Hi, I thought you may like this Mentalrobics exercise from Braingle.com:
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Meditation Builds the Brain

A new study provides evidence that people who meditate are improving their brains. MRI brain scans showed that meditating can increase the thickness of the cortex by causing blood vessels to expand and neurons to have increased branching. The areas that involve attention and sensory processing seem to be the most affected.

In a different study, sleep-deprived volunteers were given mental reaction tests. They were then instructed to either take a short nap or meditate. They were then retested. The volunteers who meditated showed superior performance on the tests, even though they had no prior experience with meditation.
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