Meditation increases grey matter in right hemisphere of the brain
The following is a collection of pointers about meditation: what benefits derived from it, the areas of the brain affected, types of meditation and tools used in the research.
A summary of the findings:
- Benefits and other effects:
- moderates heart and breathing rates and integrates cognition, emotions and physiology
- slow age-related thinning of the prefrontal cortex
- restores energy
- less sleep
- better attention/concentration
- loss of sense of space
- loss of sense of self
- boosts immune system (?)
- Areas affected:right-side insula, small section of the prefrontal cortex, expansion of blood vessels
- Meditation practices mentioned: Mindfulness, Tibetan, Vipassana(Insight meditation), Yoga
- Tools: Magnetic resonance imaging (MRI)
- Criticisms
At the end of this post, I have included links to a BBC article on meditation, and about meditation in prisons. Other benefits of meditation not discussed here are the use of it to rid of our mental viruses
Courant: Meditating May Keep Brain Sharp
In the study, published in the current issue of NeuroReport, the researchers found four areas of meditators' brains to be thicker than those of non-meditators, and two were of particular interest: the right-side insula, which is part of the brain's cerebral cortex, and a small section of the prefrontal cortex.
The insula is "a wonderful area of the brain," said Sara Lazar, a research neuroscientist at Mass General, lead author of the study and an experienced meditator. She described it as a kind of central switchboard that "connects the reptilian brain with higher-order cortical areas." It moderates heart and breathing rates and integrates cognition, emotions and physiology.
The prefrontal cortex governs decision-making and working memory. The thickness of this brain area decreases with age, which, according to Lazar "contributes to why we forget where we left our keys. " Lazar and her colleagues observed that this brain shrinkage was less pronounced in older meditators than in older non-meditators, suggesting that meditation may slow age-related thinning of the prefrontal cortex.
The meditators in the study practice a form of Buddhist meditation called insight meditation, which is based on paying close attention to sensations and thoughts as they come and go each passing moment. Those included in the study meditated at least once a day for about 40 minutes, and each of the meditation-group subjects had participated in at least one weeklong retreat.
The brain-thickening phenomenon could be related to any or all of the following: the growth and branching of nerves in the area, an increase in the number of glial, or support cells, and an expansion of blood vessels in the region, according to Jeremy Gray, an assistant professor of psychology at Yale and a co-author.
New Scientist:Meditation builds up the brain
Meditating does more than just feel good and calm you down, it makes you perform better – and alters the structure of your brain, researchers have found.
People who meditate say the practice restores their energy, and some claim they need less sleep as a result. Many studies have reported that the brain works differently during meditation – brainwave patterns change and neuronal firing patterns synchronise. But whether meditation actually brings any of the restorative benefits of sleep has remained largely unexplored.
What effect meditating has on the structure of the brain has also been a matter of some debate. Now Sara Lazar at the Massachusetts General Hospital in Boston, US, and colleagues have used MRI to compare 15 meditators, with experience ranging from 1 to 30 years, and 15 non-meditators.
They found that meditating actually increases the thickness of the cortex in areas involved in attention and sensory processing, such as the prefrontal cortex and the right anterior insula.
“You are exercising it while you meditate, and it gets bigger,” she says. The finding is in line with studies showing that accomplished musicians, athletes and linguists all have thickening in relevant areas of the cortex. It is further evidence, says Lazar, that yogis “aren’t just sitting there doing nothing".
The growth of the cortex is not due to the growth of new neurons, she points out, but results from wider blood vessels, more supporting structures such as glia and astrocytes, and increased branching and connections.
Medical News Today: Meditation associated with increased grey matter in the brain
"What is most fascinating to me is the suggestion that meditation practice can change anyone's grey matter," Gray said. "The study participants were people with jobs and families. They just meditated on average 40 minutes each day, you don't have to be a monk."
Magnetic resonance imaging showed that regular practice of meditation is associated with increased thickness in a subset of cortical regions related to sensory, auditory, visual and internal perception, such as heart rate or breathing. The researchers also found that regular meditation practice may slow age-related thinning of the frontal cortex. "Most of the regions identified in this study were found in the right hemisphere," the researchers said. "The right hemisphere is essential for sustaining attention, which is a central practice of Insight meditation."
BBC: Meditation mapped in monks
During meditation, people often feel a sense of no space Scientists investigating the effect of the meditative state on Buddhist monk's brains have found that portions of the organ previously active become quiet, whilst pacified areas become stimulated. Using a brain imaging technique, Newberg and his team studied a group of Tibetan Buddhist monks as they meditated for approximately one hour. The scans provided remarkable clues about what goes on in the brain during meditation.
"There was an increase in activity in the front part of the brain, the area that is activated when anyone focuses attention on a particular task," Dr Newberg explained.
In addition, a notable decrease in activity in the back part of the brain, or parietal lobe, recognised as the area responsible for orientation, reinforced the general suggestion that meditation leads to a lack of spatial awareness. Scientific study of both the physical world and the inner world of human experiences are, according to Dr Newberg, equally beneficial.
"When someone has a mystical experience, they perceive that sense of reality to be far greater and far clearer than our usual everyday sense of reality," he said.
He added: "Since the sense of spiritual reality is more powerful and clear, perhaps that sense of reality is more accurate than our scientific everyday sense of reality."
Dr Newberg explained: "During meditation, people have a loss of the sense of self and frequently experience a sense of no space and time and that was exactly what we saw."
BBC: Meditation 'good for brain'
Scientists say they have found evidence that meditation has a biological effect on the body. A small-scale study suggests it could boost parts of the brain and the immune system.
Caution: A British expert says the results - published in the journal Psychosomatic Medicine - are interesting but need further scrutiny. "There is increasing evidence that meditation is a useful and, for some people, a powerful therapy," said Dr Adrian White of the department of Complementary Medicine at the University of Exeter. "But we still need more information to determine who it helps and precisely what its benefits are."
BBC: Meditation 'brain training' clues
The researchers studied Tibetan Buddhist monks Meditating monks are giving clues about how the brain's basic responses can be overridden, researchers say. Australian scientists gave Buddhist monks vision tests, where each eye was concurrently shown a different image. Most people's attention would automatically fluctuate - but the monks were able to focus on just one image. Writing in Current Biology, the scientists say their ability to override this basic mental response indicates how the brain can be trained. Meditation is a way of tapping into a process of manipulating brain activity
BBC:Prisoners benefit from meditation
The technique, known as Vipassana Meditation, has been offered in several prisons in India, the US and New Zealand.
Other links: Sara Lazar's web
Sara Lazar publications
Science Heros on Sara Lazar
Criticisms:
Mindhacks:
one of the criticisms was that the study simply compared meditators to non-meditators without following them up to actually see if the cortex did change over time. It could be argued that people with more grey matter are simply more likely to meditate, rather than the act of meditation having any direct effect on grey matter.
Interview with Sara Lazar:
reply to criticsm
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