Neural correlates of mindfulness meditation-related anxiety relief.
ABSTRACT: Anxiety is the cognitive state related to the inability to control emotional responses to perceived threats. Anxiety is inversely related to brain activity associated with the cognitive regulation of emotions. Mindfulness meditation has been found to regulate anxiety. However, the brain mechanisms involved in meditation-related anxiety relief are largely unknown. We employed pulsed arterial spin labeling MRI to compare the effects of distraction in the form of attending to the breath (ATB; before meditation training) to mindfulness meditation (after meditation training) on state anxiety across the same subjects. Fifteen healthy subjects, with no prior meditation experience, participated in 4 d of mindfulness meditation training. ATB did not reduce state anxiety, but state anxiety was significantly reduced in every session that subjects meditated. Meditation-related anxiety relief was associated with activation of the anterior cingulate cortex, ventromedial prefrontal cortex and anterior insula. Meditation-related activation in these regions exhibited a strong relationship to anxiety relief when compared to ATB. During meditation, those who exhibited greater default-related activity (i.e. posterior cingulate cortex) reported greater anxiety, possibly reflecting an inability to control self-referential thoughts. These findings provide evidence that mindfulness meditation attenuates anxiety through mechanisms involved in the regulation of self-referential thought processes.
Project description:Recent studies indicate that mindfulness meditation training interventions reduce stress and improve stress-related health outcomes, but the neural pathways for these effects are unknown. The present research evaluates whether mindfulness meditation training alters resting state functional connectivity (rsFC) of the amygdala, a region known to coordinate stress processing and physiological stress responses. We show in an initial discovery study that higher perceived stress over the past month is associated with greater bilateral amygdala-subgenual anterior cingulate cortex (sgACC) rsFC in a sample of community adults (n?=?130). A follow-up, single-blind randomized controlled trial shows that a 3-day intensive mindfulness meditation training intervention (relative to a well-matched 3-day relaxation training intervention without a mindfulness component) reduced right amygdala-sgACC rsFC in a sample of stressed unemployed community adults (n?=?35). Although stress may increase amygdala-sgACC rsFC, brief training in mindfulness meditation could reverse these effects. This work provides an initial indication that mindfulness meditation training promotes functional neuroplastic changes, suggesting an amygdala-sgACC pathway for stress reduction effects.
Project description:Increasing neuroimaging evidence suggests that mindfulness meditation expertise is related to different functional and structural configurations of the default mode network (DMN), the salience network (SN) and the executive network at rest. However, longitudinal studies observing resting network plasticity effects in brains of novices who started to practice meditation are scarce and generally related to one dimension, such as structural or functional effects. The purpose of this study was to investigate structural and functional brain network changes (e.g. DMN) after 40 days of mindfulness meditation training in novices and set these in the context of potentially altered depression symptomatology and anxiety. We found overlapping structural and functional effects in precuneus, a posterior DMN region, where cortical thickness increased and low-frequency amplitudes (ALFF) decreased, while decreased ALFF in left precuneus/posterior cingulate cortex correlates with the reduction of (CES-D) depression scores. In conclusion, regional overlapping of structural and functional changes in precuneus may capture different components of the complex changes of mindfulness meditation training.
Project description:Mindfulness meditation training has been previously shown to enhance behavioral measures of executive control (e.g., attention, working memory, cognitive control), but the neural mechanisms underlying these improvements are largely unknown. Here, we test whether mindfulness training interventions foster executive control by strengthening functional connections between dorsolateral prefrontal cortex (dlPFC)-a hub of the executive control network-and frontoparietal regions that coordinate executive function.Thirty-five adults with elevated levels of psychological distress participated in a 3-day randomized controlled trial of intensive mindfulness meditation or relaxation training. Participants completed a resting state functional magnetic resonance imaging scan before and after the intervention. We tested whether mindfulness meditation training increased resting state functional connectivity (rsFC) between dlPFC and frontoparietal control network regions.Left dlPFC showed increased connectivity to the right inferior frontal gyrus (T = 3.74), right middle frontal gyrus (MFG) (T = 3.98), right supplementary eye field (T = 4.29), right parietal cortex (T = 4.44), and left middle temporal gyrus (T = 3.97, all p < .05) after mindfulness training relative to the relaxation control. Right dlPFC showed increased connectivity to right MFG (T = 4.97, p < .05).We report that mindfulness training increases rsFC between dlPFC and dorsal network (superior parietal lobule, supplementary eye field, MFG) and ventral network (right IFG, middle temporal/angular gyrus) regions. These findings extend previous work showing increased functional connectivity among brain regions associated with executive function during active meditation by identifying specific neural circuits in which rsFC is enhanced by a mindfulness intervention in individuals with high levels of psychological distress.Clinicaltrials.gov,NCT01628809.
Project description:Mindfulness meditation is a self-regulatory practice premised on sustaining nonreactive awareness of arising sensory events that reliably reduces pain. Yet, the specific analgesic mechanisms supporting mindfulness have not been comprehensively disentangled from the potential nonspecific factors supporting this technique. Increased parasympathetic nervous system (PNS) activity is associated with pain relief corresponding to a number of cognitive manipulations. However, the relationship between the PNS and mindfulness-based pain attenuation remains unknown. The primary objective of the present study was to determine the role of high-frequency heart rate variability (HF HRV), a marker of PNS activity, during mindfulness-based pain relief as compared to a validated, sham-mindfulness meditation technique that served as a breathing-based control. Sixty-two healthy volunteers (31 females; 31 males) were randomized to a 4-session (25 min/session) mindfulness or sham-mindfulness training regimen. Before and after each group's respective training, participants were administered noxious (49°C) and innocuous (35°C) heat to the right calf. HF HRV and respiration rate were recorded during thermal stimulation and pain intensity and unpleasantness ratings were collected after each stimulation series. The primary analysis revealed that during mindfulness meditation, higher HF HRV was more strongly associated with lower pain unpleasantness ratings when compared to sham-mindfulness meditation (B?=?-.82, P = .04). This finding is in line with the prediction that mindfulness-based meditation engages distinct mechanisms from sham-mindfulness meditation to reduce pain. However, the same prediction was not confirmed for pain intensity ratings (B?=?-.41). Secondary analyses determined that mindfulness and sham-mindfulness meditation similarly reduced pain ratings, decreased respiration rate, and increased HF HRV (between group ps < .05). More mechanistic work is needed to reliably determine the role of parasympathetic activation in mindfulness-based pain relief as compared to other meditative techniques. Perspective: Mindfulness has been shown to engage multiple mechanisms to reduce pain. The present study extends on this work to show that higher HRV is associated with mindfulness-induced reductions in pain unpleasantness, but not pain intensity ratings, when compared to sham-mindfulness meditation. These findings warrant further investigation into the mechanisms engaged by mindfulness as compared to placebo.
Project description:Objectives:Previous research indicates that mindfulness meditation reduces anxiety and depression and enhances well-being. We examined the impact of app-delivered mindfulness meditation on resting state functional MRI (fMRI) connectivity among physician assistant (PA) students and surgery residents. Methods:PA students and residents were randomized to receive a popular meditation app or to wait-list control group. Before and after the 8-week meditation period, we acquired fMRI scans of participants' resting state, and participants completed a self-report measure of mindfulness. We used a 2?×?2, within- and between-group factorial design and leveraged a whole-brain connectome approach to examine changes in within- and between-network connectivity across the entire brain, and to examine whether changes in connectivity were associated with app use or to changes in self-reported mindfulness. Results:Meditation practitioners exhibited significantly stronger connectivity between the frontoparietal network and the left and right nucleus accumbens and between the default mode (DMN) and salience networks, among other regions. Mindfulness practice time was correlated with increased connectivity between the lateral parietal cortex and the supramarginal gyrus, which were also positively correlated with increased scores on the "Describing" subscale of the Five Facet Mindfulness Questionnaire between baseline and post-meditation. These findings are consistent with previous research indicating that mindfulness-based interventions alter functional connectivity within the DMN and between the DMN and other networks both during meditation and at rest, as well as increased connectivity in systems important for emotion and reward. Conclusions:Recent commentaries call for healthcare provider and trainee wellness programs that are sustainable and preventive in nature rather than reactive; these data indicate that even brief sessions of app-delivered mindfulness practice are associated with functional connectivity changes in a dose-dependent manner.
Project description:Experienced meditators are able to voluntarily modulate their state of consciousness and attention. In the present study, we took advantage of this ability and studied brain activity related to the shift of mental state. Electrophysiological activity, i.e. EEG, was recorded from 11 subjects with varying degrees of meditation experience during Zen meditation (a form of open monitoring meditation) and during non-meditation rest. On a behavioral level, mindfulness scores were assessed using the Mindfulness Attention and Awareness Scale (MAAS). Analysis of EEG source power revealed the so far unreported finding that MAAS scores significantly correlated with gamma power (30-250Hz), particularly high-frequency gamma (100-245Hz), during meditation. High levels of mindfulness were related to increased high-frequency gamma, for example, in the cingulate cortex and somatosensory cortices. Further, we analyzed the relationship between connectivity during meditation and self-reported mindfulness (MAAS). We found a correlation between graph measures in the 160-170Hz range and MAAS scores. Higher levels of mindfulness were related to lower small worldedness as well as global and local clustering in paracentral, insular, and thalamic regions during meditation. In sum, the present study shows significant relationships of mindfulness and brain activity during meditation indicated by measures of oscillatory power and graph theoretical measures. The most prominent effects occur in brain structures crucially involved in processes of awareness and attention, which also show structural changes in short- and long-term meditators, suggesting continuative alterations in the meditating brain. Overall, our study reveals strong changes in ongoing oscillatory activity as well as connectivity patterns that appear to be sensitive to the psychological state changes induced by Zen meditation.
Project description:Evidence indicates meditation facilitates affective regulation and reduces negative affect. It also influences resting-state functional connectivity between affective networks and the posterior cingulate (PCC)/precuneus, regions critically implicated in self-referential processing. However, no longitudinal study employing active control group has examined the effect of meditation training on affective processing, PCC/precuneus connectivity, and their association. Here, we report that eight-week meditation, but not relaxation, training 'neutralized' affective processing of positive and negative stimuli in healthy elderly participants. Additionally, meditation versus relaxation training increased the positive connectivity between the PCC/precuneus and the pons, the direction of which was largely directed from the pons to the PCC/precuneus, as revealed by dynamic causal modeling. Further, changes in connectivity between the PCC/precuneus and pons predicted changes in affective processing after meditation training. These findings indicate meditation promotes self-referential affective regulation based on increased regulatory influence of the pons on PCC/precuneus, which new affective-processing strategy is employed across both resting state and when evaluating affective stimuli. Such insights have clinical implications on interventions on elderly individuals with affective disorders.
Project description:<h4>Background</h4>Psychological distress in University settings has grown and became a public health concern. In this context, contemplative practices such as mindfulness have been proposed as a strategy to help students on stress management.<h4>Methods</h4>Forty university students (20 female), aged between 18 to 30 years (mean?=?24.15; SD?=?3.56), with no previous experience with meditation or yoga were recruited at the Federal University of Rio Grande do Norte and randomized to a mindfulness training (MT) or active control (AC) groups. We analyzed measures of anxiety, affect, stress, as well as state and trait mindfulness in order to evaluate the effects of trait mindfulness and a brief mindfulness intervention in forty healthy young students. Participants were classified as Low (n?=?27, females?=?13) or High (n?=?13, females?=?7) Trait Mindfulness by k-means clustering and compared between them using Wilcoxon sum rank test. Furthermore, the sample was randomly allocated to an AC (n?=?20, females?=?10) or a MT (n?=?20, females?=?10) group, and mixed analysis of variance was performed to analyze the effect of interventions. The mechanisms and role of trait mindfulness in the intervention was assessed by a moderated mediation analysis.<h4>Results</h4>We found that High Trait individuals have lower anxiety trait, anxiety state and perceived stress levels. Only the MT group reduced their anxiety state and perceived stress after the intervention and increased their state mindfulness. Both groups reduced negative affect and cortisol, and no change was found in positive affect. Moderated mediation analysis showed that the training-induced change in state mindfulness mediated the increase in positive affect and the decrease in perceived stress and cortisol, regardless of trait mindfulness. For anxiety state the decrease only occurred in individuals with High Trait Mindfulness.<h4>Conclusions</h4>Together, these results suggest that higher trait mindfulness is associated with low levels of psychological distress and that a brief mindfulness-based intervention seems to be useful to reduce distress measures in university students.<h4>Trial registration</h4>ReBEC, U1111-1194-8661. Registered 28 March 2017-Retrospectively registered, http://www.ensaiosclinicos.gov.br/rg/RBR-7b8yh8.
Project description: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.
Project description:BACKGROUND:Effective transdiagnostic treatments for patients presenting with principal or comorbid symptoms of anxiety and depression enable more efficient provision of mental health care and may be particularly suitable for the varied population seen in primary healthcare settings. Mindfulness-integrated cognitive behavior therapy (MiCBT) is a transdiagnostic intervention that integrates aspects of CBT, including exposure skills targeting avoidance, with training in mindfulness meditation skills adopted from the Vipassana or insight tradition taught by the Burmese teachers U Ba Khin and Goenka. MiCBT is distinguished from both cognitive therapy and mindfulness-based cognitive therapy by the use of a theoretical framework which proposes that the locus of reinforcement of behavior is the interoceptive experience (body sensations) that co-arises with self-referential thinking. Consequently, MiCBT has a strong focus on body scanning to develop interoceptive awareness and equanimity. Designed for clinical purposes, the four-stage systemic approach of MiCBT, comprising intra-personal (Stage 1) exposure (Stage 2), interpersonal (Stage 3), and empathic (Stage 4) skillsets, is a distinguishing feature among other mindfulness-based interventions (MBIs). The aim of this study is to investigate whether and how group MiCBT decreases depression and anxiety symptoms for patients with a range of common mental health conditions. METHODS:Participants (n =?120) recruited via medical practitioner referral will be randomized to MiCBT or a wait-list control. Inclusion criteria are age 18-75; fluent in English and having a Kessler Psychological Distress Scale (K10) score of 20 or more. The MiCBT treatment group receive an 8-week MiCBT intervention delivered in a private psychology practice. Participants complete a suite of online self-report measures and record the amount of meditation practice undertaken each week. The control group receive usual treatment and complete the measures at the same time points. Primary outcome measures are the Depression Anxiety Stress Scale-21 (DASS-21) and K10. Analysis will use mixed-model repeated measures. DISCUSSION:The potential ability of MiCBT to provide a comprehensive therapeutic system that is applicable across diagnostic groups would make it an attractive addition to the available MBIs. TRIAL REGISTRATION:This trial is registered with the Australia and New Zealand Clinical Trials Registry: ACTRN12617000061336; Date of registration: 11th January 2017.