Yes, I know notes and tonality are important aspects of music, but take a second a do something for me to help me prove my point: find someone, anyone, and, without saying the words or singing pitches, verbalize the rhythm of Michael Jackson's "Thriller". See how long it takes them to figure it out.
Now, of course, if you had sung the words and the melody in rhythm of the song it wouldn't have taken as long, but this exercise goes to show that the rhythm of music we hear is more important than the words or the notes of the song. And what do people do when they don't know the words or the rest of the melody? They use the rhythm they know from the song to "fill in the blanks". And that is part 2 of our exercise on patters.
Take the patterns I used in part 1, or make your own, and now think of a phrase or a sentence. It can be something you read. Say it and listen to the rhythm of that sentence or phrase. Now use that rhythm as a base and put notes on top of it. Then move the notes around as you repeat the rhythm.
Now, by this point you're probably thinking, "Nope, can't do it." Well, I have some proof that even an 8-year-old can do this- and she's been playing piano for only a year (maybe it's a little unfair since she's my daughter, so she has my DNA :D )! I showed her some notes she could use and reinforced the idea of using a rhythmic pattern, and voila!, here is the final product: