Music has an undeniable power. Our emotions are affected by music. However, its effects extend far beyond our surface experience of song and rhythm. At a symphony performance, you've heard the musicians tune their instruments to the same note before they begin playing together. One instrument, if slightly out of tune, is brought into tune by other instruments, in a seemingly magical but actually natural phenomenon known as "entrainment," the process of waveforms synchronizing. As a result, the sound is expressed harmoniously.