There’s a lot you can do to engage the brain’s machinery in ways that help keep it healthy as an organ.

The brain’s plasticity—its ability to change not just functionally, but physically and chemically too—is most heavily engaged by activities that are intensive, repetitive, and progressively changing. Those that emphasize refining the speed and accuracy of the brain’s sensory systems are most likely to help with other activities in daily life.

Look for activities that are demand your attention, make you feel reward, and consistently require you to master new elements. Those types of activities engage brain chemistry that’s beneficial for learning, remembering, and mood—by stimulating the production of acetylcholine (when paying attention), norepinephrine (when encountering something new), and dopamine (when feeling rewarded).

Here are some of our favorite brain healthy activities and why each makes the list.