Alteration of brainwave pattern as a result of meditation is a popular avenue for brain research because the results can be observed and measured. Although the brain waves cannot be considered to be associated with any specific state of mind, there are some interesting correlates of the findings that might increase our understanding how meditation works.
What does the technique of meditation do which simple relaxation with eyes closed cannot? A recent study conducted jointly by the University of Sydney and the Norwegian University of science and technology (NTNU) was set up specifically to answer this question. In particular, the 4 major brainwaves– Alpha, beta, gamma and theta were studied by analysing electrical activity recordable from the brain by a technique called the electroencephalogram (the same technique that is used to diagnose epilepsy through analysing disordered brain waves).
This study have confirmed the findings of the earlier studies that meditation increases both the alpha and theta activity of our brain.
In simplified terms, alpha activity of the brain denotes relaxation by any means, be it meditation or any other form of relaxation and rest as we take a break from our daily work routines. However, the mind never goes the rest in the state, instead it shifts to mode of background processing as thoughts images and memories appear spontaneously from within. Experienced meditators become aware of this spontaneous wandering of the mind. The importance of alpha activity perhaps lies in giving us a break from our hectic schedules and allowing your minds to put emotional and life events in proper perspective. Neurologically, it is perhaps best described as a state of wakeful rest.
By contrast, theta activity of the brain is the signature hallmark of meditation. It is recorded of most abundantly from the frontal and middle lobes of the brain and is thought to originate from a relaxed mode of monitoring our inner feelings and experiences. In highly experienced meditators, it indicates a deliberately induced state of mental calm, as these practitioners experience a sense of both physical and mental quietude–associated with the frontal parts of the brain monitoring overall mental processes in all parts of the brain. In different traditions of meditations this state has been referred to as the supra–consciousness or total mindfulness. This state however requires training in specific modes of meditative practice, and does not arise with simple relaxation techniques.
Sleep is recognised on the electroencephalogram (EEG) by the presence of Delta waves, which are characteristically absent in meditation and simple relaxation. Thus sleep has a very different role in our life from meditation or induced states of relaxation.
Beta waves, seem typically when we’re focusing on goal directed tasks is absent during both meditation and resting, and is therefore a hallmark of problem-solving activities that dominate our lives when we are constantly engaged in doing something.[In the next article we would discuss the difference between concentration as a meditative technique versus nondirective meditation where we refrain from trying to control the content of the mind.]
Lagopoulos et al. Increased Theta and Alpha EEG Activity During Nondirective Meditation. The Journal of Alternative and Complementary Medicine, 2009; 15 (11): 1187 DOI: 10.1089/acm.2009.0113
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