Impact of short- and long-term mindfulness meditation training on amygdala reactivity to emotional stimuli.
Level 2 - randomized trial
Individual randomized controlled trial combined with a cross-sectional cohort comparison
PubMed 29990584 · doi:10.1016/j.neuroimage.2018.07.013
What was done
Healthy adults were evaluated using BOLD functional MRI during exposure to emotional pictures across three groups: long-term meditators (n = 30; mean 9,081 lifetime practice hours), an 8-week Mindfulness-Based Stress Reduction (MBSR) group (n = 32), and an active control group (n = 35) participating in a randomized controlled trial. Investigators evaluated amygdala reactivity and functional connectivity between the amygdala and the ventromedial prefrontal cortex (VMPFC).
What was found
The abstract reports directional findings without numerical effect sizes, test statistics, or p-values: meditation training was associated with less amygdala reactivity to positive pictures relative to controls, with no group differences in response to negative pictures. Among long-term meditators, hours of retreat practice correlated with lower amygdala reactivity to negative pictures, but this relationship was not seen for MBSR practice time. Short-term training increased functional connectivity between the amygdala and the VMPFC during affective picture viewing compared to the active control.
Why it matters
This study provides neural evidence that short-term mindfulness training can strengthen prefrontal-amygdala connectivity involved in emotion regulation, while direct downregulation of amygdala responses to negative stimuli may require extensive, intensive practice.
Limits
The abstract provides no quantitative values, effect sizes, or confidence intervals. Sample sizes per arm are modest (30 to 35 participants). The long-term meditator group is cross-sectional and non-randomized, introducing potential confounding. The study was conducted exclusively in healthy adults, limiting direct generalizability to clinical populations with mood or anxiety disorders.
Cited by
- supports Research by Richard Davidson and others shows that an eight-week meditation program induces measurable changes in brain function and activity in meditation novices.