What are Beta Waves?
When you are fully awake and alert, your brain generates beta waves. Conscious thinking; analyzing, planning, solving equations, balancing accounting sheets, writing articles, designing a house and all thinking done when you are fully awake and alert generates beta waves in your brain.
The frequency of beta waves range from 13hz to 38hz. Audible frequencies range from 20hz to 20000hz but some people can hear sounds down to 16hz. If the beta waves that fall within this range are strong enough, we would be able to hear them but the signals are so small that it would be far from audible to the human ear.
Below is a beta wave illustration taken from an EEG(electroencephalograph). It depicts the highs and lows of beta waves for a duration of 1 second.
This brainwave pattern indicates that there are more highs and lows for a given time period compared to the alpha, delta and theta states. There is also another set of brainwave frequencies higher than beta called the gamma waves which have higher frequencies or highs and lows.
Different frequencies within the beta frequency range are associated with different states of mind. There are those which can increase your focus and attention, those which can increase stress, those which can make you agitated, and many other. There are many techniques to entrain the brain to a particular frequency and make it dominant making the body follow along the characteristics of the specific brainwave frequency: be it releasing hormones, twitching muscles, intensity of concentration, etc..
Isochronic tones, binaural beats and monaural beats are some techniques used for brainwave entrainment. Of the three techniques mentioned, isochronic tones were able to achieve better results.
The beta state is where you interact with the physical world. It's the pattern of your brainwaves when you are jogging, making decisions, or just plain thinking when you are awake.