Brain waves are generated by the building blocks of your brain

The individual cells are called neurons. Neurons communicate with each other by electrical changes. We can actually see these electrical changes in the form of brain waves as shown in an EEG (electroencephalogram).

Brain waves are measured in cycles per second (Hertz; Hz is the short form). We also talk about the "frequency" of brain wave activity.

The lower the number of Hz, the slower the brain activity or the slower the frequency
of the activity. They can be "seen" with an electroencephalograph (EEG).

Brainwave patterns are commonly grouped into four different categories: Beta, Alpha, Theta and Delta.

Each of these brainwave patterns are associated with various states of mind.

Beta (14-30 Hz)	Alpha (8-13.9 Hz)
Concentration, arousal, alertness, cognition Higher levels associated with anxiety, unease, feelings of separation, fight or flight	Relaxation, superlearning, relaxed focus, light trance, increased serontonin production Pre-sleep, pre-waking drowsiness, meditation, beginning of access to unconscious mind
Theta (4-7.9 Hz)	Delta (.1-3.9 Hz)
Dreaming sleep (REM sleep) Increased production of catecholamines (vital for learning and memory), increased creativity Integrative, emotional experiences, potential change in behavior, increased retention of learned material Hypnagogic imagery, trance, deep meditation, access to unconscious mind	Dreamless sleep Human growth hormone released Deep, trance-like, non-physical state, loss of body awareness Access to unconscious and "collective unconscious" mind,

 

Other types of brainwaves have now been identified.

• The Sensory motor rhythm (or SMR; around 14 hz)
      SMR activity seems to link brain and body functions.

• Gamma brain waves (39-100 hz) are involved in higher mental activity and consolidation of information.

Higher-than Beta frequencies are called Gamma. These Gamma brainwaves resonate around 40 Hz and are associated with the brain function which holographically synthesizes all the bits of individual data from various areas of the brain and fuses them all together in a higher perspective.

Gamma is a 'newer' brainwave only because it is difficult to get instrumentation to accurately measure it. It is thought the Gamma is the harmonizing frequency - for example when you are observing an object, its colour, size, texture etc are all perceived and processed by different parts of the brain, it is thought that Gamma allows for unification of all the different information.

This brainwave activity is associated with states of self awareness, higher levels of insight and information, psychic abilities and out of body experiences.

An interesting study has shown that advanced Tibetan meditators produce higher levels of gamma than non-meditators both before and during meditation.