Brainwaves
Brainwaves are the fingerprints of the state of the mind. When we are relaxed and awake, the brainwaves in the alpha region of 8-14 Hz are dominant. As we go into high thinking mode, the frequencies increase and the brain will be dominated by beta waves, 14-30 Hz. On the other hand, lower frequency brainwaves reflect lower levels of brain activity; for example, the state of drowsiness is represented by 4-8 Hz waves and the deep sleep by waves lower than 4 Hz. These waves can be easily recorded by electroencephalography (EEG) over the scalp.
Brainwaves entrainment
Brainwaves have a tendency to resonate with external stimuli such as sounds (or lights) of certain frequencies. This phenomenon is known as frequency following response or entrainment. This fascinating concept has been gainfully used to take the brain to any desired state such as states of deep relaxation or meditation, by sending in the desired frequency waves.
For instance, if a person is in the mentally active beta state and if a stimulus of 10 Hz is applied, the brain frequency is likely to slowly shift towards 10 Hz. It will have a relaxing effect on the person.
When the stimulus is close to the current dominant brain state, entrainment works better. Hence, the starting applied frequency is kept as close to the current brainwaves state as possible. Although it is not possible to determine the current brain state without an EEG recording, but it can be safely assume that the brainwaves are around 20 Hz during the waking hours of the day. So one can begin entraining from there. However, if the person is already relaxed, he can start from 15 Hz or lower.
Creation of binaural beats
Now the question is how to apply these frequencies? Human ear is not sensitive to frequencies below 20 Hz. So some special technique is required. One popular way is creation of binaural beats. It involves feeding two slightly different frequencies, one to each ear. The difference frequency is perceived in the brain as a warbling sound; these cyclic pulsations are called binaural beats. For example, if you transmit a steady tone of 300 Hz to the left ear and 310 Hz to the right ear, the brain perceives it as a 10 Hz beats.
These beats are possible only within a small range of input frequency differences. If the two frequencies match, the beats disappear and if they differ by more than 30 Hz, they are heard as two different notes. If each frequency is played individually, you will hear them normally, but if played together, you sense the pulsation (binaural beats). So the phenomenon is not acoustic but happens in the brain. For reasons of the physics of sound waves related to human acoustic system, you must use the input frequencies below 1000 Hz.
Binaural beats music
You must also note that mere passive listening to binaural beats may not always alter the state of your consciousness – your ability and willingness to relax and focus attention play important role in determining how effective the binaural beats work on you. Listening to pure binaural beats may not be appealing to most people, so they are often mixed into other interesting sounds like that of waterfall, flowing river, rain, gongs, etc. In most cases, these sounds completely mask the binaural beats so the listener is completely unaware of them, but the brain, of course, registers them.
So, you have music that not just entertains your ears but that also entrains your brain. You can use it to explore and discover the latent potentials of your mind in the easiest possible way.
