Meditation: Encyclopedia II - Meditation - Health applications and clinical studies of meditation

Meditation - Health applications and clinical studies of meditation

In the recent years there has been a growing interest within the medical community to study the physiological effects of meditation (Venkatesh et al., 1997; Peng et al., 1999; Lazar et al., 2000; Carlson et.al, 2001). Many concepts of meditation have been applied to clinical settings in order to measure its effect on somatic motor function as well as cardiovascular and respiratory function. Also the hermeneutic and phenomenological aspects of meditation are areas of growing interest. Meditation has entered the mainstream of health care as a method of stress and pain reduction. For example, in an early study in 1972, transcendental meditation was shown to affect the human metabolism by lowering the biochemical byproducts of stress, such as lactate, decreasing heart rate and blood pressure and inducing favorable brain waves. (Scientific American 226: 84-90 (1972))

As a method of stress reduction, meditation is often used in hospitals in cases of chronic or terminal illness to reduce complications associated with increased stress including a depressed immune system. There is a growing consensus in the medical community that mental factors such as stress significantly contribute to a lack of physical health, and there is a growing movement in mainstream science to fund research in this area (e.g. the establishment by the NIH in the U.S. of 5 research centers to research the mind-body aspects of disease.) Dr. James Austin, a neurophysiologist at the University of Colorado, reported that Zen meditation rewires the circuitry of the brain in his landmark book Zen and the Brain (Austin, 1999). This has been confirmed using sophisticated imaging techniques which examine the electrical activity of the brain.

Dr. Herbert Benson of the Mind-Body Medical Institute, which is affiliated with Harvard and several Boston hospitals, reports that meditation induces a host of biochemical and physical changes in the body collectively referred to as the "relaxation response" (Lazar et.al, 2003). The relaxation response includes changes in metabolism, heart rate, respiration, blood pressure and brain chemistry. Benson and his team have also done clinical studies at Buddhist monasteries in the Himalayan Mountains.

Among other well-known studies within this particular field of interest we find the research of Jon Kabat-Zinn and his colleagues at the University of Massachusetts who have done extensive research on the effects of mindfulness meditation on stress (Kabat-Zinn et.al, 1985; Davidson et.al, 2003).

Meditation - Meditation and the brain

Mindfulness meditation and related techniques are intended to train attention for the sake of provoking insight. Think of it as the opposite of attention deficit disorder. A wider, more flexible attention span makes it easier to be aware of a situation, easier to be objective in emotionally or morally difficult situations, and easier to achieve a state of responsive, creative awareness or "flow".

One theory, presented by Daniel Goleman & Tara Bennett-Goleman (2001), suggests that meditation works because of the relationship between the amygdala and the prefrontal cortex. In very simple terms, the amygdala is the part of the brain that decides if we should get angry or anxious (among other things), and the pre-frontal cortex is the part that makes us stop and think about things (it is also known as the inhibitory centre).

So, the prefrontal cortex is very good at analyzing and planning, but it takes a long time to make decisions. The amygdala, on the other hand, is simpler (and older in evolutionary terms). It makes rapid judgements about a situation and has a powerful effect on our emotions and behaviour, linked to survival needs. For example, if a human sees a lion leaping out at them, the amygdala will trigger a fight or flight response long before the prefrontal cortex knows what's happening.

But in making snap judgments, our amygdalas are prone to error, seeing danger where there is none. This is particularly true in contemporary society where social conflicts are far more common than encounters with predators, and a basically harmless but emotionally charged situation can trigger uncontrollable fear or anger — leading to conflict, anxiety, and stress.

Because there is roughly a quarter of a second gap between the time an event occurs, and the time it takes the amygdala to react, a skilled meditator may be able to intervene before a fight or flight response takes over, and perhaps even redirect it into more constructive or positive feelings.

The different roles of the amygdala and prefrontal cortex can be easily observed under the influence of various drugs. Alcohol depresses the brain generally, but the sophisticated prefrontal cortex is more affected than less complex areas, resulting in lowered inhibitions, decreased attention span, and increased influence of emotions over behaviour. Likewise, the controversial drug ritalin has the opposite effect, because it stimulates activity in the prefrontal cortex.

Some studies of meditation have linked the practice to increased activity in the left prefrontal cortex, which is associated with concentration, planning, meta-cognition (thinking about thinking), and with positive affect (good feelings). There are similar studies linking depression and anxiety with decreased activity in the same region, and/or with dominant activity in the right prefrontal cortex. Meditation increases activity in the left prefrontal cortex, and the changes are stable over time — even if you stop meditating for a while, the effect lingers.

Meditation - Meditation and EEG's

Electroencephalographs (EEG) recordings of skilled meditators showed gamma wave activity that gradually expanded across the brain during meditation. Gamma waves indicate synchrony between sections of the brain. These meditators had 10 to 40 years of training in Buddhist-based mental training. EEGs done on meditators who had received recent training turned up considerably less synchrony.

The experienced meditators also showed increased gamma activity while at rest and not meditating. The results of the study do not make clear whether meditation training creates this activity or if individuals with high gamma activity are attracted to meditation. (Antoine Lutz & Richard J. Davidson, 2004).

Meditation also affects brain wave production as measured by an EEG machine. While the brain at a waking state is primarily in the Beta range of frequencies (14 - 21 cycles per second), while under meditation the brain tends to slow down the Alpha range (7 - 14 cycles per second). One of the first Americans to study the effects of meditation on brainwave production was José Silva who founded the Silva Method. Silva theorized that meditation, in addition to stress relief, could also be used for enhancing creativity and developing intuition.

Meditation - Adverse effects

Predominantly, studies of meditation report positive effects. However, some studies report that meditation may have adverse effects in certain circumstances (Lukoff, Lu & Turner, 1998; Perez-De-Albeniz & Holmes, 2000). If practiced improperly or too intensely, meditation can lead to considerable psychological and physiological problems, such as the symptoms of Kundalini syndrome, Shamanic illness, Tumo or Qi-gong-related problems . Serious, and credible teachers of meditation usually warn their students about the possible pitfalls of a contemplative path. Another issue concerns the adaptation of eastern meditative concepts to a western culture, an adaptation that is often unfamiliar with the cultural matrix that the meditative concept originated from. Eastern concepts of meditation are often imported to a western setting within the popular context of new religious movements, or within the context of popular approaches to body and health. It is common for this popular context to be unfamiliar with the broad range of adverse affects that might occur during meditation, and to have limited tools for dealing with them when they do arise.

Stories of unguided practitioners or inexpertly guided students developing chronic mental and physical health problems as a result of their attempts at meditation training are not uncommon. English speaking practitioners and teachers of Chinese Qigong and related disciplines note that the practice of this contemplative exercise is sometimes accompanied by physical and psychological distress. The identification of this syndrome has led to the inclusion of a culture-sensitive category in the DSM-IV called Qi-Gong Psychotic Reaction (American Psychiatric Association, 1994: Appendix 1).

Since the practice of meditation may include a powerful confrontation with existential questions, it is not considered wise to engage in intense meditation techniques without an extended period of psychological preparation, preferably in contact with a credible teacher or clinician. In the case of Asian contemplative traditions there often exist major challenges connected to the way the particular tradition is to be applied to a Western culture, or a Western mindset. A growing body of clinical literature is now starting to address the phenomenon of meditation-related problems (Lukoff, Lu & Turner, 1998; Perez-De-Albeniz & Holmes, 2000). Several side-effects have been reported, including uncomfortable kinaesthetic sensations, mild dissociation and psychosis-like symptoms (Craven, 1989). From a clinical study of twenty-seven long term meditators, Shapiro (1992) reported such adverse effects as depression, relaxation-induced anxiety and panic, paradoxical increases in tension, impaired reality testing, confusion, disorientation and feeling 'spaced out'. The possibility that meditation might trigger strong emotional reactions is also reported by Kutz, Borysenko & Benson (1985). Within the context of therapy, meditation is usually contraindicated when the therapeutic goal is to strengthen ego boundaries, release powerful emotions, or work through complex relational dynamics (Bogart, 1991).

The tendency of meditation to disturb object-relations and release unconscious material implies that the beginning meditator should approach the practice with moderation. It usually takes years of dedication to become stable in a contemplative practice, a perspective that is often overlooked by many new religious movements and New Age therapies.

Meditative traditions which include the use of drugs are generally considered to be harmful to the practitioner. Additionally, as with any practice, meditation may also be used to avoid facing ongoing problems or emerging crises in the meditator's life. In such situations, it may be helpful to apply mindful attitudes acquired in meditation while actively engaging with current problems (see Hayes et al, 1999, chap. 3; Metzner, 2005).

Meditation - Meditation and drugs

Some modern methods of meditation do not include the use of drugs due to the known health problems associated with drug use. However, the use of stimulants has been proposed by some as a means to provide insight, and in some shamanistic traditions they are used as agents of ritual. Some Native American traditions for instance emphasized the smoking of a pipe containing tobacco or other plants. Some Hindu traditions use bhang, East Asian traditions use tea and Middle Eastern (and many Western) religions use coffee as an aid to meditation. During the 1960s, eastern meditation traditions and LSD became popular among many people, and many people suggested that LSD use and meditation were both means to the same spiritual/existential end. However, many people who had already been familiar with eastern traditions rejected this idea, including many who had tried LSD themselves. In The Master Game, de Ropp said that the door to full consciousness could be glimpsed through with the aid of substances, yet to pass beyond the door required yoga and meditation.

Adapted from the Wikipedia article "Health applications and clinical studies of meditation", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki