Research on meditation
Since the 1950s hundreds of studies on meditation have been conducted, though many of the early studies were flawed and thus yielded unreliable results. More recent reviews have pointed out many of these flaws with the hope of guiding current research into a more fruitful path.
Research on the processes and effects of meditation is a growing subfield of neurological research. Modern scientific techniques and instruments, such as fMRI and EEG, have been used to see what happens in the bodies of people when they meditate, and how their bodies and brains change after meditating regularly.
- 1 Weaknesses in historic meditation research
- 2 Research by type of meditation
- 3 Research on unspecified or multiple types of meditation
- 4 See also
- 5 References
- 6 External links
Weaknesses in historic meditation research
In June, 2007 the United States National Center for Complementary and Alternative Medicine (NCCAM) published an independent, peer-reviewed, meta-analysis of the state of meditation research, conducted by researchers at the University of Alberta Evidence-based Practice Center. The report reviewed 813 studies involving five broad categories of meditation: mantra meditation, mindfulness meditation, yoga, T'ai chi, and Qigong, and included all studies on adults through September 2005, with a particular focus on research pertaining to hypertension, cardiovascular disease, and substance abuse.
The report concluded, "Scientific research on meditation practices does not appear to have a common theoretical perspective and is characterized by poor methodological quality. Firm conclusions on the effects of meditation practices in healthcare cannot be drawn based on the available evidence. Future research on meditation practices must be more rigorous in the design and execution of studies and in the analysis and reporting of results." (p. 6) It noted that there is no theoretical explanation of health effects from meditation common to all meditation techniques.
A version of this report subsequently published in the Journal of Alternative and Complementary Medicine stated that "Most clinical trials on meditation practices are generally characterized by poor methodological quality with significant threats to validity in every major quality domain assessed". This was the conclusion despite a statistically significant increase in quality of all reviewed meditation research, in general, over time between 1956 and 2005. Of the 400 clinical studies, 10% were found to be good quality. A call was made for rigorous study of meditation. These authors also noted that this finding is not unique to the area of meditation research and that the quality of reporting is a frequent problem in other areas of complementary and alternative medicine (CAM) research and related therapy research domains.
Of more than 3,000 scientific studies that were found in a comprehensive search of 17 relevant databases, only about 4% had randomised controlled trials (RCTs), which are designed to exclude the placebo effect.
A 2013 statement from the American Heart Association evaluated the evidence for the effectiveness of TM as a treatment for hypertension as "unknown/unclear/uncertain or not well-established", and stated: "Because of many negative studies or mixed results and a paucity of available trials... other meditation techniques are not recommended in clinical practice to lower BP at this time."
Research by type of meditation
A 2013 metastudy of mindfulness meditation found moderately improved anxiety and depression. Another study showed higher mindfulness and reduced stress correlated with the number of days meditated per week.
A 2003 meta-analysis found that Mindfulness-Based Stress Reduction (MBSR) may be broadly useful for individuals attempting to cope with clinical and nonclinical problems. Diagnoses for which MBSR was found to be helpful included chronic pain, fibromyalgia, cancer patients and coronary artery disease. Improvements were noted for both physical and mental health measures.
Sahaja yoga and mental silence
Sahaja yoga meditation has been shown to correlate with particular brain and brain wave activity. Some studies have led to suggestions that Sahaja meditation involves 'switching off' irrelevant brain networks for the maintenance of focused internalized attention and inhibition of inappropriate information.
A study comparing practitioners of Sahaja Yoga meditation with a group of non meditators doing a simple relaxation exercise, measured a drop in skin temperature in the meditators compared to a rise in skin temperature in the non meditators as they relaxed. The researchers noted that all other meditation studies that have observed skin temperature have recorded increases and none have recorded a decrease in skin temperature. This suggests that Sahaja Yoga meditation, being a mental silence approach, may differ both experientially and physiologically from simple relaxation. Sahaja meditators scored above peer group for emotional wellbeing measures on SF-36 ratings.
Kundalini yoga meditation research has found that there "appears to produce structural as well as intensity changes in phenomenological experiences of consciousness",[this quote needs a citation] and that multiple regions of the brain are active.
Fifteen Carmelite nuns came from the monastery to the laboratory to enter a fMRI machine whilst meditating, allowing scientists there to scan their brains using fMRI while they were in a state known as Unio Mystica (and also Theoria). The documentary film Mystical Brain by Isabelle Raynauld examined this study.
Integrative body-mind training
A study involving the participation of a group of college students, who were asked to use a meditation technique called integrative body-mind training (IBMT involves body relaxation, mental imagery, and mindfulness training), concluded that "meditating may improve the integrity and efficiency of certain connections in the brain" through an increase in their number and robustness. Brain scans showed strong white matter changes in the anterior cingulate cortex.
The first Transcendental Meditation (TM) research studies were conducted at UCLA and Harvard University and published in Science and the American Journal of Physiology in 1970 and 1971. However, much research has been of poor quality, including a high risk for bias due to the connection of researchers to the TM organization and the selection of subjects with a favorable opinion of TM. Independent systematic reviews have not found health benefits for TM exceeding those of relaxation and health education. A 2013 statement from the American Heart Association described the evidence supporting TM as a treatment for hypertension as Level IIB, meaning that TM "may be considered in clinical practice" but that its effectiveness is "unknown/unclear/uncertain or not well-established".[this quote needs a citation]
Research on unspecified or multiple types of meditation
The medial prefrontal and posterior cingulate cortices have been found to be relatively deactivated during meditation (experienced meditators using concentration, lovingkindness and choiceless awareness meditation). In addition experienced meditators were found to have stronger coupling between the posterior cingulate, dorsal anterior cingulate, and dorsolateral prefrontal cortices both when meditating and when not meditating.
Another study (of Tibetan Buddhist, QiGong, Sahaja Yoga, Ananda Marga Yoga and Zen meditators) found reduced functional interdependence between brain regions in meditation.
Studies have shown that meditation has both short-term and long-term effects on various perceptual faculties. In 1984 a study showed that meditators have a significantly lower detection threshold for light stimuli of short duration. In 2000 a study of the perception of visual illusions by zen masters, novice meditators, and non-meditators showed statistically significant effects found for the Poggendorff Illusion but not for the Müller-Lyer Illusion. The zen masters experienced a statistically significant reduction in initial illusion (measured as error in millimeters) and a lower decrement in illusion for subsequent trials. Tloczynski has described the theory of mechanism behind the changes in perception that accompany mindfulness meditation thus: "A person who meditates consequently perceives objects more as directly experienced stimuli and less as concepts… With the removal or minimization of cognitive stimuli and generally increasing awareness, meditation can therefore influence both the quality (accuracy) and quantity (detection) of perception." Brown also points to this as a possible explanation of the phenomenon: "[the higher rate of detection of single light flashes] involves quieting some of the higher mental processes which normally obstruct the perception of subtle events."[this quote needs a citation] In other words, the practice may temporarily or permanently alter some of the top-down processing involved in filtering subtle events usually deemed noise by the perceptual filters.
Kaul et al. found that sleep duration in long-term experienced meditators was lower than in non-meditators and general population norms, with no apparent decrements in vigilance.
Herbert Benson, founder of the Mind-Body Medical Institute, which is affiliated with Harvard University 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". 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. Benson wrote The Relaxation Response to document the benefits of meditation, which in 1975 were not yet widely known.
According to a March 2006 article in Psychological Bulletin, EEG activity begins to slow as a result of the practice of meditation. The human nervous system is composed of a parasympathetic system, which works to regulate heart rate, breathing and other involuntary motor functions, and a sympathetic system, which arouses the body, preparing it for vigorous activity. The National Institutes of Health (NIH) has written, "It is thought that some types of meditation might work by reducing activity in the sympathetic nervous system and increasing activity in the parasympathetic nervous system,"[this quote needs a citation] or equivalently, that meditation produces a reduction in arousal and increase in relaxation.
A study of GPs attending a meditation workshop found subsequent falls in their Kessler Psychological Distress Scale - 10 (K10) readings.
Western therapeutic use
Meditation has entered the mainstream of health care as a method of stress and pain reduction. As a method of stress reduction, meditation has been used in hospitals in cases of chronic or terminal illness to reduce complications associated with increased stress that include depressed immune systems. There is growing agreement 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. There are now several mainstream health care programs which aid those, both sick and healthy, in promoting their inner well-being, especially mindfulness-based programs such as Mindfulness-Based Stress Reduction (MBSR).
Mindfulness meditation, mindfulness of the breath, and related techniques, are intended to train attention for the sake of provoking insight. 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".
Slowing Ageing Process
Some researches were conducted to understand the malleable determinants of cellular aging, which is critical to understanding human longevity. The researchers concluded saying "We have reviewed data linking stress arousal and oxidative stress to telomere shortness. Meditative practices appear to improve the endocrine balance toward positive arousal (high DHEA, lower cortisol) and decrease oxidative stress. Thus, meditation practices may promote mitotic cell longevity both through decreasing stress hormones and oxidative stress and increasing hormones that may protect the telomere."
Potential adverse effects and limits of meditation
The following is an official statement from the US government-run National Center for Complementary and Alternative Medicine:
"Meditation is considered to be safe for healthy people. There have been rare reports that meditation could cause or worsen symptoms in people who have certain psychiatric problems, but this question has not been fully researched. People with physical limitations may not be able to participate in certain meditative practices involving physical movement. Individuals with existing mental or physical health conditions should speak with their health care providers prior to starting a meditative practice and make their meditation instructor aware of their condition."
Adverse effects have been reported, and may, in some cases, be the result of "improper use of meditation".The NIH advises prospective meditators to "ask about the training and experience of the meditation instructor… [they] are considering."
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 instead be helpful to apply mindful attitudes acquired in meditation while actively engaging with current problems. According to the NIH, meditation should not be used as a replacement for conventional health care or as a reason to postpone seeing a doctor.
- Brain activity and meditation
- Buddhism and psychology
- Buddhist meditation
- Mindfulness (psychology)
- Ospina, Maria B.; Bond, Kenneth; Karkhaneh, Mohammad; Tjosvold, Lisa; Vandermeer, Ben; Liang, Yuanyuan; Bialy, Liza; Hooton, Nicola; Buscemi, Nina; Dryden, Donna M.; Klassen, Terry P. (June 2007). "Meditation practices for health: state of the research". Evidence Report/technology Assessment (155): 1–263. PMID 17764203.
- Lutz, Antoine; Dunne, John D.; Davidson, Richard J. (2007). "Meditation and the Neuroscience of Consciousness: An Introduction". In Zelazo, Philip David; Moscovitch, Morris; Thompson, Evan. The Cambridge Handbook of Consciousness. Cambridge Handbooks in Psychology. Cambridge University Press. pp. 499–552. doi:10.1017/CBO9780511816789.020. ISBN 978-0-511-81678-9.
- Ospina MB, Bond K, Karkhaneh M, et al. (December 2008). "Clinical trials of meditation practices in health care: characteristics and quality". J Altern Complement Med 14 (10): 1199–213. doi:10.1089/acm.2008.0307. PMID 19123875.
- There has been a dramatic increase in the past 10 or 15 years or so of studies on the impact of meditation upon one's health. Translator for The Dalai Lama, interviewed in a video here[dead link][unreliable source?]
- http://www.investigatingthemind.org/ "...the power of our non-invasive technologies have made it possible to investigate the nature of cognition and emotion in the brain as never before..." Mind and Life Institute summary of Investigating the Mind 2005 meetings between The Dalai Lama and scientists[unreliable source?]
- "A study of structure of phenomenology of consciousness in meditative and non-meditative states". Indian Journal of Physiology and Pharmacology 41 (2): 149–53. April 1997. PMID 9142560.
- Peng, C.-K; Mietus, Joseph E; Liu, Yanhui; Khalsa, Gurucharan; Douglas, Pamela S; Benson, Herbert; Goldberger, Ary L (July 1999). "Exaggerated heart rate oscillations during two meditation techniques". International Journal of Cardiology 70 (2): 101–7. doi:10.1016/S0167-5273(99)00066-2. PMID 10454297.
- Lazar, Sara W.; Bush, George; Gollub, Randy L.; Fricchione, Gregory L.; Khalsa, Gurucharan; Benson, Herbert (May 2000). "Functional brain mapping of the relaxation response and meditation". Neuroreport 11 (7): 1581–5. doi:10.1097/00001756-200005150-00041. PMID 10841380.
- Carlson, Linda E.; Ursuliak, Zenovia; Goodey, Eileen; Angen, Maureen; Speca, Michael (March 2001). "The effects of a mindfulness meditation-based stress reduction program on mood and symptoms of stress in cancer outpatients: 6-month follow-up". Supportive Care in Cancer 9 (2): 112–23. doi:10.1007/s005200000206. PMID 11305069.
- mindandlife.org[full citation needed][unreliable source?]
- Davidson, Richard J.; Kabat‐Zinn, Jon; Schumacher, Jessica; Rosenkranz, Melissa; Muller, Daniel; Santorelli, Saki F.; Urbanowski, Ferris; Harrington, Anne; Bonus, Katherine; Sheridan, John F. (2003). "Alterations in Brain and Immune Function Produced by Mindfulness Meditation". Psychosomatic Medicine 65 (4): 564–70. doi:10.1097/01.PSY.0000077505.67574.E3. PMID 12883106.
- Wallace, Robert Keith (March 1970). "Physiological effects of transcendental meditation". Science 167 (3926): 1751–4. doi:10.1126/science.167.3926.1751. PMID 5416544.
- Kabat-Zinn, Jon; Lipworth, Leslie; Burney, Robert (June 1985). "The clinical use of mindfulness meditation for the self-regulation of chronic pain". Journal of Behavioral Medicine 8 (2): 163–90. doi:10.1007/BF00845519. PMID 3897551.
- Awasthi, Bhuvanesh (2012). "Issues and perspectives in meditation research: in search for a definition". Frontiers in Psychology 3: 613. doi:10.3389/fpsyg.2012.00613. PMC 3541715. PMID 23335908.
- Brook, Robert D.; Appel, Lawrence J.; Rubenfire, Melvyn; Ogedegbe, Gbenga; Bisognano, John D.; Elliott, William J.; Fuchs, Flavio D.; Hughes, Joel W.; Lackland, Daniel T.; Staffileno, Beth A.; Townsend, Raymond R.; Rajagopalan, Sanjay (June 2013). "Beyond medications and diet: alternative approaches to lowering blood pressure: a scientific statement from the american heart association". Hypertension 61 (6): 1360–83. doi:10.1161/HYP.0b013e318293645f. PMID 23608661.
- Goyal, Madhav; Singh, Sonal; Sibinga, Erica M. S.; Gould, Neda F.; Rowland-Seymour, Anastasia; Sharma, Ritu; Berger, Zackary; Sleicher, Dana; Maron, David D.; Shihab, Hasan M.; Ranasinghe, Padmini D.; Linn, Shauna; Saha, Shonali; Bass, Eric B.; Haythornthwaite, Jennifer A. (March 2014). "Meditation programs for psychological stress and well-being: a systematic review and meta-analysis". JAMA Internal Medicine 174 (3): 357–68. doi:10.1001/jamainternmed.2013.13018. PMID 24395196.
- Schoormans, Dounya; Nyklíček, Ivan (July 2011). "Mindfulness and psychologic well-being: are they related to type of meditation technique practiced?". Journal of Alternative and Complementary Medicine 17 (7): 629–34. doi:10.1089/acm.2010.0332. PMID 21711203.
- Grossman, Paul; Niemann, Ludger; Schmidt, Stefan; Walach, Harald (July 2004). "Mindfulness-based stress reduction and health benefits. A meta-analysis". Journal of Psychosomatic Research 57 (1): 35–43. doi:10.1016/S0022-3999(03)00573-7. PMID 15256293.
- Aftanas, LI; Golocheikine, SA (September 2001). "Human anterior and frontal midline theta and lower alpha reflect emotionally positive state and internalized attention: high-resolution EEG investigation of meditation". Neuroscience Letters 310 (1): 57–60. doi:10.1016/S0304-3940(01)02094-8. PMID 11524157.
- Aftanas, Ljubomir; Golosheykin, Semen (June 2005). "Impact of regular meditation practice on EEG activity at rest and during evoked negative emotions". The International Journal of Neuroscience 115 (6): 893–909. doi:10.1080/00207450590897969. PMID 16019582.
- Aftanas, LI; Golocheikine, SA (September 2002). "Non-linear dynamic complexity of the human EEG during meditation". Neuroscience Letters 330 (2): 143–6. doi:10.1016/S0304-3940(02)00745-0. PMID 12231432.
- Manocha, Ramesh; Black, Deborah; Spiro, David; Ryan, Jake; Stough, Con (March 2010). "Changing Definitions of Meditation – Is there a Physiological Corollary? Skin temperature changes of a mental silence orientated form of meditation compared to rest". Journal of the International Society of Life Sciences 28 (1): 23–31.
- Beauregard, Mario; Paquette, Vincent (September 2006). "Neural correlates of a mystical experience in Carmelite nuns". Neuroscience Letters 405 (3): 186–90. doi:10.1016/j.neulet.2006.06.060. PMID 16872743.
- Mystical Brain[non-primary source needed]
- "Meditation boosts part of brain where ADD, addictions reside". Ars Technica. Retrieved 2010-08-22.
- Tang, Yi-Yuan; Lu, Qilin; Geng, Xiujuan; Stein, Elliot A.; Yang, Yihong; Posner, Michael I. (August 2010). "Short-term meditation induces white matter changes in the anterior cingulate". Proceedings of the National Academy of Sciences of the United States of America 107 (35): 15649–52. Bibcode:2010PNAS..10715649T. doi:10.1073/pnas.1011043107. JSTOR 27862304. PMC 2932577. PMID 20713717. Lay summary – ScienceDaily (18 August 2010).
- Lyn Freeman, Mosby’s Complementary & Alternative Medicine: A Research-Based Approach, Mosby Elsevier, 2009, p. 163
- Krisanaprakornkit, Thawatchai; Sriraj, Wimonrat; Piyavhatkul, Nawanant; Laopaiboon, Malinee (2006). "Meditation therapy for anxiety disorders". The Cochrane Database of Systematic Reviews (1): CD004998. doi:10.1002/14651858.CD004998.pub2. PMID 16437509.
- Ernst E (2011). Bonow RO, et al, ed. Chapter 51: Complementary and Alternative Approaches to Management of Patients with Heart Disease. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine (9th ed.) (Saunders). ISBN 978-1-4377-2708-1.
A systematic review of six RCTs of transcendental meditation failed to generate convincing evidence that meditation is an effective treatment for hypertension(References the same 2004 systematic review by Canter and Ernst on TM and hypertension that is separately referenced in this article)
- Canter, Peter H; Ernst, Edzard (November 2004). "Insufficient evidence to conclude whether or not Transcendental Meditation decreases blood pressure: results of a systematic review of randomized clinical trials". Journal of Hypertension 22 (11): 2049–54. doi:10.1097/00004872-200411000-00002. PMID 15480084.
- Krisanaprakornkit, Thawatchai; Ngamjarus, Chetta; Witoonchart, Chartree; Piyavhatkul, Nawanant (2010). "Meditation therapies for attention-deficit/hyperactivity disorder (ADHD)". The Cochrane Database of Systematic Reviews (6): CD006507. doi:10.1002/14651858.CD006507.pub2. PMID 20556767.
- Canter, Peter H.; Ernst, Edzard (November 2003). "The cumulative effects of Transcendental Meditation on cognitive function — a systematic review of randomised controlled trials". Wiener Klinische Wochenschrift 115 (21-22): 758–66. doi:10.1007/BF03040500. PMID 14743579.
- Brewer, Judson A.; Worhunsky, Patrick D.; Gray, Jeremy R.; Tang, Yi-Yuan; Weber, Jochen; Kober, Hedy (December 2011). "Meditation experience is associated with differences in default mode network activity and connectivity". Proceedings of the National Academy of Sciences of the United States of America 108 (50): 20254–9. Bibcode:2011PNAS..10820254B. doi:10.1073/pnas.1112029108. JSTOR 23060108. PMC 3250176. PMID 22114193.
- Lehmann, Dietrich; Faber, Pascal L.; Tei, Shisei; Pascual-Marqui, Roberto D.; Milz, Patricia; Kochi, Kieko (April 2012). "Reduced functional connectivity between cortical sources in five meditation traditions detected with lagged coherence using EEG tomography". NeuroImage 60 (2): 1574–86. doi:10.1016/j.neuroimage.2012.01.042. PMID 22266174.
- Lutz, Antoine; Greischar, Lawrence L.; Rawlings, Nancy B.; Ricard, Matthieu; Davidson, Richard J.; Singer, Burton H. (November 2004). "Long-term meditators self-induce high-amplitude gamma synchrony during mental practice". Proceedings of the National Academy of Sciences of the United States of America 101 (46): 16369–73. doi:10.1073/pnas.0407401101. JSTOR 3373824. PMC 526201. PMID 15534199.
- Bhattathiry, M.P. "Neurophysiology of Meditation". Retrieved 2006-08-14.[unreliable source?]
- Brown, Daniel; Forte, Michael; Dysart, Michael (June 1984). "Differences in visual sensitivity among mindfulness meditators and non-meditators". Perceptual and Motor Skills 58 (3): 727–33. doi:10.2466/pms.19188.8.131.527. PMID 6382144.
- Tloczynski, Joseph; Santucci, Aimee; Astor-Stetson, Eileen (December 2000). "Perception of visual illusions by novice and longer-term meditators". Perceptual and Motor Skills 91 (3 Pt 1): 1021–6. doi:10.2466/pms.2000.91.3.1021. PMID 11153836.
- Kaul, Prashant; Passafiume, Jason; Sargent, Craig R; O'Hara, Bruce F (2010). "Meditation acutely improves psychomotor vigilance, and may decrease sleep need". Behavioral and Brain Functions 6: 47. doi:10.1186/1744-9081-6-47. PMC 2919439. PMID 20670413.
- Benson, Herbert (December 1997). "The relaxation response: therapeutic effect". Science 278 (5344): 1693–7. Bibcode:1997Sci...278.1693B. doi:10.1126/science.278.5344.1693b. PMID 9411784.
- Cromie, William J. (18 April 2002). "Meditation changes temperatures: Mind controls body in extreme experiments". Harvard University Gazette. Archived from the original on 24 May 2007.
- Benson, Herbert (2001). The Relaxation Response. HarperCollins. pp. 61–3. ISBN 0-380-81595-8.[non-primary source needed]
- Cahn, B. Rael; Polich, John (March 2006). "Meditation states and traits: EEG, ERP, and neuroimaging studies". Psychological Bulletin 132 (2): 180–211. doi:10.1037/0033-2909.132.2.180. PMID 16536641.
- Manoch, Ramesh; Gordon, Amy; Black, Deborah; Malhi, Gin; Seidler, Raymond (June 2009). "Using meditation for less stress and better wellbeing - A seminar for GPs". Australian Family Physician 38 (6): 454–8. PMID 19530378.
- Marr, Arthur J. (April 2001). "Commentary: In the Zone: A Biobehavioral Theory of the Flow Experience". Athletic Insight 3 (1).
- "Meditation: An Introduction". National Center for Complementary and Alternative Medicine. June 2010.
- Perez-De-Albeniz, Alberto; Holmes, Jeremy (2000). "Meditation: Concepts, effects and uses in therapy". International Journal of Psychotherapy 5 (1): 49–58. doi:10.1080/13569080050020263.
- Rocha, Tomas (25 June 2014). "The Dark Knight of the Soul". The Atlantic.
- Turner, Robert P.; Lukoff, David; Barnhouse, Ruth Tiffany; Lu, Francis G. (July 1995). "Religious or spiritual problem. A culturally sensitive diagnostic category in the DSM-IV". The Journal of Nervous and Mental Disease 183 (7): 435–44. doi:10.1097/00005053-199507000-00003. PMID 7623015.
- Hayes, 1999, chap. 3[full citation needed]
- Metzner, 2005[page needed][full citation needed]
- Marchant, Jo (23 April 2011). "How meditation might ward off the effects of ageing". The Observer.