Researchers from Harvard, Yale, and MIT have found that regular meditation can significantly alter the structure of the adult brain. The study compared scans from 20 experienced meditators and 15 non-meditators to those of those practicing Buddhist "insight meditation". The study found that the cortexes of meditator were thicker by 4 to 8 thousandths of an inch in key areas, which was more pronounced in older participants. The most pronounced effects were found in participants who meditate more deeply, measured by slow breathing. The researchers also found that meditation improved focus, reduced stress, and increased emotional resilience.