Biology - Brain: Brain Activity During Meditation

The brain is an electrochemical organ - using electromagnetic energy to function. Electrical activity emanating from the brain is displayed in the form of brainwaves.

 

 

There are four categories of these brainwaves. They range from the high amplitude, low frequency delta to the low amplitude, high frequency beta. Men, women and children of all ages experience the same characteristic brainwaves. They are consistent across cultures and country boundaries.

During meditation brain waves alter.

• BETA - 13-30 cycles per second - awaking awareness, extroversion, concentration, logical thinking - active conversation. A debater would be in high beta. A person making a speech, or a teacher, or a talk show host would all be in beta when they are engaged in their work.
   
• ALPHA - 7-13 cycles per second - relaxation times, non-arousal, meditation, hypnosis
   
• THETA - 4-7 cycles per second - day dreaming, dreaming, creativity, meditation, paranormal phenomena, out of body experiences, ESP, shamanic journeys.

A person who is driving on a freeway, and discovers that they can’t recall the last five miles, is often in a theta state - induced by the process of freeway driving. This can also occur in the shower or tub or even while shaving or brushing your hair. It is a state where tasks become so automatic that you can mentally disengage from them. The ideation that can take place during the theta state is often free flow and occurs without censorship or guilt. It is typically a very positive mental state.

• DELTA - 1.5-4 or less cycles per second - deep dreamless sleep

Link: http://www.bibliotecapleyades.net/ciencia/ciencia_brain01.htm