Brainwave entrainment through audio can be triggered through a variety of techniques, including binaural beats, isochronic tones, monaural beats, and modified audio tracks. The brainwavetones are embedded into the audio and the listener is unaware of their presence. He or she simply enjoys the audio track as a pleasurable listening experience, while the various tones generate frequencies in a way that encourages the brainwaves to respond and “get in step.”
A more extensive study of over 100 participants who were undergoing general anesthesia for a day procedure, reported a decrease in pre-operative anxiety. The participants in this study listened to 30 minutes of binaural beats before surgery, but the researchers noted that people experiencing high levels of pre-operative anxiety could listen to binaural beats for up to 1 hour before anesthesia to reduce levels of anxiety.