Look into hemisync/holosync/binaural beats. They create a beat in the music by pulsing a tiny delay between left and right channel. That pulse was shown to bri

Look into hemisync/holosync/binaural beats. They create a beat in the music by pulsing a tiny delay between left and right channel. That pulse was shown to bring the brain wave frequence in sync with itself. I find the effect easy to discern when listening in a way where the two channels are clearly separated (as when via headphones).