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Meditation has been known and practiced for a long period of time. Presently, its practice is being advocated and promoted mainly as an effective remedial measure against the deleterious effects of challenges and stress of modern life. However, the unambiguous identification of attainment of meditation-state has yet to be established. Meditation is known to be associated with alterations in neurochemistry and neurophysiology that are responsible for diverse experiences observed in meditators. This brief paper attempts to highlight the significance of EEG in meditation and consequently recommend it as an appropriate and invaluable tool in determining the attainment of meditation-state.
Despite its popularity worldwide, the basic features of meditation, like definition and identification of meditation-state continue to be elusive and a consensus on these fundamental issues is yet to be reached. Although, an operational definition has been presented recently [1], the attainment of a true meditation-state remains controversial and its identification on scientific grounds continues to be not only challenging and deceptive, but is further confounded by finding meditators in sleep during the process of meditation (as assessed by EEG recording and reported by some researchers) [2-3]. This has led to many practitioners claiming to attain the meditation-state, but such subjective claims could be dubious and unacceptable on scientific grounds. Trainers or educators of meditation also may find themselves helpless in objective determination of attainment of the meditation-state in their subjects unambiguously.Meditation is recognized as a definite state of mind apart from the other three states i.e. wake, sleep and hypnosis and therefore, its identification needs to be clearly defined. This brief paper attempts to demonstrate the scientific means of identifying the attainment of meditation-state.
Meditation is associated with release of several neurochemicals especially glutamate, dopamine, opioids and serotonin [4]. However, identifying the attainment of meditation-state by the continuous monitoring of their levels in meditators during its practice may not be feasible especially in keeping with the possibility of mis-interpretation of their levels, which can fluctuate widely under several influences, both external and internal.Meditation is generally viewed as a state of mind with pure, uncontaminated and unrestricted free flow of thoughts, which are also believed to occur during automatic reflex activities like bathing and dressing. This state of free flow of thoughts has been found to correspond with diffuse or generalized theta activity in the EEG. It is during this period that many ideas have been generated and complex problems solved; âEurekaâ exclamation by Archimedes while bathing in a tub of water is a well-known unforgettable example on arrival at a solution.Meditation is associated with silencing of previously active brain areas and activation of pacified areas, thus creating a widespread cortical area of a general-state activation. During meditation, researchers have observed diffuse theta-bursts, during which the practitioners experience peace, calmness and pleasure [5-6]. Mystic, divine and spiritual experiences are also claimed and believed to occur during this state.The ecstatic feelings or experiences set up strong motivations and desires for continued meditational practice. Increased theta power in EEG spectrum has also been found to correlate with increased endogenous dopamine release [7], which plays a crucial role in reward motivations and drives.Neuroimaging techniques like functional magnetic resonance imaging (fMRI) to study brain areas of activation do not offer a convenient mode of investigation mainly on account of disturbance and distraction caused during meditation. EEG recording is a valuable and reliable tool to detect the theta spectrum and its cortical distribution and therefore, it is recommended that this simple non-invasive neuro-technique may be utilized as a reliable scientific means in identifying the attainment of the meditation-state.
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