Background

• Various forms of meditation have been practiced for thousands of years throughout the world, with many techniques originating in spiritual traditions, particularly in Eastern philosophical and religious practices. In modern times, numerous meditation types are in use, often outside of their original religious and cultural contexts.
• The definition of meditation is variable. A classic definition of meditation is the deliberate self-regulation of attention through which the stream of consciousness is temporarily suspended. A common goal is to attain a state of "thoughtless awareness" of sensations and mental activities occurring at the present moment. However, meditation is often popularly perceived as any activity through which a person's attention is focused on a repetitious thought or word. Meditation generally does not involve suggestion, autosuggestion, or trance. Techniques that make use of constant repetition of syllables, visualizations, or other thought forms, but do not achieve thoughtless awareness are sometimes described as being "quasi-meditative." There are many forms and sub-types of meditation or "quasi meditation," and several techniques are described below.
• Mindfulness is an approach in which attention is focused on a physical sensation (such as the breath). When thoughts intrude, the individual returns to the focus. Attention is placed on the present moment, rather than on the future or past. This technique may involve a "body scan," in which one focuses on the body from head to feet, concentrating on areas of pain or illness. This is usually performed while lying down. Regular practice is suggested to enhance self-awareness.
• Analytical meditation differs from other forms in that the practitioner does not repeat a word over and over, but rather strives to comprehend the deeper meaning of the object of focus. Guided meditation or guided imagery is a technique that directs the imagination towards a conscious goal. Yoga nidra or yogic "sleep" is considered to be a form of guided meditation.
• Breath meditation involves focusing on the process of inhaling and exhaling. Deep breathing exercises taught in childbirth classes are a variation of this form. Counting while breathing may provide a meditative focus.
• Visualization involves focusing on a specific place or situation. Walking meditation or kinhin is a Zen Buddhist form of movement meditation in which attention is focused on the feeling of the earth beneath the feet. Sitting meditation is similarly practiced. "Naming" consists of giving a name to physical sensations associated with particular emotions in order to become more self-aware. Numerous other variations and subtypes of meditation exist. Meditation is traditionally distinguished from relaxation based on the state of thoughtless awareness that is said to occur during meditation.
• Meditation is generally practiced in a quiet environment and in a comfortable position. Sessions vary in length and in number of times practiced daily. It is often recommended to meditate at the same time(s) each day.
• Some organized religions and professional organizations have their own specific requirements for formal training and explicit credentialing for new teachers. There are several recognized certification programs for meditation instructors. Widely accepted credentialing and licensure for meditation instructors, however, are currently lacking.
• Transcendental meditation® (TM®): TM® is a controversial practice that involves the technique of focusing on a "mantra" (a sound, word, or phrase that is repeated to oneself over and over, either aloud as a chant, or silently). Maharishi Mahesh Yogi, who became well known due to famous followers such as the musical group The Beatles, introduced TM® to the West in the late 1950s. A goal of TM® is to reach a state of consciousness that is beyond wakefulness, sleep, or dreaming, in which relaxed awareness is achieved. When thoughts intrude, they may be noticed passively before returning to the mantra. Some practitioners suggest that when meditating individuals attain a state of "pure consciousness," they can influence the emotions or mental states of people around them. This area has not been scientifically evaluated. Other claimed benefits of TM® are also controversial, such as improved IQ, reduced violent tendencies, and "yogic flying." It has been argued as to whether TM® should be classified as a religion or not, and some have asserted that TM® constitutes a cult or religious sect. TM® is a registered trademark with centralized administration of training at program centers worldwide.

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