First it's the beeping of a heart monitor. A nurse comes in to take a patient's temperature. There's conversation during the shift change, overhead pagers, a visitor's cellphone conversation and the din of a TV talk show. An aide pushes a cart of rattling dishes. An alarm goes off when IV medication is finished.

All these sounds make up the steady assault of beeps and bustle during a typical night in a hospital bed. More hospitals are getting creative about lowering the noise level, masking intrusive sound and distracting...