What exactly it was that went wrong with J Dilla's body over the course of the last few years is between him and his doctors, but whatever it was kept him flat on his back for the better part of a year. For creative types, paralysis is a curious paradox: Forced isolation gave Kanye West one of his best singles, and if Donuts doesn't have anything with the temerity and determination of "Through the Wire," it's only because the record doesn't have any lyrics. For inventiveness and spirit and energy, though, Dilla's still got it down, and Donuts is the kind of crackling, worn-out breakbeat mix tape hip-hop was built on. Its chief strength is drawn from Dilla's ability to isolate the best seconds of a sample and loop them until they attain coherence. This kind of microscopic focus is fascinating, like building an entire movie out of a few frames of film. Cutting up old commercials ("Lightworks") and soul rarities ("One Eleven") with equal enthusiasm, Dilla scrawls a kind of aural surrealist graffiti. (Call it "Magritte Street.") And the tender cheer-up R&B snippet that's the center of "Don't Cry" collapses into a psyched-out hippie folk chestnut which folds up into searing '70s cop rock. The flesh may be weak, but the spirit? Boundless.