Mindfulness, Experiential Avoidance, and Affective Experience in Older Adults.

Subjective well-being is comprised of two components: affective experience and life satisfaction. Older adulthood is marked by changes and challenges that have the potential to diminish well-being. As the proportion of older adults in the population rises, it is becoming increasingly important to identify factors that may be protective against these potentially detrimental events. Mindfulness and acceptance constructs have been shown to be associated with affective experience across the lifespan. However, little work has examined which facets of mindfulness drive these associations. The current study aimed to explore the associations between acceptance and mindfulness processes and positive and negative affect in older adults. Eighty-five healthy older adults completed self-report measures of mindfulness, experiential avoidance, and positive and negative affect. Results from linear regression analyses indicated that the act with awareness and nonreactivity facets of mindfulness were particularly important in their contribution to positive affect. Additionally, higher levels of experiential avoidance accounted for significant variance in negative affect. These findings help to elucidate how mindfulness and acceptance processes play a role in affective experience in older adults. Future studies should explore these facets in clinical populations to help create more targeted clinical goals.

Acceptance- and Mindfulness-Based Interventions for Health Behavior Change: Systematic Reviews and Meta-Analyses.

Behavioral health issues such as smoking and overweight are risk factors for a variety of adverse health outcomes, including mortality. Over the past decade, a growing number of randomized controlled trials have examined the efficacy of acceptance- and mindfulness-based interventions for smoking cessation and weight loss. The purpose of the current meta-analytic reviews was to quantitatively synthesize the existing literature comparing these interventions to controls for a) smoking cessation and b) weight loss outcomes. Searches identified 17 smoking cessation studies and 31 weight loss studies eligible for inclusion. Meta-analytic results indicated a non-significant effect favoring acceptance- and mindfulness-based interventions over controls for smoking cessation (OR = 1.13) and a small, significant effect favoring these interventions over controls for weight loss outcomes (Hedge's g = 0.30). Statistical heterogeneity and risk of bias were assessed. Subgroup and meta-regression analyses were conducted to examine moderating variables (e.g., sample and intervention characteristics). The findings indicated that acceptance- and mindfulness-based interventions were at least as efficacious as active control conditions. Given the significant health risks associated with smoking and overweight, these findings have important clinical and public health implications. Limitations (e.g., relative infancy of the literature; lack of diversity in sample demographics) and future directions (e.g., further exploration of mediators and moderators of change) are discussed.

Does gender play a role in functional asymmetry of ventromedial prefrontal cortex?

We found previously in a lesion study that the right-sided sector of the ventromedial prefrontal cortices (VMPCs) was critical for social/emotional functioning and decision-making, whereas the left side appeared to be less important. It so happened that all but one of the subjects in that study were men, and the one woman did not fit the pattern very well. This prompted a follow-up investigation, in which we explored the following question: Does gender play a role in the development of defects in social conduct, emotional functioning and decision-making, following unilateral VMPC damage? We culled from our Patient Registry same-sex pairs of men or women patients who had comparable unilateral VMPC damage in either the left or right hemisphere. Two male pairs and one female pair were formed, and we included two additional women with unilateral right VMPC damage (8 patients in all). The domains of measurement covered social conduct, emotional processing and personality, and decision-making. We found a systematic effect of gender on the pattern of left-right asymmetry in VMPC. In men, there were severe defects following unilateral right VMPC damage, but not following left-sided damage. In women, there were defects following unilateral left VMPC damage; following right-sided damage, however, defects were mild or absent. The findings suggest that men and women may use different strategies to solve similar problems--e.g. men may use a more holistic, gestalt-type strategy, and women may use a more analytic, verbally-mediated strategy. Such differences could reflect asymmetric, gender-related differences in the neurobiology of left and right VMPC sectors.

The effects of vagus nerve stimulation on decision-making.

Subcortical and brainstem structures are increasingly becoming recognized as important contributors to higher cognitive functioning. Decision-making is one such function, particularly as viewed within the framework of the somatic marker hypothesis (SMH). The SMH views the participation in decision-making by the body proper as integral to emotional biasing and hence key to choosing in an advantageous manner. This study focuses on the vagus nerves as a possible conduit for somatic afferent signals pertinent to decision-making. We tested eight epileptic patients with implanted left vagus nerve stimulators. To assess decision-making we used the gambling task, which is sensitive to real-life decision-making deficits. Using a counterbalanced design, each participant performed the gambling task under a condition in which low-level vagus nerve stimulation (VNS) was covertly delivered, and another condition in which no VNS was delivered. Participants showed improved performance, that is, made more advantageous choices, in the stimulated relative to the unstimulated condition. Although these results should be viewed as preliminary, they suggest that the vagus nerve is a conduit for afferent somatic signals that can influence decision-making.