Sound is Nourishment
We call it sonic nourishment. Sound facilitates shifts in our brainwave state, breath rate, and heartbeat through entrainment. Entrainment synchronizes our fluctuating body rhythms by providing a stable frequency it can attune to. By using rhythm and frequency, we can entrain our brainwaves and it then becomes possible to down-shift our normal beta state (normal waking consciousness) to alpha (relaxed consciousness), and even reach theta (meditative state) and delta (sleep; where internal healing can occur).
This same concept is utilized in meditation by regulating the breath, and with sound, it’s the frequency that is the agent that influences the shift.