Importance of Brain Exercise

‘Use-it-or-lose-it’ brain theory put to the test - Aging - MSNBC.com: Mind exercises help keep seniors sharp for years to come"
Brief sessions of brain exercise can have long-lasting benefits for elderly people, helping them stay mentally fit for at least five years, one of the most rigorous tests of the “use-it-or-lose-it” theory suggests.
For people age 73 on average, just 10 sessions — less time than it takes to stay physically fit — helped keep their brains sharp.
The brain training involved hour-long classes and included exercises done on a computer. While it is uncertain if similar results would occur with mental exercise done at home, other research has shown that intellectual tasks such as crossword puzzles and reading can help keep the brain sharp as people grow old.

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