binaural beat

Binaural beats are a perceptual phenomenon that occurs when two tones with slightly different frequencies are presented separately to each ear. The brain processes these separate auditory signals, and under certain conditions, a pulsing or throbbing sensation, known as a beat, can be perceived. This is distinct from monaural beats, which arise from the combination of harmonics within a single sound.12

The principle of beats is fundamental in physics and has practical applications, such as in tuning musical instruments or detecting ultrasonic vibrations. When two waves with nearly identical frequencies combine, their amplitudes fluctuate, creating the audible beat. The frequency of these beats is the difference between the frequencies of the two original waves.2