Does Meditation Change The Brain? — Part 1
The Indian Seers and Sages had known the efficacy of meditation in influencing the behavior, temperamental attitude and bodily health of a person ever since the Vedic times. Various techniques of meditation taking the breath, thought or a mantra as a prop were extensively developed and people were taught to seamlessly sew these practices into their daily routine like having a bath or eating food. Bhagavad-Gita devoted a chapter on the method of meditation spelling out in detail the sitting posture, where and on what one should be seated and so on. Buddhism too absorbed these routines and made “dhyana” in various forms as an important part of the daily ritual.
Sankara gives paramount importance to meditation in Vivekachudamani. He says, “As gold purified in the furnace, rids itself of dross and reaches the quality of its own self, so the mind ridding itself of the dross of substance and darkness, through meditation, enters into reality.” At several places of the text he describes the way a seeker should meditate. He declares in the 358th verse that a man attached to the Truth becomes Truth through his one-pointed devotion just like an insect intensely focused on a dragon fly flies away from the cocoon. This simile tells us how intense thought goes to modify the brain. Though the terminology of our ancients was not the same as that of Neuroscience, the effect that meditation can have on the brain is well known to them. The changes that take place in the brain in its neural pathways and synapses due to changes in behavior, environment and neural processes is called as “Neural Plasticity.”
Brain Scientists have recognized the plasticity of the brain increasingly during the past two to three decades. It is now known that every action, every thought and even the morning cup of coffee you drink changes the connections between different brain cells, redefining the sum total of what you are every moment. Our brains are not like rigid printed circuit boards. The cell connectivities are highly labile and constantly re-forming. There is no storage device comparable to a printed tape or a hard drive in our brain. Our memories are formed anew every time we recall an event. It is never an exact Xerox copy we recollect each time we retrieve the information from our memory.
A few decades back it was thought that the brain once gets fixed in early childhood would not change later. Today Neuroscience tells us that mental training through meditation can lead to “long-lasting changes” in our brain. Psychiatrist Dr. Schwartz observed that the conclusions coming out of the modern studies on brain “would be right at home in the cannons of some of the Eastern Philosophies.”
The Dalai Lama actively promoted the scientific study of meditation for over a decade and half. Buddhism with its dictum that “empirical evidence should triumph over scriptural authority in the investigation of reality, no matter how deeply venerated a scripture may be,” was helpful to this thrust. Unlike in the past, many researchers, aided by modern advances in electronic instrumentation and current developments in Neuroscience, are now coming forward to take up studies in teasing out the changes that occur in the brain as a result of meditational practices.
Mahesh Yogi was perhaps the first to initiate systematically a scientific investigation into meditation over 40 years ago. His group reported many downstream benefits of Transcendental Meditation (TM). Some of the benefits from TM are:
– More widely distributed somatosensory stimuli across the cortex;
– Higher mean EEG coherence over all brain areas;
– State of deep rest with reduced respiration rate and reduced skin conductance;
– Reduced blood pressure and cholesterol levels;
– Younger biological age.
Dr. Herb Besnon’s team at Harvard Medical School studied Sikhs in Meditation. Brain areas associated with attention, space-time concepts and executive control were active during meditation. There was increased blood flow in the limbic system and brain stem that control autonomous nervous system. Dr. Benson noted that relaxation exercises (akin to meditation) released “increasing amounts of nitric oxide which counters the negative effects of the stress hormone norepinephrine.” As a result, the body feels remarkably calm. He also documented an unexplained phenomenon – the extra-ordinary capacity of some Buddhist monks who could dry icy wet sheets spread on their naked bodies in near freezing temperatures while they were meditating in snowy Himalayan peaks!
Dr. Andrew Newberg observed that, during peak moments of mediation, neurons in the posterior superior parietal lobe (responsible to give us orientation in space) exhibited unusual activity. Work by Dr. Beaugard treating patients of spider phobia demonstrated “systematic changes in prefrontal cortex (behind the eyebrows) after Cognitive Behavioral Therapy (CBT).” In CBT, much like in meditation, ‘one places greater emphasis on viewing one’s own thoughts in a detached manner rather than trying to dispute or evaluate their content.’
Dr. J.M. Schwartz designed a protocol for the treatment of Obsessive Compulsive Disorder based on the Buddhist meditation of “Mindfulness Attention.” He showed that a change takes place in the metabolism of caudate nucleus (one of the innermost part of the brain) along with alterations in the neural connections in some other parts of the brain as a result of practicing this technique. Dr. R. Davidson of Wisconsin-Madison found in his studies with the Buddhist Meditation practitioners that mental training through meditation could induce short-term or long-term neural changes. Many research workers established that large areas of the brain, particularly in the left prefrontal cortex (behind the left forehead) were active during meditation. This part of brain is responsible for positive emotions.
Alpha waves in 8 – 13 Hz range are produced in a meditative brain. A person’s peak performance (say in sports) and creative inspiration are associated with bursts of alpha waves. More alpha waves mean less anxiety, better immune system and hence better health.
Dr. J. Austin found a reduction in the breaths from about 12-18 per minute to 4-6 a minute during meditation. He also said that exhalation quiets the activity of the brain cells whereas inhalation has the opposite effect. An overall reduction in oxygen consumption is also observed during meditation.
Dr. M. Beauregard’s work with Carmelite nuns showed that a network of brain regions including those associated with emotion processing and spatial representation of self were involved in deep meditative states. Dr. S. Lazar found that the Buddhist “Insight Meditation” increased the thickness of the cortex in areas connected with attention and sensory processing (prefrontal cortex and right anterior insula). The changes she noticed in the brain structure were comparable to what happened in the case of well-practiced and accomplished musicians or athletes. With meditation the brain tissue thickens like the muscles do with exercise. Here is a Video link to a short presentation by her on “How meditation can reshape our brains”:
http://www.youtube.com/watch?v=m8rRzTtP7Tc&NR=1&feature=endscreen
Work by several Neuroscientists showed that meditation enhances the brain’s ability to modify maladaptive emotional responses like depression. A neurological term, “Self-directed Neuroplasticity” describes the principle that focused training can systematically alter brain function in a useful manner. Some of the scientists hope even to assist spiritual transformation of individuals from neurobiological knowledge.
Prof. R. deCharms of Omneuron is working on a way to use fMRI scans to show brain activity — in real time. One can actually see how one feels in his/her brain while lying down in the scanner. Patients suffering from pain reported substantial reduction in pain following the live feedback they thus obtained. Here is a Video link to a short lecture of Prof. deCharms at TED.
http://www.ted.com/talks/christopher_decharms_scans_the_brain_in_real_time.html
Dr. Daniel Bor, the British Neuroscientist is unequivocal about the effect of Meditation on brain. He observes that “In striking contrast to the effects of anxiety and stress, the simple act of entering a meditative state increases activity in the prefrontal parietal network, especially in the lateral prefrontal cortex. So, intriguingly, this is indirect objective evidence that meditation really does raise awareness.” He says that as a result of the meditational practices, the fear and anxiety module (amygdala) in the brain forfeits its control in favor of the prefrontal cortex (behind the forehead). Consequently one overcomes the debilitating disorders like depression and anxiety. Further, “There is evidence that long-term meditation increases the thickness of the prefrontal cortex, helping to protect against the natural thinning of this part of the brain in old age. A mere two months of meditation is sufficient to shrink the size of the fear-creating amygdale in previously stressed individuals”.
Long-term meditators report ‘becoming profoundly calm, largely free from fear, and better able to handle pains and bothersome emotions when they do arise. They describe a greater degree of awareness and mental control, as if they somehow have more space and flexibility by which to perceive and handle all the details of the world and their own inner life.’ Long-term meditation also improves ‘a range of attentional tasks as well as working memory skills and spatial processing. Strikingly, regular meditation also seems to reduce a person’s need for sleep, possibly because it is a neutrally nourishing activity.’ Research with volunteers showed that ‘just four meditation sessions were sufficient to reduce feelings of tiredness and increase working memory performance.’
Dr. Bor concludes that “for normal healthy participants, meditation reduces stress, improves alertness, and enhances performance on an impressive array of demanding tasks. It’s unsurprising, therefore, that meditation is increasingly being used as an effective weapon against depression, anxiety disorder, severe pain management, schizophrenia, and a host of other conditions.” However, meditation is not a panacea. The Dalai Lama puts in proper perspective the advantage of meditation: “The purpose of meditation is not to cure physical ailments, but to free people from emotional suffering.”
[Note: Parts of this article are adopted from “Effect of Meditation on the Brain” in “Religion Demystified – Understanding Life’s Mysteries in terms of Latest Scientific Findings”, ISBN 978-81-7525-971-3, 2008.]
(To Continue — Part 2)
