Have you ever heard of Binaural Beat? Binaural beat refers to the feeling that when the left and right ears hear a slightly different audio frequency, the brain will produce a beat, which is synchronized with the brain’s Alpha wave and promotes relaxation and sleep.
Research has found that binaural beats are effective in shortening the time it takes to fall asleep and reducing heart rate variability and low-frequency heart rate power before and during sleep, reflecting a more stable and relaxed state of the body.