In my shamanic practice, I use the rattle as a sacred tool. When working with the rattle, the sound and the rhythm of the rattle shifts consciousness from an ordinary state into what is called a shamanic state of consciousness.
Once the shaman achieves a state of shamanic consciousness, the shaman is then able to travel across the veil into the hidden realms where the healing work occurs. The rattle is also used to call in the compassionate helping spirits to assist in healing work or to assist in a sacred healing ceremony.
Shamans also work with rattles to "shake out" negative energies from a person that may be plaguing them and/or leading to an illness. Rattles can also be shamanically empowered to become a healing rattle that is worked with for healing purposes on behalf of an individual. There are various ways in which shamans work with rattles and many develop their own ways that are specific to their healing practices.