A binaural beat is an auditory illusion perceived when two different pure-tone sine waves, both with frequencies lower than 1500 Hz, with less than a 40 Hz difference between them, are presented to a listener dichotically (one through each ear). For example, if a 530 Hz pure tone is presented to a subject’s right ear, while a 520 Hz pure tone is presented to the subject’s left ear, the listener will perceive the auditory illusion of a third tone, in addition to the two pure-tones presented to each ear. The third sound is called a binaural beat, and in this example would have a perceived pitch correlating to a frequency of 10 Hz, that being the difference between the 530 Hz and 520 Hz pure tones presented to each ear. Each brainwave state is associated with different states of consciousness. You normally go in and out of different brainwave states depending on what you are experiencing. But it’s possible to manipulate your brain waves by meditating or by using binaural beats or other kinds of sound technology. Binaural beats cause your brain to synchronize, or entrain, itself with the beat frequency. This has the effect of inducing a desired brainwave pattern, letting you experience the benefits of that brainwave state at will.

Delta Brain Waves (below 4 Hz): Delta waves are the lowest frequency brain wave and occur during deep, dreamless, restorative sleep. Sleep is not simply the absence of being awake. It has its own stages and associated brainwave patterns.

Theta Brain Waves (4 – 7 Hz): Theta waves are associated with the drowsy state you experience as you are falling asleep or during light sleep. They can also be experienced during meditation. The theta state is characterized by deep relaxation, daydreaming, and creativity.

Alpha Brain Waves (8 – 15 Hz): Your brain enters the alpha brainwave state almost immediately whenever you close your eyes. Alpha waves are associated with relaxed wakefulness and can occur during light meditation. Many brainwave meditations seek to induce this state since it’s the alpha state that’s believed to facilitate a bridge between conscious thought and the unconscious mind.

Beta Brain Waves (16 – 31 Hz): As long as you are physically active and mentally alert, you probably spend most of your waking day in a beta state. Since the hallmark of the beta state is one of heightened alertness, it can be overdone. Spending too much time in the beta state leads to stress and anxiety.

Gamma Brain Waves (32 and above Hz): Gamma brain waves (not to be confused with gamma rays) are the highest frequency brain waves. They are the most recently discovered since they could not be measured until the development of digital electroencephalography. They are also the least understood. When in the gamma brainwave state, it is thought that the senses are sharpened, and feelings of happiness and peace predominate. It’s this state that you tap into whenever you’re in “the zone” — the state of peak performance. Heightened focus, super concentration, and massive productivity are all said to be yours when you’re in the gamma state. One study found that Buddhist monks can induce a gamma state through meditation.