To learn is to change how you think.

If a brain is exercised properly, anyone can grow intelligence, at any age, and potentially by a lot. Or you can just let your brain idle - and watch it slowly, inexorably, go to seed like a sedentary body.

Your brain - every brain - is a work in progress. It is 'plastic.' From the day we're born to the day we die, it continuously revises and remodels, improving or slowly declining, as a function of how we use it.

To learn is to change how you think.

Rather marvelously, the older brain only permits change when it judges that change to be important, rewarding or good for it.

Learning a new skill can change hundreds of millions of cortical connections.

The Internet is just one of those things that contemporary humans can spend millions of "practice" events at, that the average human a thousand years ago had absolutely no exposure to. Our brains are massively remodeled by this exposure--but so, too, by reading, by television, by video games, by modern electronics, by contemporary music, by contemporary "tools," etc.