Eli5 why is it hard to tap your head and rub your belly at the same time then switch hands?

Question

Eli5 why is it hard to tap your head and rub your belly at the same time then switch hands?

In: 2

Answer 1

Basically, moving both arms in the same way is easy because you only have to think of one movement, and just copy it on both sides. To tap your head and rub your belly at the same time, you need to use more brain power to concentrate on your movement(s). That’s why getting into the rhythm of it is hard, but easy once you get used to it and don’t have to focus on it as much. Switching it would disrupt this rhythm, making it more difficult. With practice it would get easier to switch randomly, because of muscle memory. But picking up on new movements would still be more challenging than just moving your arms in unison

So TLDR; similar movements = less brain power, movements that aren’t very similar = more brain power