In Björk's new album Medúlla musical instruments have been, for the most part, eliminated, and replaced by sounds of human voices. This brings a very strong sense of the "organic" to these tunes, even when the voices have been sampled, altered and programmed.
I have learned long ago not to judge her work on first listen. These compositions are carefully constructed in accordance with some internal logic, on both musical and spiritual levels. Careful consideration will bring great rewards - for the open-minded.
Innumerable love songs have been written with the heart as a central metaphor. Indeed, the heart as a symbol of life, of being, has been used in the arts since the ancients. Nowhere (that I'm aware of) has a song been written as a paean to the heart as a biological organ. The climax of the album is the track Triumph of a Heart in which Björk's muse turns literally inward, in a biological sense. Circulation, respiration and elimination are dealt with in a clinical, yet "joyful" way.
If you haven't yet gotten into this artist's work, this might not be the place to start. But for those willing to to explore, this is uncharted territory.