Brainwave Entrainment is not new. in fact our ancestors used it in their dances and rituals. They used drums and other types of rhythmic instruments like rattles to create beats which would have a certain effect on those listening.

A very fast beat would whip people into a frenzy to prepare them for battle or any activity which required a lot of energy and enthusiasm. Other slower beats would calm people down almost to a dreamlike meditative state necessary for healing or to implant ideas into the subconscious minds of the listeners.

When we’re awake we are mainly in a state of beta,

via Natural Sleep Aids.