Article in Washington Post, Dec. 20, 2006
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http://www.washingtonpost.com/wp-dyn/content/article/2006/12/19/AR2006121901431.html
Muscles that aren't exercised regularly tend to become weak. Recent research indicates that brain cells are similar to muscles in this regard. Memory and brain fitness improve with stimulating brain exercises for all important areas of the brain. Crosswords alone are not enough because they don't exercise all parts of the brain. Brain exercise needs to include activities like drawing and learning a musical instrument.
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The concept of visiting an inner guide or guides exists in the Silva Method. It is also there in a meditation exercise written by Shakti Gawain.