Sex-divergent findings re hippocampal dimensions

Luders, E., Thompson, P. M., & Kurth, F. (2015). Larger Hippocampal Dimensions in Meditation Practitioners: Differential Effects in Women and Men. Frontiers in Psychology, 6, 186. To access full text, go to Abstract and retrieve provisional PDF.

hippopotamus-baby-beautiful-164-1On average, the human hippocampus shows structural differences between meditators and non-meditators as well as between men and women. However, there is a lack of research exploring possible sex effects on hippocampal anatomy in the framework of meditation.

Thus, we obtained high-resolution magnetic resonance imaging data from 30 long-term meditation practitioners (15 men / 15 women) and 30 well-matched control subjects (15 men / 15 women) to assess if hippocampus-specific effects manifest differently in male and female brains.

Hippocampal dimensions were enlarged both in male and in female meditators when compared to sex- and age-matched controls. However, meditation effects differed between men and women in magnitude, laterality, and location on the hippocampal surface. Such sex-divergent findings may be due to genetic (innate) or acquired differences between male and female brains in the areas involved in meditation and/or suggest that male and female hippocampi are differently receptive to mindfulness practices.

Efficacy of meditation on stress-related outcomes (review)

Goyal, M., et al.  (2014). Meditation Programs for Psychological Stress and Well-Being. Comparative Effectiveness Reviews, No. 124. Full text.

Objective: Meditation, a mind-body method, employs a variety of techniques designed to facilitate the mind’s capacity to affect bodily function and symptoms. An increasing number of patients are using meditation programs despite uncertainty about the evidence supporting the health benefits of meditation. We aimed to determine the efficacy and safety of meditation programs on stress-related outcomes (e.g., anxiety, depression, stress, distress, well-being, positive mood, quality of life, attention, health-related behaviors affected by stress, pain, and weight) compared with an active control in diverse adult clinical populations.

Conclusions: Meditation programs, in particular mindfulness programs, reduce multiple negative dimensions of psychological stress. Stronger study designs are needed to determine the effects of meditation programs in improving the positive dimensions of mental health as well as stress-related behavioral outcomes.

EEG measures manifestations of nondual awareness

Berman, A. E., & Stevens, L. (2015). EEG manifestations of nondual experiences in meditators. Consciousness and Cognition, 31, 1-11. Abstract

Highlights • Nondual states of consciousness reflect the culminating meditation experience. • These resulting states are differentiated from method or type of practice. • EEGs were recorded during meditation and states of nonduality. • Results suggest nondual states are neurologically distinct from general meditation. • Differentiating method and state will contribute to a more comprehensive taxonomy.

The holistic experiential benefits of meditation among a widely ranging population have been well established within the empirical literature. What remain less clear are the underlying mechanisms of the meditative process. A large impediment to this clarity is attributable to the lack of a unified and comprehensive taxonomy, as well as to the absence of clear differentiation within the literature between method of practice and resulting state.

The present study discusses and then attempts to identify within our sample a theoretically universal culminating meditative state known as Nondual Awareness, which is differentiated from the method or practice state. Participants completed an in-lab meditation, during which neurological patterns were analyzed using electroencephalography (EEG).

Analyses indicated significantly higher EEG power among slower wave frequencies (delta, theta, alpha) during the reported nondual events. These events appear neurologically distinct from meditation sessions as a whole, which interestingly demonstrated significant elevation within the gamma range.

Meditation and quality of life in people with MS

Levin, A.B., Hadgkiss, E.J., Weiland, T.K., Jelinek, G.J. (2014). Meditation as an Adjunct to the Management of Multiple Sclerosis. Neurology Research International. Full text.

From the Abstract. To explore the association between band health related quality of life (HRQOL), depression, fatigue, disability level, relapse rates and disease activity in a large international sample of people with multiple sclerosis.

Participants were invited to take part in an online survey and answer questions relating to HRQOL, depression, fatigue, disability, relapse rates and their involvement in meditation practises.

Statistically and potentially clinically significant differences between those who meditated once a week or more, and participants who never meditated were present for mean mental health composite scores, cognitive function scale and health perception scale. … Physical health composite scores were higher in those that meditated, however, the differences were probably not clinically significant. Among those who meditated, fewer screened positive for depression, but there was no relationship with fatigue or relapse rate. Those with worsened disability levels were more likely to meditate.

Improves academic performance by middle school students

Tang, Y. Y., Tang, R., Jiang, C., & Posner, M. I. (2014). Short-Term Meditation Intervention Improves Self-Regulation and Academic Performance. Journal of Child Adolescent Behavior, 2(154), 2. Full text (open access).

From the Abstract. Research has found that improved higher effortful control, a measure of self-regulation, improves performance of middle school students. Integrative body-mind training (IBMT) has been shown to improve attentional networks related to self-regulation. We hypothesize that an IBMT intervention will improve academic performance of adolescents.

Students age 13-18 were recruited from middle and high school in Beijing, China and randomly assigned to either IBMT or a relaxation training control (RT). Students were given 6 weeks of IBMT intervention with 30 min per day at school. The improved performance in attention and aspects of academic performance were measured.

Compared to RT, IBMT intervention showed significantly greater improvement in attention and in academic performance (scores of literacy, math, and second language).

Problems associated with meditation

Lomas, T., et al. (2014). A Qualitative Analysis of Experiential Challenges Associated with Meditation Practice. Mindfulness, 1-13. Full text.

Abstract. Although empirical interest in meditation has flourished in recent years, few studies have addressed possible downsides of meditation practice, particularly in community populations. In-depth interviews were conducted with 30 male meditators in London, UK, recruited using principles of maximum variation sampling, and analysed using a modified constant comparison approach.

Having originally set out simply to inquire about the impact of various meditation practices (including but not limited to mindfulness) on men’s wellbeing, we uncovered psychological challenges associated with its practice. While meditation was generally reported to be conducive to wellbeing, substantial difficulties accounted for approximately one quarter of the interview data. Our paper focuses specifically on these issues in order to alert health professionals to potential challenges associated with meditation.

Four main problems of increasing severity were uncovered: Meditation was a difficult skill to learn and practise; participants encountered troubling thoughts and feelings which were hard to manage; meditation reportedly exacerbated mental health issues, such as depression and anxiety; and in a few cases, meditation was associated with psychotic episodes. Our paper raises important issues around safeguarding those who practise meditation, both within therapeutic settings and in the community.

Mindful attention regulation in depression

Rohde, K., et al. (2014). Mindful Attention Regulation and Non-judgmental Orientation in Depression: A multi-method approach. Biological psychology, 10, 143. Abstract.

The use of questionnaires to measure two facets of mindfulness, ‘regulation of attention’ and ‘non-judgmental orientation,’ has been criticized. Furthermore, the assumption that depressed individuals show deficits in both facets has not yet been proven. In an attempt to minimize several biases associated with mindfulness questionnaires, we asked 43 currently depressed and 36 never-depressed participants to observe their breathing.

The ‘regulation of attention’ facet of mindfulness was measured by the number of times participants’ focus drifted off of their breathing. The ‘non-judgmental orientation’ facet was assessed using skin conductance response (SCR) and corrugator activity measured by electromyography (EMG), as indicators associated with arousal and negative emotions following drifting, and also by a self-report questionnaire.

Depressed patients showed deficits in both facets of mindfulness. Specifically, compared to never-depressed controls, depressed patients drifted focus from their breathing more often, had significantly higher self-reported self-criticism, and displayed an increase in corrugator activity after drifting from breathing