About Binaural Beats

Binaural beats is a brain response when presented with two slightly different tonal changes in a stereo situation. When a person is presented with the two different tones - the brain produces a response (binaural beat) that produces an altered state in brainwaves and therefore a hypnotic trance or super learning type environment.

 

Binaural beats are auditory brainstem responses which originate in the superior olivary nucleus of each brain hemisphere. They result from two different auditory impulses or sounds, heard from opposite ears. This binaural beat is consciously heard as the human hearing range is from 20-20,000 Hz. Rather it is perceived as an auditory beat and theoretically is being used coach certain brain rhythms from what is called the frequency-following response (the tendency for the brain to resonate at the frequency of an external stimulus).

 

When signals of two different frequencies (sounds) are presented, one to each ear, the brain detects phase differences between these signals. The brain processes this anomalous information differently when these phase differences are heard with stereo headphones or speakers. A perceptual integration of the two signals in perceived in the brain, producing the sensation of a third "beat". The difference between the signals waxes and wanes (this is the "wavy" sound heard in the hypnotic sessions) as the two stereo sounds mesh in and out of phase. The binaural beat is perceived as a fluctuating rhythm at the frequency of the difference between the two auditory inputs.

 

Binaural beats can easily be heard at the low frequencies (< 30 Hz) that are characteristic of the EEG spectrum (Oster, 1973). This perceptual phenomenon of binaural beating and the objective measurement of the frequency-following response (Hink, Kodera, Yamada, Kaga, & Suzuki, 1980) suggest conditions which generate brain waves activity and altered states of consciousness (hypnotic trance).

There are a growing amount of research efforts reporting changes in consciousness associated with binaural-beats. "The subjective effect of listening to binaural beats may be relaxing or stimulating, depending on the frequency of the binaural-beat stimulation" (Owens & Atwater, 1995). Binaural beats in the delta (1 to 4 Hz) and theta (4 to 8 Hz) ranges have been associated with reports of relaxed, meditative, and creative states (Hiew, 1995), and used as an aid to falling asleep. Binaural beats in the alpha frequencies (8 to 12 Hz) have increased alpha brain waves (Foster, 1990) and binaural beats in the beta frequencies (typically 16 to 24 Hz) have been associated with reports of increased concentration or alertness (Monroe, 1985) and improved memory (Kennerly, 1994).Mind-Fit uses the differing rates of Binaural beat stimulation during the induction and therapy parts of its sessions to aid in the progressive relaxation acquired when entering the Hypnotic state.

Binaural beats can be heard within a music track because each channel has been altered to produce a sound with a difference reflecting the desired frequency. Following is a sample to show you the effect. First you will hear 20 seconds of a peice of music, followed by the same peice encoded with binuaral beats. You should hear a slight wavey sound effect.

Click the image to play the sound