When a book starts and ends with music, you know it's a big deal for both the characters and the author. We feel safe in saying that Francisco X. Stork is both a Keith Jarrett fan and a classical music fan, given that Jasmine's hero is the former and Marcelo's favorite genre is the latter. Anyone who mentions Glenn Gould in his book probably grooves on some Bach himself.
But it's not all about the author being a fanboy. Let's go back to the IM, or Internal Music, for just a minute here. The music in his head is one of the most interesting things about Marcelo; after all, doctors don't just study any boring old brain. The fact that Marcelo's brain generates music as real as any outside tunes is so fascinating to Dr. Malone that he's spent years taking pictures of it and designing experiments around it.
However, as Marcelo goes from his sheltered world to the larger world, he finds that his IM is fading. It's not until Jasmine kisses him (shades of Snow White here, folks?) that he gets it back: "And when she steps out, I hear or I remember, I can't tell which, the most beautiful of melodies" (31.85). It's easy for us to tell which, of course: there's probably not a chamber orchestra that just popped up all of a sudden. He's remembering (which is what he's always called it when he hears the IM) an essential part of himself through interaction with someone else—someone who understands that part. It takes someone who really listens to him to allow Marcelo to listen to himself again.
Then there's Jasmine's CD collection. Her room is filled with them, and she gives one to Marcelo the first time he visits. She knows what CDs (and music) mean to him, so when she takes him to her room, she shows him her favorite Keith Jarrett joint. Marcelo sees Jarrett's bowed head on the cover and tells his new BFF Jasmine that Jarrett is "remembering," which is what he calls it when he listens to the IM and when he prays.
The response? "Jasmine takes the CD from my hand and studies it as if to see what I see. Then she puts it back in my hand. She turns and stands in front of me, and when she does that I suddenly feel like laughing" (14.113). Whoa. This real world person is actually attempting to communicate with Marcelo in his own language. His mind is officially blown.
CDs are also how Marcelo and Jasmine talk about Wendell's power plays. Marcelo says, "Jasmine asked me once if I was greedy about something and it must be that what consumes Wendell is like the greed I feel for a CD, only more desperate and reckless" (14.4). When Marcelo told Jasmine he was greedy for CDs, she said, "Well, when I'm around Wendell, I feel like that CD would if it could feel" (9.67). Message received.
If you're used to listening to music as MP3s—because let's face it, CDs are kind of ancient technology now—back up a minute and think about music as a physical object. When Jasmine puts her Keith Jarrett CD in Marcelo's hands, she's giving him an actual thing that he can take with him (as opposed to just sending him a song via email). When he holds it, opens it, and puts it in the CD player, he'll think of her. It's like she's handing over a little piece of herself, the piece she doesn't want to give to Wendell. (The way Wendell treats people is kind of like drooling all over a CD, shoplifting it, sticking it into your coat pocket with some old gum wrappers and used tissues, and scratching it the first time you play it.)