I'm pretty sure this is wrong. The brain adapts to whatever activity you do and, as far as I know, is way more plastic than researchers thought decades ago. If

I'm pretty sure this is wrong. The brain adapts to whatever activity you do and, as far as I know, is way more plastic than researchers thought decades ago. If you're doing dumb things all the time you're making yourself dumber over time and when you're performing difficult tasks repeatedly and daily your brain adapts to them to be able to solve them easier. I realized that a long time ago in a completely different area, in martial arts. When you start it's extremely hard to follow complex movements shown by other people. Beginners struggle with this a lot. Over the years it's getting easier and easier and you can often grasp complicated movements after seeing them once. I suppose it's the same in dancing and ballet. The brain adapts to sports, painting, writing poems, or solving complex math puzzles. It just happens that some of these activities are considered smart and also (partly) measured with traditional IQ tests. You can even train to become better at IQ tests if you desire to acquire a completely useless skill set.