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Researchers measured gray matter changes in 13 regular practitioners of Zen meditation and 13 control subjects matched for age and education level who never practiced meditation by employing voxel-based morphometry (VBM), a recent technique to measure gray matter changes from MRI brain scans, and a computerized task of sustained attention.
Researchers found that while both total gray matter volume and attentional performance displayed the expected decrease with age in control subjects, meditators did not show such a trend."