|Year : 2017 | Volume
| Issue : 4 | Page : 198-201
Neurological benefits of mindfulness meditation
Pushpendra Nath Renjen, Dinesh Mohan Chaudhari
Department of Neurology, Institute of Neurosciences, Indraprastha Apollo Hospitals, New Delhi, India
|Date of Web Publication||5-Feb-2018|
Pushpendra Nath Renjen
C-85, Anand Niketan, New Delhi - 110 021
Source of Support: None, Conflict of Interest: None
Meditation can be defined as a form of mental training that aims to improve an individual's core psychological capacities, such as attentional and emotional self-regulation. Research on the biological concomitants of meditation practice is sparse and has mostly focused on changes that occur during meditation compared with a resting control condition in a single experimental session. Over 2000 scientific publications on the term “meditation” have been published till date, mainly in the scientific fields such of psychology and neuroscience. If supported by rigorous research studies, the practice of mindfulness meditation might be promising for the treatment of clinical disorders and might facilitate the cultivation of a healthy mind and increased well-being.
Keywords: Brain, meditation, mindfulness, yoga
|How to cite this article:|
Renjen PN, Chaudhari DM. Neurological benefits of mindfulness meditation. Apollo Med 2017;14:198-201
| Introduction|| |
Meditation can be defined as a form of mental training that aims to improve an individual's core psychological capacities, such as attentional and emotional self-regulation. Meditation encompasses a family of complex practices that include mindfulness meditation, mantra meditation, yoga, tai chi, and chi gong. With the widespread and growing use of meditative practices in hospitals and academic medical centers for outpatients presenting with a range of chronic stress and pain-related disorders and chronic diseases, under the umbrella of what has come to be called mind/body or integrative medicine, the question of possible biological mechanisms by which meditation may affect somatic, cognitive, and affective processes becomes increasingly important. Research on the biological concomitants of meditation practice is sparse and has mostly focused on changes that occur during meditation compared with a resting control condition in a single experimental session.,,
| Neurological Benefits of Mindfulness Meditation|| |
Neuropsychiatric disorders such as depression, alcohol, and drug abuse are on the increase worldwide. Neuropsychiatric disorders account for 31% of total disability and are expected to rise by 2020. Depression is the most common of all mental disorders with the greatest public health burden. According to estimates from the World Health Organization by 2020 depression will be the leading cause for disability worldwide. Suicide is estimated to be the leading cause of death in young people in 2020. There have been increases in the number of diagnoses of mental health problems including schizophrenia, dementia, alcohol and substance abuse, and most child psychiatric disorders, which in part may be confounded by better detection, improved services, and diagnostic changes. Nevertheless, these will be an increasing part of the overall health burden in the future. Meditation is essentially a physiological state of demonstrated reduced metabolic activity, different from sleep, that elicits physical and mental relaxation and is reported to enhance psychological balance and emotional stability.
According to the Yoga Sutras of Patanjali, one of the oldest recorded scriptures on Meditation, “Yoga is the suppression of the modifications of the mind.” Although today a large variety of meditation practices have emerged, some of them not aiming to achieve anything beyond relaxation, the original goal of meditation is the elimination or reduction of thought processes, the cessation or slowing of the internal dialogue of the mind, the “mental clutter.” This elimination of the thinking process has been reported to lead to a deep sense of physical and mental calm while at the same time enhancing pure awareness, untainted by thoughts, and perceptual clarity. Meditative experiences of thoughtless awareness furthermore seem to trigger feelings of positive emotions which can range from detached serenity to ecstatic bliss. A common experience of meditation is a meta-cognitive shift where thoughts and feelings rather than occupying full attention can be observed from a detached witnessing awareness from which they can be dealt with in a more efficient manner. Achieving this mystical peak experience of complete thoughtless awareness is the ultimate goal of many traditional meditation techniques. However, most meditation techniques have more commonly focused on achieving trait effects in the practitioners such as enhanced concentration which is a prerequisite to achieve the peak experience. Many electrophysiological studies have examined the brain activation during a variety of concentrative meditation techniques. A common finding has been that of increased low-frequency activation of theta and alpha bands that has been suggested to reflect enhanced sustained attention to internal events.
Most modern functional imaging studies have typically been conducted in very small subject numbers and without the use of control conditions. Nevertheless, the findings so far seem to support the evidence that meditation leads to increased activation in frontal and subcortical brain regions that are important for sustained attention and emotion regulation. A study of Lou et al. using positron emission tomography, reported an increase in the left prefrontal and limbic brain regions during the abstract sense of joy compared to rest in nine practitioners of Yoga Nidra Meditation. This is in line with the electroencephalography findings of Aftanas and Golocheikine and supports the hypothesis of a role of the left fronto-limbic networks for the experience of happiness in meditators. Functional magnetic resonance imaging was conducted in a small number of five meditators with at least 4 years of Kundalini Yoga experience, consisting of body postures, breathing exercises, and concentration techniques. The study design contrasted meditation that consisted in passive observation of the breath and the silent repetition of a mantra at exhalation and inhalation with a control condition where subjects silently generated a random list of animals and did not observe their breathing. There was increased activation during late versus early meditation in dorsolateral prefrontal and parietal cortex, limbic and paralimbic regions (amygdala, hypothalamus, hippocampus, and anterior cingulate), and the basal ganglia. The authors interpret their findings as an indication of increased activation of brain regions that mediate sustained attention and autonomic control. Given the very small subject numbers, replication in larger samples will be necessary to corroborate the findings. There is converging evidence that frontoparietal and fronto-limbic brain networks seem to be activated in the attention practices that lead to meditation, presumably reflecting processes of internalized sustained attention and emotion regulation. Hereby, the most consistent findings across meditation imaging studies are the functional upregulation of brain regions that are known to mediate attention control. Various brain regions involved in the components of mindfulness meditation have been extensively studied [Figure 1].
|Figure 1: Brain regions involved in the components of mindfulness meditation. Schematic view of some of the brain regions involved in attention control (the anterior cingulate cortex and the striatum), emotion regulation (multiple prefrontal regions, limbic regions, and the striatum) and self-awareness (the insula, medial prefrontal cortex and posterior cingulate cortex and precuneus)|
Click here to view
Meditation has been the subject of scientific research since the 1950s although widespread scientific interest was only reached in the 1990s [Figure 2]. Today, over 2000 scientific publications on the term “meditation” have been published, mainly in the scientific fields such of psychology and neuroscience.
|Figure 2: Search results for the term meditation from PubMed, 1990-2009. (Adopted from Braboszcz et al., 2009)|
Click here to view
Lazar et al., studied twenty participants with extensive training in Insight meditation were recruited from local meditation communities. These participants were not monks, but rather typical Western meditation practitioners who incorporate their practice into a daily routine involving career, family, friends, and outside interests. Two participants were full-time meditation teachers, three were part-time yoga or meditation teachers and the rest meditated an average of once a day for 40 min, while pursuing traditional careers in fields such as healthcare and law. On average, participants had 9.1 ± 7.1 years of meditation experience and practiced 6.2 ± 4.0 h/week. Study results suggest that meditation may be associated with structural changes in areas of the brain that are important for sensory, cognitive, and emotional processing [Figure 3]. The data further suggest that meditation may impact age-related declines in cortical structure.
|Figure 3: Cortical regions thicker in meditators than in controls. (a and b) Statistical map depicting between-group differences in thickness at each point on the cortical surface overlaid on the inflated average brain. Numbered regions: (1) Insula, (2) Brodmann area (BA) 9/10, (3) somatosensory cortex, (4) auditory cortex. (c and d) Scatter plot of mean cortical thickness of each participant in the subregion above threshold within each circled region of (c) insula and (d) BA 9/10, plotted versus age. Meditation participants: Blue circles; control participants: Red squares|
Click here to view
In 2008, Hölzel et al., investigated MRI brain images of 20 mindfulness (Vipassana) meditators (mean practice 8.6 years; 2 h daily) using voxel-based morphometry and compared the regional gray matter concentration (GMC) to that of nonmeditators matched for sex, age, education, and handedness. The present study showed a distinct pattern of GMC in meditators, who spent a significant part of their lifetime training nonjudgmental acceptance toward internal experiences that arise at each moment. Regular meditation practice is associated with structural differences in regions that are typically activated during meditation, such as the inferior temporal gyrus and hippocampus as well as in regions that are relevant for the task of meditation, such as the insula and orbitofrontal cortex.
Later on Hölzel et al., went on to study mindfulness-based stress reduction (MBSR), one of the most widely used mindfulness training programs, that has been reported to produce positive effects on psychological well-being and to ameliorate symptoms of a number of disorders. They conducted a controlled longitudinal study to investigate pre-post changes in brain GMC attributable to participation in an MBSR program. Anatomical MRI images from sixteen healthy, meditation-naïve participants were obtained before and after they underwent the 8-week program. Changes in GMC were investigated using voxel-based morphometry, and compared to a wait-list control group of 17 individuals. Analyses in a priori regions of interest confirmed increases in GMC within the left hippocampus. Whole brain analyses identified increases in the posterior cingulate cortex, the temporoparietal junction, and the cerebellum in the MBSR group compared to the controls. The results suggest that participation in MBSR is associated with changes in GMC in brain regions involved in learning and memory processes, emotion regulation, self-referential processing, and perspective taking [Figure 4].
|Figure 4: Region of interest analysis identifies gray matter concentration increases in the left hippocampus MNI coordinates x = −36 (a), y = −34 (b), z = −8 (c) in the mindfulness-based stress reduction group. Voxels (thresholded at P = 0.01 and masked for the regions of interest) are overlaid over the group-averaged brain. (d) Change in gray matter concentration within the cluster in the left hippocampus from the pre- to the post-time-point in the mindfulness-based stress reduction and the control group; error bars show 95% confidence interval|
Click here to view
| Conclusion|| |
Increasing awareness and curiosity for various scientifically proven health benefits of mindfulness meditation has been the major key factor for research on meditation. As mentioned earlier, over 2000 scientific publications on the term “meditation” have been published till date, mainly in the scientific fields such of psychology and neuroscience. Knowledge of the mechanisms that underlie the effects of meditation is still in its infancy. However, there is emerging evidence that mindfulness meditation might cause neuroplastic changes in the structure and function of brain regions involved in regulation of attention, emotion and self-awareness. Further research needs to use longitudinal, randomized, and actively controlled research designs and larger sample sizes to advance the understanding of the mechanisms of mindfulness meditation in regard to the interactions of complex brain networks and needs to connect neuroscientific findings with behavioral data. If supported by rigorous research studies, the practice of mindfulness meditation might be promising for the treatment of clinical disorders and might facilitate the cultivation of a healthy mind and increased well-being.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Ospina MB, Bond K, Karkhaneh M, Tjosvold L, Vandermeer B, Liang Y, et al.
Meditation practices for health: State of the research. Evid Rep Technol Assess (Full Rep) 2007;155:1-263.
Lou HC, Kjaer TW, Friberg L, Wildschiodtz G, Holm S, Nowak M, et al.
A15O-H2O PET study of meditation and the resting state of normal consciousness. Hum Brain Mapp 1999;7:98-105.
Jevning R, Anand R, Biedebach M, Fernando G. Effects on regional cerebral blood flow of transcendental meditation. Physiol Behav 1996;59:399-402.
Herzog H, Lele VR, Kuwert T, Langen KJ, Rota Kops E, Feinendegen LE, et al.
Changed pattern of regional glucose metabolism during yoga meditative relaxation. Neuropsychobiology 1990;23:182-7.
Mathers CD, Loncar D. Updated projections of global mortality and burden of disease, 2002–2030 data sources, methods and results. Evidence and Information for Policy Working Paper, Geneva, Switzerland World Health Organization. 2006.
Rubia K. The neurobiology of meditation and its clinical effectiveness in psychiatric disorders. Biol Psychol 2009;82:1-1.
Jevning R, Wallace RK, Beidebach M. The physiology of meditation: A review. A wakeful hypometabolic integrated response. Neurosci Biobehav Rev 1992;16:415-24.
Shearer A. The Yoga Sutras of Patanjali. Editor and Translation. Patanjali; 1993.
Cahn BR, Polich J. Meditation states and traits: EEG, ERP, and neuroimaging studies. Psychol Bull 2006;132:180-211.
Aftanas LI, Golocheikine SA. Non-linear dynamic complexity of the human EEG during meditation. Neurosci Lett 2002;330:143-6.
Lazar SW, Bush G, Gollub RL, Fricchione GL, Khalsa G, Benson H, et al.
Functional brain mapping of the relaxation response and meditation. Neuroreport 2000;11:1581-5.
Tang YY, Hölzel BK, Posner MI. The neuroscience of mindfulness meditation. Nat Rev Neurosci 2015;16:213-25.
Braboszcz C, Hahusseau S, Delorme A. Meditation and neuroscience: From basic research to clinical practice. In: Carlstedt RA, editor. Integrative Clinical Psychology, Psychiatry and Behavioral Medicine: Perspectives, Practices and Research. New York: Springer Publishing Company; 2009. p. 1910-29.
Lazar SW, Kerr CE, Wasserman RH, Gray JR, Greve DN, Treadway MT, et al.
Meditation experience is associated with increased cortical thickness. Neuroreport 2005;16:1893-7.
Hölzel BK, Ott U, Gard T, Hempel H, Weygandt M, Morgen K, et al.
Investigation of mindfulness meditation practitioners with voxel-based morphometry. Soc Cogn Affect Neurosci 2008;3:55-61.
Hölzel BK, Carmody J, Vangel M, Congleton C, Yerramsetti SM, Gard T, et al.
Mindfulness practice leads to increases in regional brain gray matter density. Psychiatry Res 2011;191:36-43.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]