Two studies based on a nine-month investigation (called the ReSource Project) report long-term mental exercises may induce exercise-specific restructuring in the brain and reduce some indicators of stress. Taken together, the findings hint that short, daily mental practices can influence changes in the brain. While recent mental training research in humans has begun to address the changes in gray matter volume (which contains most of the neuronal cells in the brain) following mindfulness or meditation exercises, most analyses focus on meditation practitioners, rather than directly assessing individuals who are new to meditation. What's more, the few longitudinal studies that have been conducted were small, lacked control groups, and were unable to examine the effects of mental practices on changes in brain function and structure within the same trainees. To investigate whether the targeted mental training of different cognitive and social skills can induce specific changes in brain morphology, Sofie Valk et al. collected MRI data on participants between 20 and 55 years of age throughout mental training intervention. The training groups underwent three types of three-month exercise modules with weekly-instructed group sessions and daily individual exercises completed via smart phone and online. The scientists found module-specific changes in cortical thickness with MRI measures, a result that correlated with individual improvements in attention, compassion and cognitive perspective-taking.
A second study evaluated whether different mental training practice types were effective means for psychosocial stress reduction. After three months of training with each exercise module, Veronika Engert and colleagues examined participants' responses to the Trier Social Stress Test, a motivated performance task mimicking the type of every-day experiences that eventually accumulate to chronic stress. They assessed self-reported stress responses, as well as levels of the hormone cortisol, heart rate and markers of stress-influenced immune activity. Relative to the control group, all three practice modules reduced self-reported stress reactivity in healthy participants. However, only the training of intersubjective skills lessened the body's stress response, specifically the secretion of cortisol. Contrary to past studies, the researchers saw no effect of mental training on immune markers. The authors say their research could promote the development of mental training interventions in clinical, educational, and corporate settings, further noting that short, daily intersubjective mental practice may be a broadly accessible, low-cost approach to prevent stress-related disease and the associated financial burden to society.