The brain acts like a muscle: The more activity you do, the larger and more complex it can become. Whether that equates to more intelligence is another issue, but one fact is indisputable; What you do in life physically changes what your brain looks like. You can wire and rewire your brain with the simple choice of which musical instrument---or professional sport---you play
John Medina, Brain Rules: 12 Principles for Surviving and Thriving at Work, Home, and School
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