What contributes to individual differences in brain structure?

Individual differences in adult human brain structure have been found to reveal a great deal of information about variability in behaviors, cognitive abilities and mental and physical health. Driven by such evidence, what contributes to individual variation in brain structure has gained accelerated attention as a research question. Findings thus far appear to support the notion that an individual’s brain architecture is determined largely by genetic and environmental influences. This review aims to evaluate the empirical literature on whether and how genes and the environment contribute to individual differences in brain structure. It first considers how genetic and environmental effects may separately contribute to brain morphology, by examining evidence from twin, genome-wide association, cross-sectional and longitudinal studies. Next, evidence for the influence of the complex interplay between genetic and environmental factors, characterized as gene-environment interactions and correlations, is reviewed. In evaluating the extant literature, this review will conclude that both genetic and environmental factors play critical roles in contributing to individual variability in brain structure

Mindfulness may both moderate and mediate the effect of physical fitness on cardiovascular responses to stress: a speculative hypothesis

This Document is Protected by copyright and was first published by Frontiers. All rights reserved. it is reproduced with permission.The psychological construct of mindfulness refers to an awareness that emerges by intentionally paying attention to the present experience in a non-judgmental or evaluative way. This particular quality of awareness has been associated to several indicators of physical and psychological health, and can be developed using mindfulness-based interventions (MBIs), and therefore MBIs have been successfully applied as preventive and complementary interventions and therapies in medicine and psychology. Together with quiet sitting and lying meditation practices, mindful physical exercises such as "mindful walking" and "mindful movement" are key elements in MBIs and couple muscular activity with an internally directed focus, improving interoceptive attention to bodily sensations. In addition, MBIs seem to share similar mechanisms with physical fitness (PF) by which they may influence cardiovascular responses to stress. Based on these facts, it is feasible to raise the question of whether physical training itself may induce the development of that particular quality of awareness associated with mindfulness, or if one's dispositional mindfulness (DM) (the tendency to be more mindful in daily life) could moderate the effects of exercise on cardiovascular response to stress. The role of mindfulness as a mediator or moderator of the effect of exercise training on cardiovascular responses to stress has barely been studied. In this study, we have hypothesized pathways (moderation and mediation) by which mindfulness could significantly influence the effects of PF on cardiovascular responses to stress and discussed potential practical ways to test these hypotheses.Marcelo M. P. Demarzo is grateful to the CNPq - Brazilian National Council for Research and Technology Development for a postdoctoral fellowship under supervision of Professor Javier Garcia-Campayo ("Science without Borders Program"). The authors would like to thank the reviewers for the constructive environment for debating hypotheses and concepts presented herein, which effectively allowed the manuscript's development and improvement.Demarzo, MMP.; Montero-Marin, J.; Stein, PK.; Cebolla, A.; Guixeres Provinciale, J.; Garcia-Campayo, J. (2014). Mindfulness may both moderate and mediate the effect of physical fitness on cardiovascular responses to stress: a speculative hypothesis. Frontiers in Physiology. 5(105):1-8. doi:10.3389/fphys.2014.00105S185105Baron, R. M., & Kenny, D. A. (1986). The moderator–mediator variable distinction in social psychological research: Conceptual, strategic, and statistical considerations. 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G., & Moskowitz, J. T. (2011). The association between dispositional mindfulness, psychological well-being, and perceived health in a Swedish population-based sample. British Journal of Health Psychology, 16(2), 300-316. doi:10.1348/135910710x501683BREUS, M. J., & O’CONNOR, P. J. (1998). Exercise-induced anxiolysis: a test of the «time out» hypothesis in high anxious females. Medicine & Science in Sports & Exercise, 30(7), 1107-1112. doi:10.1097/00005768-199807000-00013Britton, W. B., Haynes, P. L., Fridel, K. W., & Bootzin, R. R. (2012). Mindfulness-Based Cognitive Therapy Improves Polysomnographic and Subjective Sleep Profiles in Antidepressant Users with Sleep Complaints. Psychotherapy and Psychosomatics, 81(5), 296-304. doi:10.1159/000332755BROWN, D. R., WANG, Y., WARD, A., EBBELING, C. B., FORTLAGE, L., PULEO, E., … RIPPE, J. M. (1995). Chronic psychological effects of exercise and exercise plus cognitive strategies. Medicine & Science in Sports & Exercise, 27(5), 765???775. doi:10.1249/00005768-199505000-00021Brown, K. W., Goodman, R. J., & Inzlicht, M. (2012). Dispositional mindfulness and the attenuation of neural responses to emotional stimuli. Social Cognitive and Affective Neuroscience, 8(1), 93-99. doi:10.1093/scan/nss004Brown, K. W., & Ryan, R. M. (2003). The benefits of being present: Mindfulness and its role in psychological well-being. Journal of Personality and Social Psychology, 84(4), 822-848. doi:10.1037/0022-3514.84.4.822CARSON, J. W., CARSON, K. M., GIL, K. M., & BAUCOM, D. H. (2006). MINDFULNESS-BASED RELATIONSHIP ENHANCEMENT (MBRE) IN COUPLES. Mindfulness-Based Treatment Approaches, 309-331. doi:10.1016/b978-012088519-0/50015-0Ciesla, J. A., Reilly, L. C., Dickson, K. S., Emanuel, A. S., & Updegraff, J. A. (2012). Dispositional Mindfulness Moderates the Effects of Stress Among Adolescents: Rumination as a Mediator. Journal of Clinical Child & Adolescent Psychology, 41(6), 760-770. doi:10.1080/15374416.2012.698724Creswell, J. D., Irwin, M. R., Burklund, L. J., Lieberman, M. D., Arevalo, J. M. G., Ma, J., … Cole, S. W. (2012). Mindfulness-Based Stress Reduction training reduces loneliness and pro-inflammatory gene expression in older adults: A small randomized controlled trial. Brain, Behavior, and Immunity, 26(7), 1095-1101. doi:10.1016/j.bbi.2012.07.006Cullen, M. (2011). Mindfulness-Based Interventions: An Emerging Phenomenon. Mindfulness, 2(3), 186-193. doi:10.1007/s12671-011-0058-1Demarzo, M. M. P., & Stein, P. K. (2012). Mental Stress and Exercise Training Response: Stress-sleep Connection may be Involved. Frontiers in Physiology, 3. doi:10.3389/fphys.2012.00178Dimidjian, S., & Kleiber, B. (2013). Being Mindful About the Use of Mindfulness in Clinical Contexts. Cognitive and Behavioral Practice, 20(1), 57-59. doi:10.1016/j.cbpra.2012.02.006Duncan, L. G., & Bardacke, N. (2009). Mindfulness-Based Childbirth and Parenting Education: Promoting Family Mindfulness During the Perinatal Period. Journal of Child and Family Studies, 19(2), 190-202. doi:10.1007/s10826-009-9313-7Edelman, D., Oddone, E. Z., Liebowitz, R. S., Yancy, W. S., Olsen, M. K., Jeffreys, A. S., … Gaudet, T. W. (2006). A multidimensional integrative medicine intervention to improve cardiovascular risk. Journal of General Internal Medicine, 21(7), 728-734. doi:10.1111/j.1525-1497.2006.00495.xFarb, N. A. S., Segal, Z. V., & Anderson, A. K. (2012). Mindfulness meditation training alters cortical representations of interoceptive attention. Social Cognitive and Affective Neuroscience, 8(1), 15-26. doi:10.1093/scan/nss066Fortney, L., & Taylor, M. (2010). Meditation in Medical Practice: A Review of the Evidence and Practice. Primary Care: Clinics in Office Practice, 37(1), 81-90. doi:10.1016/j.pop.2009.09.004Garcia, M. C., Pompéia, S., Hachul, H., Kozasa, E. H., de Souza, A. A. L., Tufik, S., & Mello, L. E. A. M. (2014). Is mindfulness associated with insomnia after menopause? Menopause, 21(3), 301-305. doi:10.1097/gme.0b013e31829996fcGarcia-Campayo, J., Navarro-Gil, M., Andrés, E., Montero-Marin, J., López-Artal, L., & Demarzo, M. M. (2014). Validation of the Spanish versions of the long (26 items) and short (12 items) forms of the Self-Compassion Scale (SCS). Health and Quality of Life Outcomes, 12(1), 4. doi:10.1186/1477-7525-12-4Gardner, F. L., & Moore, Z. E. (2012). Mindfulness and acceptance models in sport psychology: A decade of basic and applied scientific advancements. Canadian Psychology/Psychologie canadienne, 53(4), 309-318. doi:10.1037/a0030220Garland, E. L., Gaylord, S. A., Boettiger, C. A., & Howard, M. O. (2010). Mindfulness Training Modifies Cognitive, Affective, and Physiological Mechanisms Implicated in Alcohol Dependence: Results of a Randomized Controlled Pilot Trial. Journal of Psychoactive Drugs, 42(2), 177-192. doi:10.1080/02791072.2010.10400690Garland, S. N., Campbell, T., Samuels, C., & Carlson, L. E. (2013). Dispositional mindfulness, insomnia, sleep quality and dysfunctional sleep beliefs in post-treatment cancer patients. Personality and Individual Differences, 55(3), 306-311. doi:10.1016/j.paid.2013.03.003Goldin, P., Ziv, M., Jazaieri, H., & Gross, J. J. (2012). Randomized Controlled Trial of Mindfulness-Based Stress Reduction Versus Aerobic Exercise: Effects on the Self-Referential Brain Network in Social Anxiety Disorder. Frontiers in Human Neuroscience, 6. doi:10.3389/fnhum.2012.00295Grossman, P. (2011). Defining mindfulness by how poorly I think I pay attention during everyday awareness and other intractable problems for psychology’s (re)invention of mindfulness: Comment on Brown et al. (2011). Psychological Assessment, 23(4), 1034-1040. doi:10.1037/a0022713Gryffin, P. A., & Chen, W. C. (2013). 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Frontiers in Physiology, 4. doi:10.3389/fphys.2013.0031

Differential changes in self-reported aspects of interoceptive awareness through 3 months of contemplative training

Interoceptive body awareness (IA) is crucial for psychological well-being and plays an important role in many contemplative traditions. However, until recently, standardized self-report measures of IA were scarce, not comprehensive, and the effects of interoceptive training on such measures were largely unknown. The Multidimensional Assessment of Interoceptive Awareness (MAIA) questionnaire measures IA with eight different scales. In the current study, we investigated whether and how these different aspects of IA are influenced by a 3-months contemplative intervention in the context of the ReSource project, in which 148 subjects engaged in daily practices of “Body Scan” and “Breath Meditation.” We developed a German version of the MAIA and tested it in a large and diverse sample (n = 1,076). Internal consistencies were similar to the English version (0.56–0.89), retest reliability was high (rs: 0.66–0.79), and the MAIA showed good convergent and discriminant validity. Importantly, interoceptive training improved five out of eight aspects of IA, compared to a retest control group. Participants with low IA scores at baseline showed the biggest changes. Whereas practice duration only weakly predicted individual differences in change, self-reported liking of the practices and degree of integration into daily life predicted changes on most scales. Interestingly, the magnitude of observed changes varied across scales. The strongest changes were observed for the regulatory aspects of IA, that is, how the body is used for self-regulation in daily life. No significant changes were observed for the Noticing aspect (becoming aware of bodily changes), which is the aspect that is predominantly assessed in other IA measures. This differential pattern underscores the importance to assess IA multi-dimensionally, particularly when interested in enhancement of IA through contemplative practice or other mind–body interventions