Eight weeks of mindfulness meditation training reduced right amygdala activation in healthy adults when viewing positive emotional images, even when they were not actively meditating. A compassion-based meditation program showed a trend toward increased right amygdala response to negative images, which correlated with lower depression scores. No changes occurred in a control group. The results suggest meditation training can alter emotional processing in the brain during ordinary, non-meditative states, indicating that such training may produce lasting, process-specific changes in mental function rather than only task-specific effects.
In veterans with PTSD, mindfulness-based stress reduction (MBSR) and present-centered group therapy both increased morning cortisol levels from baseline to 9 weeks, but the increase was significantly smaller with MBSR (mean difference 1.69 ± 0.8 SE). Changes in interleukin-6 and C-reactive protein did not differ between groups. Greater self-reported mindfulness was linked to higher cortisol and to reduced PTSD and depression severity. Higher IL-6 and CRP were associated with less severe PTSD but not depression. Pooled results confirmed MBSR outperformed the active control for clinical improvement. Increased mindfulness may recalibrate cortisol levels, suggesting a therapeutic response.
Training in compassion meditation for six weeks did not, on average, reduce stress-induced inflammation, cortisol, or distress compared to a health discussion control group. However, among those who meditated more, greater practice time was linked to smaller increases in the inflammatory marker interleukin-6 and lower self-reported distress after a standardized stress test. People who meditated above the median amount showed less stress reactivity than those who meditated less or were in the control group. The findings suggest that regularly engaging in compassion meditation may dampen immune and emotional responses to stress, but more research is needed to confirm this link.