Does meditation training promote pro-environmental behavior? A cross-sectional comparison and a randomized controlled trial.

Meditation training may promote pro-environmental behavior and related variables, though limited research has tested this experimentally. We investigated whether short- or long-term meditation training were associated with pro-environmental behavior, environmental attitudes, and sustainable well-being (i.e., well-being per unit consumption). In a cross-sectional comparison, long-term meditators (n=31; mean=9,154 meditation hours) displayed greater environmental attitudes (d=0.63) but not pro-environmental behavior or sustainable well-being compared to meditation-naïve participants (ds=-0.14-0.27). In a randomized controlled trial (n=125), eight-week training in Mindfulness-Based Stress Reduction did not significantly improve target variables relative to waitlist or structurally-matched active control (ds=-0.38-0.43). However, relative to waitlist, randomization to either meditation or active control predicted increases in pro-environmental behavior (d=-0.40) and sustainable well-being (d=0.42), although the latter finding was not robust to multiple imputation. While meditation training may promote pro-environmental behavior and its antecedents, the training investigated here does not appear to be uniquely effective.

Reduced stress and inflammatory responsiveness in experienced meditators compared to a matched healthy control group.

Psychological stress is a major contributor to symptom exacerbation across many chronic inflammatory conditions and can acutely provoke increases in inflammation in healthy individuals. With the rise in rates of inflammation-related medical conditions, evidence for behavioral approaches that reduce stress reactivity is of value. Here, we compare 31 experienced meditators, with an average of approximately 9000 lifetime hours of meditation practice (M age=51years) to an age- and sex-matched control group (n=37; M age=48years) on measures of stress- and inflammatory responsivity, and measures of psychological health. The Trier Social Stress Test (TSST) was used to induce psychological stress and a neurogenic inflammatory response was produced using topical application of capsaicin cream to forearm skin. Size of the capsaicin-induced flare response and increase in salivary cortisol and alpha amylase were used to quantify the magnitude of inflammatory and stress responses, respectively. Results show that experienced meditators have lower TSST-evoked cortisol (62.62±2.52 vs. 70.38±2.33; p<.05) and perceived stress (4.18±.41 vs. 5.56±.30; p<.01), as well as a smaller neurogenic inflammatory response (81.55±4.6 vs. 96.76±4.26; p<.05), compared to the control group. Moreover, experienced meditators reported higher levels of psychological factors associated with wellbeing and resilience. These results suggest that the long-term practice of meditation may reduce stress reactivity and could be of therapeutic benefit in chronic inflammatory conditions characterized by neurogenic inflammation.

No sustained attention differences in a longitudinal randomized trial comparing mindfulness based stress reduction versus active control.

BACKGROUND: Mindfulness Based Stress Reduction (MBSR) is a secular form of meditation training. The vast majority of the extant literature investigating the health effects of mindfulness interventions relies on wait-list control comparisons. Previous studies have found that meditation training over several months is associated with improvements in cognitive control and attention. METHODOLOGY/PRINCIPAL FINDINGS: We used a visual continuous performance task (CPT) to test the effects of eight weeks of mindfulness training on sustained attention by comparing MBSR to the Health Enhancement Program (HEP), a structurally equivalent, active control condition in a randomized, longitudinal design (ClinicalTrials.gov, NCT01301105) focusing on a non-clinical population typical of MBSR participants. Researchers were blind to group assignment. 63 community participants were randomized to either MBSR (n = 31) or HEP (n = 32). CPT analyses were conducted on 29 MBSR participants and 25 HEP participants. We predicted that MBSR would improve visual discrimination ability and sustained attention over time on the CPT compared to HEP, with more home practice associated with greater improvements. Our hypotheses were not confirmed but we did find some evidence for improved visual discrimination similar to effects in partial replication of other research. Our study had sufficient power to demonstrate that intervention groups do not differ in their improvement over time in sustained attention performance. One of our primary predictions concerning the effects of intervention on attentional fatigue was significant but not interpretable. CONCLUSIONS: Attentional sensitivity is not affected by mindfulness practice as taught in MBSR, but it is unclear whether mindfulness might positively affect another aspect of attention, vigilance. These results also highlight the relevant procedural modifications required by future research to correctly investigate the role of sustained attention in similar samples. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01301105.

Temporal dynamics of emotional responding: amygdala recovery predicts emotional traits.

An individual's affective style is influenced by many things, including the manner in which an individual responds to an emotional challenge. Emotional response is composed of a number of factors, two of which are the initial reactivity to an emotional stimulus and the subsequent recovery once the stimulus terminates or ceases to be relevant. However, most neuroimaging studies examining emotional processing in humans focus on the magnitude of initial reactivity to a stimulus rather than the prolonged response. In this study, we use functional magnetic resonance imaging to study the time course of amygdala activity in healthy adults in response to presentation of negative images. We split the amygdala time course into an initial reactivity period and a recovery period beginning after the offset of the stimulus. We find that initial reactivity in the amygdala does not predict trait measures of affective style. Conversely, amygdala recovery shows predictive power such that slower amygdala recovery from negative images predicts greater trait neuroticism, in addition to lower levels of likability of a set of social stimuli (neutral faces). These data underscore the importance of taking into account temporal dynamics when studying affective processing using neuroimaging.

A comparison of mindfulness-based stress reduction and an active control in modulation of neurogenic inflammation.

Psychological stress is a major provocative factor of symptoms in chronic inflammatory conditions. In recent years, interest in addressing stress responsivity through meditation training in health-related domains has increased astoundingly, despite a paucity of evidence that reported benefits are specific to meditation practice. We designed the present study to rigorously compare an 8-week Mindfulness-Based Stress Reduction (MBSR) intervention to a well-matched active control intervention, the Health Enhancement Program (HEP) in ability to reduce psychological stress and experimentally-induced inflammation. The Trier Social Stress Test (TSST) was used to induce psychological stress and inflammation was produced using topical application of capsaicin cream to forearm skin. Immune and endocrine measures of inflammation and stress were collected both before and after MBSR training. Results show those randomized to MBSR and HEP training had comparable post-training stress-evoked cortisol responses, as well as equivalent reductions in self-reported psychological distress and physical symptoms. However, MBSR training resulted in a significantly smaller post-stress inflammatory response compared to HEP, despite equivalent levels of stress hormones. These results suggest behavioral interventions designed to reduce emotional reactivity may be of therapeutic benefit in chronic inflammatory conditions. Moreover, mindfulness practice, in particular, may be more efficacious in symptom relief than the well-being promoting activities cultivated in the HEP program.

The validation of an active control intervention for Mindfulness Based Stress Reduction (MBSR).

Most of the extant literature investigating the health effects of mindfulness interventions relies on wait-list control comparisons. The current article specifies and validates an active control condition, the Health Enhancement Program (HEP), thus providing the foundation necessary for rigorous investigations of the relative efficacy of Mindfulness Based Stress Reduction (MBSR) and for testing mindfulness as an active ingredient. 63 participants were randomized to either MBSR (n = 31) or HEP (n = 32). Compared to HEP, MBSR led to reductions in thermal pain ratings in the mindfulness- but not the HEP-related instruction condition (η(2) = .18). There were significant improvements over time for general distress (η(2) = .09), anxiety (η(2) = .08), hostility (η(2) = .07), and medical symptoms (η(2) = .14), but no effects of intervention. Practice was not related to change. HEP is an active control condition for MBSR while remaining inert to mindfulness. These claims are supported by results from a pain task. Participant-reported outcomes (PROs) replicate previous improvements to well-being in MBSR, but indicate that MBSR is no more effective than a rigorous active control in improving these indices. These results emphasize the importance of using an active control condition like HEP in studies evaluating the effectiveness of MBSR.

Cognitive Style Moderates Attention to Attribution-Relevant Stimuli.

Individuals with negative cognitive style are at high risk for depressive disorders; however, the mechanisms linking cognitive vulnerability to depression are not fully understood. Here, we use an attentional blink task to test whether stimuli associated with negative attributions are especially salient to individuals with high negative cognitive style. We found that individuals high in negative cognitive style were able to attend to negative attribution words during a period of time when attentional resources would ordinarily be depleted. These individuals were not more likely than those with low or moderate negative cognitive style to detect neutral and negative non-self-relevant words during this period. These data suggest that cognitive style modulates the saliency of material that is relevant to negative attributions, and these alterations in information processing may link cognitive style to development of depression.

Clarifying the factors that undermine behavioral inhibition system functioning in psychopathy.

Psychopathic individuals are generally unresponsive to motivational and emotional cues that facilitate behavioral regulation. A putative mechanism for this deficiency is Gray's (1981) behavioral inhibition system (BIS). To evaluate the association between psychopathy and BIS functioning, we administered a laboratory-based assessment of BIS functioning to a group of psychopathic offenders assessed with the Psychopathy Checklist­Revised (PCL­R; Hare, 2003). In addition, we tested the hypothesis that the effects of working memory load on BIS functioning would interact differentially with the PCL­R factors. Replicating previous results, psychopathic offenders were less sensitive to BIS-related cues than controls. As predicted, working memory load interacted with Factor 2 (antisocial/impulsive), with higher scores predicting weaker BIS functioning under high-load though not low-load conditions. Results suggest new insights concerning the relationship among working memory, reward sensitivity, and BIS functioning in psychopathy.

Validating a distinction between primary and secondary psychopathy with measures of Gray's BIS and BAS constructs.

Investigators commonly distinguish between primary and secondary psychopathy (H. Cleckley, 1976; D.T. Lykken, 1995), though there is a lack of consensus regarding the best means to achieve this distinction. To address the validity of using R. D. Hare's (2003) Psychopathy Checklist and the G. Welsh (1956) Anxiety Scale for this purpose, the authors used 2 measures of J. A. Gray's (1987) behavioral inhibition system/behavioral activation system (BIS/BAS). Following D. T. Lykken (1995) and D. C. Fowles (1980), the authors hypothesized that primary psychopathy would be associated with a weak BIS and a normal BAS, whereas secondary psychopathy would be associated with a strong BAS and a normal BIS. Results for primary psychopathy were as predicted. Results for secondary psychopathy clearly supported the strong BAS prediction but provided mixed support for the normal BIS prediction.