Nov 23, 2010 Learning Methodology 3013 Views
The brain is powered by electromagnetic energy. Whether we are mentally active, resting or asleep, the brain always has electrical activity. Researchers have speculated that a fully functioning brain can produce as much as 10 watts of electrical power. Even though this electrical power is limited, by attaching electrodes to the scalp and using an electroencephalogram (EEG), we can view and analyze the traces of electrical activity that represent the brainwaves. Like all waves, brain waves have a frequency, which are measured in cycles per second or Hertz (Hz); the lower the Hz, the slower the wave. Brain waves are classified by frequency and there are four categories. 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.
BETA WAVES (15 to 40 cycles per second)
When the brain is aroused and active, it produces beta waves. These beta waves are of low amplitude and are the fastest of the four brainwaves. Beta waves are characteristics of an active mind. They are present when one is fully engaged, aware, concentrating, thinking logically and in active conversation. A person making a speech or teaching would be in beta. On the negative side, these brainwaves predominate during times of stress and with feelings of paranoia, worry, fear, and anxiety. They are also present with hunger, depression, irritability, and moodiness. Insomnia is believed to be the result of producing excessive beta brainwaves. Beta waves are also associated with excessive inner chatter and self-destructive impulses. It has been shown that too much time in the beta state weakens the immune system
ALPHA WAVES (7-14 cycles per second)
Where beta waves represented arousal, alpha waves represent less arousal. Alpha brainwaves are slower and higher in amplitude. The alpha rhythm is most evident when one is awake, with eyes closed and relaxed. Alpha waves are characterized by relaxed wakefulness where creative thought and the behavioral efficiency of routine behaviors are optimal. A person who takes time to reflect or meditate is usually in an alpha state. The alpha rhythm decreases or disappears when one is mentally concentrating, physically moving or becoming apprehensive. Some researchers have hypothesized the alpha rhythm to be a possible physiological correlate of the hypnotic state. They have found evidence of hypnotic susceptibility being positively correlated with higher levels of waking alpha production.
There are differences in the alpha rhythm during meditation as well. As one meditates, the alpha waves gradually spread from the occipital to the frontal areas of the brain. During the second stage of meditation, theta waves appear and move from frontal to posterior parts of the brain. A third stage, which is seen in only the most experienced meditator, is characterized by more beta waves, which are present over most of the scalp.
THETA WAVES (4-7 cycles per second)
Theta waves have greater amplitude and slower frequency than alpha waves and are associated with the early stages of sleep and dreaming. Thetabrainwaves are present for about 60% of sleep and are also present during the barely conscious state just before sleeping and just after waking. The brain also produces theta waves during the Rapid Eye Movement (REM) part of the sleep cycle. If one is quiet and slows their mind down during Alpha, they will naturally go into theta.
A theta state will develop when tasks become so automatic that one can mentally detach from them. For example, one is in a theta state when driving on a freeway with little traffic. The repetitive nature of this form of driving would result in a theta state compared with driving in heavy traffic where a beta state would be produced to perform the driving task safely. Individuals who do a lot of freeway driving often get good ideas during those periods while they are in theta. Individuals who run regularly are often in a brainwave state that is slower than alpha and when in theta, they are prone to a flow of ideas. Ideas that take place during the theta state are often free flow and are experienced as a positive mental state.
Theta brain waves are connected with subconscious processing. This is where long-term memories and experiences, creativity, deep spiritual connection and any emotional memories are kept. Researchers discovered that during deep meditation, theta brainwaves are increased. Theta waves are also more plentiful with deeper levels of meditation. They also found that the feelings of serenity, bliss and higher consciousness, which people seek from meditation are only achievable, when theta brainwaves are dominant. Most researchers believe that it is possible to hasten by many years the time needed to achieve high levels of meditation by using brainwave entrainment.
After Training in in meditation for eight weeks, subjects show a pronounced change in brainwave patterns,shifting from alpha waves of aroused, conscious thought to the theta waves that dominate during periods of deep meditation.
Theta waves are present during powerful surges of emotion. People have much stronger emotions, whether happy or sad, while in the theta Range. Theta waves have also been linked to intuition. It has been shown that theta waves are present with instinctive "feelings" in the pit of your stomach. While in the theta state, the mind is capable of deep and profound learning, healing, and growth.
Theta waves have been associated with improved creativity, deeper relaxation, daydreaming, and dreaming while asleep. People with more theta wave activity think more creatively than those with less activity. Musicians, painters and designers have more theta waves than average. It has also been found that people with lower levels of anxiety, stress, and neurosis have stable theta brainwave activity.
On the more negative side, theta waves may be the dominate brain wave activity when one is having difficulty concentrating. People with attention-deficit problems (ADD) cannot shift out of the Theta State when events that need focus, such as taking a test, arise.
DELTA WAVES (1.5 to 4 cycles per second)
Delta waves have the greatest amplitude and slowest frequency of the brainwaves. They typically range from 1.5 to 4 cycles per second. Brain waves are rarely lower than 1.5 Hz; zero would suggest no activity in the brain or in other words, brain death. Delta waves are the deepest level of dreamless sleep (2 to 3 Hz), in which, our bodies shut down to focus on healing and growing. Practiced meditators can achieve this state of consciousness while awake.
Delta brainwaves are conducive to healing (the immune system is strengthened), rejuvenation, divine knowledge and personal growth. Peak performers decrease delta waves when high focus and peak performance are required. However, most individuals diagnosed with Attention Deficit Disorder (ADD) naturally increase rather than decrease delta activity when trying to focus. The inappropriate delta response often severely restricts their capacity to focus and preserve attention.
To understand delta waves, it is helpful to review what is known about sleep patterns. Typically, before sleep, one is in low beta. When the lights go off and the eyes are closed, the sleep cycle begins. The first stage of sleep is characterized by theta waves. As the sleeper moves to stage 2 sleep, theta wave activity increases. Stages 1 and 2 are "light" stages of sleep. In fact, if someone is awoken during one of these stages, he or she will often report not being asleep at all. The theta waves of stage 1 and 2 change to the delta waives of stage 3 and 4. There is no real division between stages 3 and 4 except that in stage 3 less than 50 percent of the waves are delta, while in stage 4 greater than 50 percent are delta. With these four basic stages of sleep, there is the unique stage of rapid eye movements (REM). This stage is associated with a unique combination of alpha, beta, and desynchronous (the waves are not consistent in their pattern) brainwaves (see Figure 1). This is the stage of sleep where dreaming occurs.
A normal night's sleep begins in stage 1 and moves through the stages to stage 4. The cycle then repeats, except that stage 1 is replaced by REM. One cycle, from stage 1 to REM takes about ninety minutes. This cycle is repeated throughout the night. When the awakening process begins, the brainwaves will increase from delta to theta and then to alpha and finally, when the alarm goes off, into beta. During this awakening cycle it is possible for individuals to stay in the theta state for five to 15 minutes, this time can be productive of meaningful and creative thoughts.