rs-FC correlated with the change in left SLF structural connectivity as measured by fractional anisotropy (FA) in the Tenacity group only.

The Effect of Mindfulness Meditation on Impulsivity and its Neurobiological Correlates in Healthy Adults.

Interest has grown in using mindfulness meditation to treat conditions featuring excessive impulsivity. However, while prior studies find that mindfulness practice can improve attention, it remains unclear whether it improves other cognitive faculties whose deficiency can contribute to impulsivity. Here, an eight-week mindfulness intervention did not reduce impulsivity on the go/no-go task or Barratt Impulsiveness Scale (BIS-11), nor produce changes in neural correlates of impulsivity (i.e. frontostriatal gray matter, functional connectivity, and dopamine levels) compared to active or wait-list control groups. Separately, long-term meditators (LTMs) did not perform differently than meditation-naïve participants (MNPs) on the go/no-go task. However, LTMs self-reported lower attentional impulsivity, but higher motor and non-planning impulsivity on the BIS-11 than MNPs. LTMs had less striatal gray matter, greater cortico-striatal-thalamic functional connectivity, and lower spontaneous eye-blink rate (a physiological dopamine indicator) than MNPs. LTM total lifetime practice hours (TLPH) did not significantly relate to impulsivity or neurobiological metrics. Findings suggest that neither short- nor long-term mindfulness practice may be effective for redressing impulsive behavior derived from inhibitory motor control or planning capacity deficits in healthy adults. Given the absence of TLPH relationships to impulsivity or neurobiological metrics, differences between LTMs and MNPs may be attributable to pre-existing differences.

Mindfulness-Based Stress Reduction-related changes in posterior cingulate resting brain connectivity.

Mindfulness meditation training has been shown to increase resting-state functional connectivity between nodes of the frontoparietal executive control network (dorsolateral prefrontal cortex [DLPFC]) and the default mode network (posterior cingulate cortex [PCC]). We investigated whether these effects generalized to a Mindfulness-Based Stress Reduction (MBSR) course and tested for structural and behaviorally relevant consequences of change in connectivity. Healthy, meditation-naïve adults were randomized to either MBSR (N = 48), an active (N = 47) or waitlist (N = 45) control group. Participants completed behavioral testing, resting-state fMRI scans and diffusion tensor scans at pre-randomization (T1), post-intervention (T2) and ~5.5 months later (T3). We found increased T2-T1 PCC-DLPFC resting connectivity for MBSR relative to control groups. Although these effects did not persist through long-term follow-up (T3-T1), MBSR participants showed a significantly stronger relationship between days of practice (T1 to T3) and increased PCC-DLPFC resting connectivity than participants in the active control group. Increased PCC-DLPFC resting connectivity in MBSR participants was associated with increased microstructural connectivity of a white matter tract connecting these regions and increased self-reported attention. These data show that MBSR increases PCC-DLPFC resting connectivity, which is related to increased practice time, attention and structural connectivity.

Mindfulness Meditation and Psychopathology.

Mindfulness meditation is increasingly incorporated into mental health interventions, and theoretical concepts associated with it have influenced basic research on psychopathology. Here, we review the current understanding of mindfulness meditation through the lens of clinical neuroscience, outlining the core capacities targeted by mindfulness meditation and mapping them onto cognitive and affective constructs of the Research Domain Criteria matrix proposed by the National Institute of Mental Health. We review efficacious applications of mindfulness meditation to specific domains of psychopathology including depression, anxiety, chronic pain, and substance abuse, as well as emerging efforts related to attention disorders, traumatic stress, dysregulated eating, and serious mental illness. Priorities for future research include pinpointing mechanisms, refining methodology, and improving implementation. Mindfulness meditation is a promising basis for interventions, with particular potential relevance to psychiatric comorbidity. The successes and challenges of mindfulness meditation research are instructive for broader interactions between contemplative traditions and clinical psychological science.

Impact of short- and long-term mindfulness meditation training on amygdala reactivity to emotional stimuli.

Meditation training can improve mood and emotion regulation, yet the neural mechanisms of these affective changes have yet to be fully elucidated. We evaluated the impact of long- and short-term mindfulness meditation training on the amygdala response to emotional pictures in a healthy, non-clinical population of adults using blood-oxygen level dependent functional magnetic resonance imaging. Long-term meditators (N = 30, 16 female) had 9081 h of lifetime practice on average, primarily in mindfulness meditation. Short-term training consisted of an 8-week Mindfulness- Based Stress Reduction course (N = 32, 22 female), which was compared to an active control condition (N = 35, 19 female) in a randomized controlled trial. Meditation training was associated with less amygdala reactivity to positive pictures relative to controls, but there were no group differences in response to negative pictures. Reductions in reactivity to negative stimuli may require more practice experience or concentrated practice, as hours of retreat practice in long-term meditators was associated with lower amygdala reactivity to negative pictures - yet we did not see this relationship for practice time with MBSR. Short-term training, compared to the control intervention, also led to increased functional connectivity between the amygdala and a region implicated in emotion regulation - ventromedial prefrontal cortex (VMPFC) - during affective pictures. Thus, meditation training may improve affective responding through reduced amygdala reactivity, and heightened amygdala-VMPFC connectivity during affective stimuli may reflect a potential mechanism by which MBSR exerts salutary effects on emotion regulation ability.