Brainwave activity during meditation
The brain is made up of billions of cells called neurons. They use electricity to communicate with each other. The electrical activity of the brain has a wave-like nature, called brainwave pattern. The mind regulates its activities by means of electrical waves in the brain, emitting electrochemical impulses of varied frequencies, which can be registered by an electroencephalogram. During meditation, the brainwaves change.
These brainwaves changes are as follows—
- Beta waves—The frequency ranges from 13 to 60 pulses per second on the Hertz scale. They are emitted when we are consciously alert, agitated, tense or afraid. In general, we are accustomed to using this frequency. They awaken awareness, extroversion, concentration, logical thinking, and active conversation.
- Alpha wave—Its frequency is around 7 to 13 pulses per second. They occur in a state of physical and mental relaxation. When we decrease the brain rhythm to alpha, we create conditions that are ideal to learn new information and data, perform elaborate tasks and analyze complex situations. They place the brain in states of relaxation, non-arousal, meditation and hypnosis.
- Theta wave—They have a frequency of 4 to 7 pulses. They occur in states of somnolence and deep meditation. They are found in day dreaming, dreaming, mental imagery, creativity, meditation, paranormal phenomena, out of body experiences, ESP or shamanic journeys. A person driving on a freeway, who discovers that they can't recall the last five miles, is often in a theta state, which is 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 in which a person is so deeply immersed in the performance of a task that he loses a sense of time. The ideation that can take place during the theta state is often free flow. It is typically a very positive mental state.
- Delta waves—They have a frequency of 0.1 to 4 pulses per second. They occur when there is unconsciousness, deep sleep, catalepsy or deepest meditation.
There are basically two types of meditations – directive meditation, where a person tries to concentrate on a particular object like a thought, a mantra or a visual form and non-directive meditation, where a person merely observes the thoughts crossing the mind without a reaction.
In advanced meditators, there is increased activity in the left prefrontal cortex. The changes are stable over time. If one stops meditating for a while, the effect lingers. In advanced meditators, theta waves are most abundant in the frontal and middle parts of the brain, which originate from a deep relaxation. It has also been found that an advanced meditator is able to voluntarily make a continuous transition between the various types of brain waves during deep meditation, suggesting that his brain is capable of voluntarily shifting between brain waves and their associated mental states.
There is little delta wave activity during meditative tasks, confirming that non-directive meditation is different from sleep. There is also little beta wave activity during meditation. There is a better relaxation and stress management by meditation techniques, when a practitioner refrains from controlling the content of the mind, as in non-directive meditation. The non-directive meditation allows the spontaneous wandering of the mind without getting too much involved. Instead one lets thoughts and emotions pass by in an effortless way.
So, during non-directive meditation, a practitioner experiences marked changes in electrical brain wave activity associated with wakeful, relaxed attention than just rest and relaxation.
It has been found that in some meditators the brain wave activity speeds up rather than slow down, approaching frequencies in the beta range in deep meditative states. These frequencies are usually associated with heightened alertness and complex cognitive thought processes, which suggest that a form of "focused arousal" might characterize these states. In these states, the brain can use existing knowledge and skills to address an unanswered question or troubling situation. Therefore, regular meditation promotes cognitive development which refers to how a person perceives, thinks and understands his or her world through interaction of genetic and learned factors.
The neurons in the brain communicate with each other by means of electric activity called brainwaves, which can be registered by an electroencephalogram. Meditation can strongly influence the frequency and pattern of these brainwaves. During meditation, the frequency of the brainwaves is reduced depending on the depth of meditation in an individual.
An expert meditator can easily make a transition from alpha to theta to delta state and, therefore, voluntarily change the level of meditation.