In general, meditation entails calming, regulated attention-focusing.
Playing board games or cards is also good for the brain.
One common exercise that may engage the brain is solving crossword puzzles.
Sudoku can be an enjoyable mental exercise. They might also help certain people's cognitive abilities.
Learning new skills engages the brain in different ways and may help improve brain function.
Regular physical exercise is beneficial for both the brain and the body
Sleep is essential for the body and the brain, even if it isn't necessary an active activity.