Variations provide the ultimate source of rhythmic activity. I strive to be as active as they are. I want my brain activity to match theirs.
This requires me to stop restricting the number of musical events to which I respond at any given moment. Do not count - that is the first musical commandment!
Do not identify sounds - every satisfying sound is made up of so many variable components that, as soon as you identify that sound, you have probably killed off any chance of dealing with its many aspects.
Contrary to accepted wisdom on piano playing, I do not teach my students any theory whatsoever. Result: Those who react to sound never tire of it. What music do they love most? The music that makes the most imaginative use of sound: Haydn, Mozart, Beethoven, Bartok - can't beat it.