Long-term mindfulness meditators show greater gray matter concentration in brain regions linked to interoceptive awareness and meditation, including the right anterior insula, left inferior temporal gyrus, and right hippocampus. In a comparison of 20 Vipassana meditators (averaging 8.6 years of practice, 2 hours daily) with matched non-meditators, the amount of meditation training predicted gray matter concentration in the left inferior temporal gyrus, suggesting a causal impact of practice. The findings indicate that meditation practice is associated with structural brain differences in areas typically activated during meditation and relevant to the task.
Pain can be modulated by mindfulness, but the underlying brain mechanisms differ from those of other cognitive techniques. Mindfulness practitioners reduced pain unpleasantness by 22% and anticipatory anxiety by 29% during a mindful state, while controls did not. In the brain, this reduction was associated with decreased activation in the lateral prefrontal cortex and increased activation in the right posterior insula during stimulation, and increased rostral anterior cingulate cortex activation during pain anticipation. These findings indicate a unique mechanism of pain modulation involving increased sensory processing and decreased cognitive control, contrasting with established mechanisms.
During mindfulness of breathing, experienced Vipassana meditators show stronger brain activation in the rostral anterior cingulate cortex and dorsal medial prefrontal cortex compared to non-meditators. The rostral anterior cingulate cortex activation may reflect enhanced processing of distracting events, while medial prefrontal cortex activation suggests stronger engagement in emotional processing. Fifteen meditators with an average of 7.9 years of daily two-hour practice and fifteen matched non-meditators participated in an fMRI study comparing meditation to mental arithmetic.