Five broad categories of meditation practices were identified:

• – Mantra meditation,
• – Mindfulness meditation,
• – Yoga,
• – Tai Chi, and
• – Qi Gong.

• • Characterization of the universal or supplemental components of meditation practices was precluded by the theoretical and terminological heterogeneity among practices. Evidence on the state of research in meditation practices was provided in 813 predominantly poor-quality studies.

The three most studied conditions were hypertension, other cardiovascular diseases, and substance abuse. Sixty-five intervention studies examined the therapeutic effect of meditation practices for these conditions. Meta-analyses based on low-quality studies and small numbers of hypertensive participants showed that TM®, Qi Gong and Zen Buddhist meditation significantly reduced blood pressure.

Yoga helped reduce stress. Yoga was no better than Mindfulness-based Stress Reduction at reducing anxiety in patients with cardiovascular diseases. No results from substance abuse studies could be combined. The role of effect modifiers in meditation practices has been neglected in the scientific literature. The physiological and neuropsychological effects of meditation practices have been evaluated in 312 poor-quality studies. Meta-analyses of results from 55 studies indicated that some meditation practices produced significant changes in healthy participants.

The interest in meditation practices as healing strategies comes with the need to acquire a deeper knowledge of the intricate connections between body and mind, and how the mental and spiritual state of an individual directly affects psychological and physical well-being. Meditation practices have been advocated as mind-body treatments for health-related problems and as methods to attain or maintain general wellness. There is a growing body of scientific literature on the effects of meditation practices for a variety of psychiatric disorders such as depression, anxiety, panic disorders, binge eating disorders, and substance abuse among others. Effects of meditation practices have been also documented using measures of emotional distress20 and cognitive abilities.

The effects of meditation practices as complementary treatments for medical conditions other than mental illness have been evaluated using a variety of methods and outcomes. These clinical conditions include hypertension24 and other cardiovascular disorders, pain syndromes and musculoskeletal diseases, respiratory disorders (e.g., asthma, congestive obstructive pulmonary disease),29 dermatological problems (e.g., psoriasis, allergies),30 immunological disorders, and treatment-related symptoms of breast and prostate cancer.

There is also a considerable interest in understanding the physiological and neuropsychological effects of certain meditation practices. Research conducted in this area has used a variety of methodological approaches and formal evaluations of the methodological quality of this body of evidence have not been conducted.

The main components of any meditation practice or technique refer to its most general features. These may include specific postures (including the position of the eyes and tongue), the use of a mantra, breathing, a focus of attention, and an accompanying belief system. Posture refers to the position of the body assumed for the purpose of meditation. Though traditional meditation practices prescribe particular postures (e.g., the lotus position), postures vary between practices with the only limitation being that the posture does not encourage sleep. Because accounts of most meditation practices describe explicitly the use and role of breathing, mantra, attention, spirituality and belief, training, and criteria for successful meditation practice, these topics are described individually.

Breathing. Breathing in meditation can be incorporated passively or actively. In passive breathing, no conscious control is exerted over inhalation and exhalation and breathing is “natural.” In contrast, active breathing involves the conscious control over inhalation and exhalation. This may involve controlling the way in which air is drawn in (e.g., through the mouth or nostrils), the rate (e.g., drawn in quickly or over a specified length of time), the depth (e.g., shallow or deep), and the control of other body parts (e.g., relaxation of the abdomen).

Mantra. A distinctive feature of some meditation practices is the use of a mantra. A mantra is a sound, word, or phrase that is recited repetitively, usually in an unvarying tone, and used as an object of concentration. The mantra may be chanted aloud, or recited silently. Mantras can be associated with particular historical or archetypal figures from spiritual or religious systems, or they may have no such associations.

Relaxation. Relaxation is often considered to be one of the defining characteristics of meditation practices and meditation itself is often considered to be a relaxation technique.66-68 Indeed, it has been suggested that the popularity of meditation practices in the West is due, at least in part, to the widely accepted plausibility of their alleged effects with respect to arousal reduction.69 Some researchers have attempted to draw a distinction between relaxation and meditation practices on the basis of intention.

Attention and its object. The intentional self-regulation of attention is considered crucial to the practice of meditation, as is the development of an awareness in which thoughts do not necessarily disappear, but are simply not encouraged by dwelling on them, a state of so-called “thoughtless awareness.

“Mindfulness” meditation techniques aim to cultivate an objective openness to whatever comes into awareness (e.g., by paying attention to simple and repetitive activities or to the sensations of the body). In doing so, the breath may be used as an anchor (but not a focal point) to keep the meditator engaged with the present moment. Each of these techniques serves, in a different way, to discourage logical and conceptual thinking.

Spirituality and belief. This component refers to the extent to which spirituality and belief systems are a part of meditation practices. Spirituality and belief systems are composed of metaphysical concepts and the rules or guidelines for behavior (e.g., devotional practices or interpersonal relations) that are based on these concepts.

Training. Training refers to the recommended frequency and duration of periods of practice, and how long a practitioner is expected to train before being considered proficient in a given technique.

Criteria of successful meditation practice. The criteria of successful meditation practice are understood both in terms of the successful practice of a specific technique (i.e., is the technique being practiced properly) and in terms of achieving the aim of the meditation practice (e.g., has practice led to reduced stress, calmness of mind, or spiritual enlightenment).

Five broad categories of meditation practices were identified in the scientific literature: mantra meditation (comprising Transcendental Meditation® [TM®], Relaxation Response [RR], and Clinically Stadardized Meditation [CSM]), mindfulness meditation (comprising Vipassana, Zen Buddhist meditation, Mindfulness-based Stress Reduction [MBSR], and Mindfulness-based Cognitive Therapy [MBCT]), Yoga, Tai Chi, and Qi Gong. These broad categories were used for descriptive purposes throughout the report to address the key research questions.

Mantra Meditation

The distinctive characteristic of the meditation practices included in this category is the use of a mantra. A mantra is a word or phrase repeated aloud or silently and used to focus attention. A mantra often has a smooth sound, for example, the mantras “Om” or “Mu.” It is thought that these sounds produce vibrations that have different effects on people, and these vibrations can be described qualitatively or quantitatively. The three mantra meditation practices described below consist of standardized techniques; that is, the techniques have been described systematically in manuals and are relatively invariant wherever, whenever, and by whomever they are taught.

Transcendental Meditation®

TM® is a technique derived from the Vedic tradition of India by Maharishi Mahesh Yogi. In TM®, a meditative state is purportedly achieved in which the repetition of the mantra no longer consciously occurs and instead the mind is quiet and without thought. During the practice of TM®, the ordinary thinking process is said to be “transcended” (or gone beyond) as the awareness gradually settles down and is eventually freed of all mental content, remaining silently awake within itself, and producing a psychophysiological state of “restful alertness.” These periods, referred to as pure consciousness or transcendental consciousness, are said to be characterized by the experience of perfect stillness, rest, stability, order, and by a complete absence of mental boundaries.

Main components. In the TM® technique, the meditation state is achieved by the repetition of a mantra. The mantra is a meaningless sound from the ancient Vedic tradition and is given to the meditator by an instructor in the TM® technique. TM® practitioners sit in a comfortable posture, with eyes closed, and silently repeat the mantra. Though there are reports of the components of the mantras and how they are assigned, it is difficult to confirm these reports as many of the details of practice, including mantras, are revealed only to those who have formal instruction in TM®. Instruction in the TM® technique is a systematic, but individualized process. It is believed that keeping the techniques confidential prevents students from having preconceptions about the technique (making the learning process simpler) and that it maintains the integrity of the technique across generations.

Breathing. TM® involves passive breathing; no breath control procedures are employed and no specific pattern is prescribed.

Attention and its object. TM® is described as not requiring any strenuous effort, concentration, or contemplation. However, meditators are instructed to direct their attention to the mantra.

Spirituality and belief. The TM® technique has a theoretical framework that is described in Maharishi Mahesh Yogi’s writings on the nature of transcendental consciousness and the principles underlying the TM® technique.81 However, it is unclear to what extent this theoretical framework, including any of its implications for spirituality, is a part of the practice. Sources that discuss this issue contend that the practice of the technique requires no changes in beliefs, philosophy, religion, or lifestyle, implying that the theoretical framework plays no role in its practice.

Training. TM® is usually taught in a course comprising five to six hours of instruction over four days.

Mindfulness Meditation

Mindfulness has been described as a process of bringing a certain quality of attention to moment-by-moment experience and as a combination of the self-regulation of attention with an attitude of curiosity, openness, and acceptance toward one’s experiences.98 Mindfulness meditation, the core practice of Vipassana meditation, has been incorporated into several clinically-based meditation therapies.76 The capacity to evoke mindfulness is developed using various meditation techniques that originated in Buddhist spiritual practices;99 however, general descriptions of mindfulness vary from investigator to investigator and there is no consensus on the defining components or processes.

Mindfulness approaches are not considered relaxation or mood management techniques, and once learned, may be cultivated during many kinds of activities. Mindfulness increases the chances that any activity one is engaged in will result in an expanded perspective and understanding of oneself.76 In a state of mindfulness, thoughts and feelings are observed on par with objects of sensory awareness, and without reacting to them in an automatic, habitual way. Thus, mindfulness allows a person to respond to situations reflectively rather than impulsively.98 Mindfulness meditation practices include the traditional Vipassana, and Zen meditation and the clinically-based techniques MBSR and MBCT. Of the four practices described below, the last two, MBSR and MBCT have standardized techniques (i.e., the techniques have been described systematically in manuals and are relatively invariant wherever, whenever, and by whomever they are taught).

Clinically Standardized Meditation

CSM was developed by Patricia Carrington while she was conducting studies on meditation at Princeton University in the early-to-mid 1970s. Believing that TM® was not flexible enough to be suitable for all clinical purposes and that the cost of its instruction put it beyond the reach of most individuals and institutions, Carrington modified a classical Indian form of mantra meditation and produced what she called CSM.

Main components. Trainees are instructed to choose a mantra from a list of 16 Sanskrit mantras, or choose their own. In choosing their own mantra, practitioners are told to select a word that has a “pleasant ringing sound” and to avoid using words that are emotionally loaded. The word should help imbue the practitioner with a sense of serenity.64 In its original formulation, CSM used a secular ritual for transferring the mantra. CSM is practiced while sitting comfortably, with eyes open and focused on a pleasant object of some kind. The mantra is repeated aloud, slowly and rhythmically, at ever decreasing volume, until it is a whisper, at which point the mantra is no longer said aloud, but instead is only thought. The eyes are then closed as the meditator continues repeating the mantra in thought. Meditators allow the mantra to proceed at its own pace, getting faster or slower, louder or softer “as it wants.”

Breathing. Breathing is passive, proceeding at its own pace and is unconnected to the repetition of the mantra.

Attention and its object. Like TM® and RR, CSM is a passive technique that requires little concentration or discipline. In contrast to RR, CSM instructs practitioners to flow with their thoughts rather than ignore them, returning periodically to the mantra.

Spirituality and belief. CSM is designed as a secular, clinical form of meditation practice, so no specific system of spirituality or belief is required.

Training. CSM is taught in two lessons: a 1-hour individual lesson and a group meeting. CSM is practiced twice daily for 20 minutes. As with RR, the contemporary version of CSM differs slightly from its original form, with perhaps the most important difference being that trainees are given a manual and an audio recording of instructions rather than individual instruction.64

Criteria of successful meditation practice. The criteria for successful meditation practice rest with the subjective evaluation of the meditator, the results of practice judged against the reported effects of CSM. Books and audiotapes for self-instruction in CSM are readily available, and there is no explicit statement that an experienced practitioner teach the technique or that individualized instruction is necessary.

Main components. Vipassana meditation requires the cultivation of a particular attitude or approach: (1) don’t expect anything, (2) don’t strain; (3) don’t rush, (4) observe experience mindfully, that is, don’t cling to or reject anything, (5) loosen up and relax, (6) accept all experiences that you have, (7) be gentle with yourself and accept who you are, (8) question everything, (9) view all problems as challenges, (10) avoid deliberation, and (11) focus on similarities rather than differences.

Vipassana meditation is practiced in a seated position when focusing on the breath; otherwise, no posture is prescribed and the meditator may sit, stand, walk, or lie down. Traditionally, if a static position has been taken, it is not to be changed until the meditation session has ended. However, many Western teachers allow students to move, though mindfully, to avoid persistent pain caused by being in the same position for too long. The time devoted to seated meditation should be no longer than one can sit without excruciating pain. The eyes should be closed.

Breathing. Air is inhaled and exhaled freely through the nose. There is a natural, brief pause after inhaling and again after exhaling.

Zen Buddhist Meditation

Zen Buddhist meditation, or Zazen, perhaps one of the most well-known forms of meditation, is a school of Mahayana Buddhism103 that employs meditation techniques that originated in India several thousand years ago and were introduced to Japan from China in 1191 A.D.104 Zen Buddhist meditation is typically divided into the Rinzai and Soto schools.

Main components. The harmony of the body, the breath, and the mind is considered essential to the practice of Zen. In the traditional forms of Zen meditation, physical preparation involves eating nutritious food in modest amounts.104

Posture is of great importance in Zen meditation. In traditional forms, Zen meditation is performed while seated on a cushion in either the full-lotus or half-lotus position; however, many Western practitioners practice in a variety of ways from chair sitting to full lotus.104 In the full-lotus position, the legs are crossed and the feet rest on top of the thighs. In the half- lotus position, only one foot is brought to rest on top of the thigh, the other remaining on the ground as in the regular cross-legged position.104,105 The hands are held in one of two prescribed ways, either with the left hand placed palm up on the palm of the right hand with the tips of the thumbs touching, or with the right hand closed in a loose fist and enclosed in the left hand, the left thumb between the web of the thumb and the index finger of the right hand. The spine is held straight and with the top of the head thrust upward, with the chin drawn in and the shoulders and abdomen remain relaxed. The body should be perpendicular and the ears, shoulders, nose, and navel should be in line. The tongue should touch the upper jaw and the molars should be in gentle contact with one another. The eyes should be half closed and the gaze focused on a point on the floor approximately 3 feet in front.104,105

Breathing. Breathing in Zen meditation is active and many breathing patterns are used. One deep breathing pattern begins with exhaling completely through an open mouth and letting the lower abdomen relax. Air is then inhaled through the nose and allowed to fill the chest and then the abdomen. This breathing pattern is repeated 4 to 10 times. The mouth is then closed, and air is inhaled and exhaled through the nose only. By the use of abdominal and diaphragmatic pressures, air is drawn in and pushed out. Both inhalation and exhalation should be smooth, with long breaths.104 After practitioners have learned to focus on their breath by counting, counting is omitted and meditators practice “shikantaza,” which means “nothing but precisely sitting.” Shikantaza is the most advanced form of Zen meditation. With practice, the frequency of breathing becomes about three to six breaths per minute.

The MBSR program emerged in 1979 as a way to integrate Buddhist mindfulness meditation into mainstream clinical medicine and psychology.107 Originally designed by Dr. Jon Kabat-Zinn at the University of Massachusetts Medical Center, the MBSR program was a group-based program designed to treat patients with chronic pain. Since then, MBSR has also been used to reduce morbidities associated with chronic illnesses such as cancer and acquired immunodeficiency syndrome and to treat emotional and behavioral disorders.

Main components. The mindfulness component of the program incorporates three different practices: a sitting meditation, a body scan, and Hatha yoga. In addition to the mindfulness meditation practice that forms the basis of the intervention, patients are taught diaphragmatic breathing, coping strategies, assertiveness, and receive educational material about stress. The foundation for the practice of MBSR is the cultivation of seven attitudes:

1. nonjudgment, becoming an impartial witness to your own experience;
2. patience, allowing your experiences to unfold in their own time;

3. beginner’s mind, a willingness to see everything as if for the first time;
4. trust, in your own intuition and authority and being yourself;
5. nonstriving, having no goal other than meditation itself;
6. acceptance, of things as they actually are in the present moment; and
7. not censoring one’s thoughts and allowing them to come and go.48In addition to these attitudes, a strong motivation and perseverance are considered

essential to developing a strong meditation practice and a high degree of mindfulness.48 These attitudes are cultivated consciously during each meditation session.48 As with other mindfulness practices, posture and breathing are essential. The practitioner sits upright, either on a chair or cross-legged on the floor, and attempts to focus attention on a particular object, most commonly on the sensations of his or her own breath as it passes the opening of the nostrils or on the rising and falling of the abdomen or chest.48 Whenever attention wanders from the breath, the practitioner will simply notice the distracting thought and then let it go as attention is returned to the breath. This process is repeated each time that attention wanders from the breath. The MBSR program incorporates formal meditation (i.e., seated, walking, Yoga) and informal meditation (i.e., the application of mindfulness to the activities of daily life). In informal practice, practitioners are reminded to become mindful of their breath to help induce a state of physical relaxation, emotional calm, and insight.

The seated meditation is done either on the floor or on a straight-backed chair. When sitting on the floor, a cushion approximately 6 inches thick should be placed beneath the buttocks. The practitioner may use the “Burmese” posture in which one heel is drawn in close to the body and the other leg is draped in front, or a kneeling posture, placing the cushion between the feet.48 The sincerity of effort matters more than how one is sitting.48 Posture should be erect with the head, neck, and back aligned. The shoulders should be relaxed and the hands are usually rested on the knees or on the lap with the fingers of the left hand above the fingers of the right and the tips of the thumbs just touching each other.

Yoga

The philosophy and practice of Yoga date back to ancient times, originating perhaps as early as 5,000 to 8,000 years ago. It has been argued that the rules or precepts set down in the first systematic work on Yoga, Patanjali’s Yoga Sutras, do not set forth a philosophy, but are practical instructions for attaining certain psychological states. It is important to acknowledge the diversity of techniques subsumed under the term “Yoga.” Over many millenia, different yogic meditative techniques had been developed and used to restore and maintain health, and to elevate self-awareness and to also transcend ordinary states of consciousness, and ultimately to attain states of enlightenment.

Yogic meditative techniques have been transmitted through Kundalini yoga, Sahaja yoga, Hatha yoga and other yogic lineages. Though there are numerous styles of Yoga; the styles vary according to the emphasis and combination of four primary components: asanas, pranayamas, mantras, and the various meditation techniques. In Kundalini yoga, there are thousands of different postures, some dynamic and some static, and also thousands of different meditation techniques, many of which are disorder specific. Kundalini yoga meditation techniques are usually practiced while maintaining a straight spine, and employ a large number of specific, and highly structured breathing patterns, various eye and hand postures, and a wide variety of mantras. All of these techniques supposedly have different effects and benefits in their respective combinations.

Within Hatha yoga, many “schools” have developed, each differing slightly in its emphasis on the use of breathing and postures: in Bikram Yoga, practitioners perform the same sequence of 26 asanas in each session; in Vini Yoga, emphasis on the breath makes for a slower-paced practice. Iyengar Yoga is distinguished from other styles by its emphasis on precise structural alignment, the use of props, and sequencing of poses. There are also two Tibetan yogic practices, Tsa Lung and Trul Khor, that incorporate controlled breathing, visualization, mindfulness techniques, and postures.120 In Yoga, it is also believed that the practice of meditation techniques can be enhanced by the proper cleansing and conditioning of the body through the asanas and breathing exercises, or pranayama techniques (though pranayama places particular emphasis on techniques of breathing, some pranayama also employ physical movements).

In addition to the schools of Yoga described above, TM® and the secular meditation techniques RR and CSM are derived from classical yogic techniques. It is important to note that the techniques in any given school or type of Yoga represent distinct interventions, in much the same way that psychodynamic, cognitive-behavioral, and interpersonal therapies each involve different approaches to psychotherapy.

The purpose of asanas, pranayams, and pratyahar (emancipation of the mind from the domination of the senses) is to help rid the practitioner of the distractions of body, breath, and sensory activity and to prepare the body and mind for meditation and spiritual development. The use of mantras is said to help cleanse and restructure the subconscious mind, and to help prepare the conscious mind to experience the various states of superconsciousness. The more advanced Yoga practices lie in dharana (concentration), dhyana (yogic meditation) and samadhi (absorption). Concentration involves attention to a single object or place, external or internal (e.g., the space between the eyebrows, the tip of the nose, the breath, a mantra [chanted loudly, softly, or silently] or attention to all of these elements simultaneously). When the mind flows toward the object of concentration uninterruptedly and effortlessly, it is meditation. When it happens for a prolonged period of time it leads to samadhi, the comprehension of the true nature of reality that ultimately leads to enlightenment and emancipates the practitioner from the bonds of time and space.