So, i am / was a musician. As a teen (late 80s) i was REALLY into Metallica. One thing i would do to entertain myself while riding the bus is to listen to one of the tracks in my head and individually isolate instruments. I remember being able to listen to just the drum track, and then do things like get rid of the high-hat or toms.
Admittedly, I'd listened to those songs HUNDREDS of times.