Your Brain on Meditation
People have been meditating for so long that no one can really say when or how it got started, but the reasons they do it haven’t changed much. Over the centuries, meditators have consistently found that their practice keeps them focused and emotionally stable, helps them to adapt to new situations, cope with stress in a positive manner, and be more creative. And yet, there is something more to it.
It’s difficult to define meditation in a way that accounts for the wide variety within established meditation traditions. Undoubtedly, specific techniques have evolved within each tradition to address specific human needs and to develop specific potentials, but much of what people call meditation may be better described as systematic relaxation, visualization, working with the breath, simple concentration, or just “spacing out.”
One of the promising ways we can get at a more complete definition of meditation is to look at what is happening in the brains and bodies of people from different meditation traditions when they are doing their practice and see what is similar and what is different. It may be that all meditative activity looks the same to the brain. Or we may find that certain practices engage specific parts of the brain and this is why they are suited to developing particular latent potentials of the mind.
Recently modern science has developed sophisticated tools to explore meditative practice for clues to how it affects our body and brain. And what they have been finding sheds new light on the power of meditation to make a measurable difference in our experience of the world. Even though there is a wide variety of studies being done these days, following a number of different approaches to meditation, the general trend of this research shows that we can exercise some degree of control over things we didn’t think we could change. The scientific study of meditation shows that once we break through our preconceived notions about human capacity, new possibilities for self-transformation abound.
Recently modern science has developed sophisticated tools to explore meditative practice for clues to how it affects our body and brain. And what they have been finding sheds new light on the power of meditation to make a measurable difference in our experience of the world.
Controlling the Body
Some of the first scientific experiments that explored this possibility were performed in the late 1960s at the Menninger Foundation in Topeka, Kansas, under the direction of Elmer and Alyce Green. The Greens did not focus on meditation per se, but on the voluntary regulation of physical processes that were presumed uncontrollable. Their method was to teach people to master bodily functioning through the use of biofeedback training. Test subjects were hooked up to a variety of gadgets, including electroencephalographs (EEG) to measures brain waves, electrocardiographs (EKG) to measure heart rate, as well as devices to measure skin temperature and breathing rates. These were connected to lights or sounds that went on and off when certain physical measures were met. By learning to trigger a light or a sound, the subjects were able to gain control over physical processes such as heart rate and blood pressure. Some were even able to control blood flow to mitigate migraine headaches.
About this time Swami Rama had arrived in the United States with the intention of bridging Eastern and Western understandings of the body and mind. Working in collaboration with scientifically trained psychologists and medical doctors, he made his way to the Greens’ laboratory where he demonstrated remarkable control over his states of consciousness and physical processes. While connected to an EEG, for example, he was able to produce the four prominent bands of brain waves (beta, alpha, theta, and delta) at will and for prolonged periods of time. He was also able to produce delta waves—which typically indicate deep sleep—while remaining aware of conversations and events in the room around him. And by exercising mental control over the arteries in his hand, he was able to create a 10-degree difference in temperature between the right and left sides of his palm.
But his most important demonstrations involved control of the heart, an organ long thought to be beyond conscious regulation. Swami Rama had stopped the flow of blood from his heart for physicians before, but no scientific instruments had ever been used to observe what was going on inside his body when he did. The Greens hooked him up to an EKG, which showed his heart rate at a steady 70 beats per minute prior to the experiment. When Swami Rama “stopped” his heart, the machine reacted violently, showing a heart rate of 300 beats per minute. This created a condition known as atrial flutter in which the heart beats too fast to move blood through its chambers. The EKG recorded 17 seconds of atrial flutter, during which the blood in Swami Rama’s body stopped flowing. When he returned his heart rate to an even 70, the blood started flowing again and he showed no adverse effects from the experiment.
While some capacity to regulate heart rate had been demonstrated in laboratory animals as early as 1965 and some work had been done to train cardiac patients to stabilize their heart rate, nothing like Swami Rama’s level of control was expected or even considered possible by the scientific community. He explained his capacity for self-regulation with the seemingly simple observation, “All of the body is in the mind, but not all of the mind is in the body.” But Swami Rama was not meditating when he raised his heart rate nor when he produced different brain waves for the EEG. He was merely exercising control over his body (and brain) gained through the physical practices of yoga and by plumbing the depths of consciousness in meditation.
Serious investigation of meditation was not possible in the early ’70s. The available technology could chart the effect of the mind on the body through measurements of breath, heart rate, and body temperature, but exploring the structures and function of the brain remained largely inaccessible to science.
Mapping the Mind
Over the past 30 years the technology for studying brain activity has improved dramatically. Modern EEG sensors are now incorporated into snug-fitting caps that can take readings from up to 256 positions around the head. This provides a detailed picture of which parts of the brain are active during different mental activities like talking, seeing, and concentrating. EEG is particularly useful for meditation studies because it is physically non-invasive and doesn’t interfere with the practice. It also gives a detailed account of changes in brain activity on a second-to-second basis, so it is easy to correlate the objective data with what a test subject reports as subjective experience during the experiment. The downside of EEG is that, even with 256 sensors, it lacks the precision necessary to trace the complex interaction of neurotransmitter systems.
Brain activity is a complicated synchronicity of chemical and electrical activity. To study the chemical aspects of brain function, scientists turn to imaging techniques that focus on the blood flow in the brain such as functional magnetic resonance imaging (fMRI) and scans that detect radioactive chemicals injected into the bloodstream of a test subject. These methods provide precise views of brain activity and offer insight into the function of specific parts of the brain, but they tend to be cumbersome and can get in the way of meditative practice. Functional magnetic resonance imaging scanners, for example, require a test subject to lie down in an enclosed space, and they can make up to 100 decibels of noise. To get some idea of how distracting this might be, imagine trying to meditate with a crying baby in the room or on a subway platform when a train is approaching. Even so, some studies use both EEG and the more sophisticated brain imaging techniques like fMRI to get a more comprehensive understanding of the brain’s activity.
Sophisticated technology itself is useless without researchers who can study meditation from a scientific perspective while taking seriously the traditional understanding of meditation as a powerful tool for developing latent human potentials. One of the most influential among the new generation of scientists who are interested in meditation is Richard Davidson, director of the Keck Laboratory for Functional Brain Imaging and Behavior at the University of Wisconsin. His interest in meditation is neither recent nor incidental to his work. It began in earnest when he took a year off graduate school to travel and learn meditation in India. It continues to this day.
Sophisticated technology itself is useless without researchers who can study meditation from a scientific perspective while taking seriously the traditional understanding of meditation as a powerful tool for developing latent human potentials.
Davidson works with respected teachers of meditation, mostly in the Buddhist traditions. He has collaborated on research with Jon Kabat-Zinn and has hosted the Dalai Lama at his Madison Laboratory. Davidson sums up the situation simply: “Buddhist monks have known for centuries that meditation can change the mind. Now we are inspired by His Holiness (the Dalai Lama) to examine with our technology the precise brain changes that occur with practice.”
Scientists call the brain’s capacity to change neuroplasticity. Until very recently, it was thought that our personalities were relatively fixed by the time we reached adulthood. But a wealth of research on neuroplasticity shows that the neural networks that determine our experience of the world are in a continual state of flux. Moreover, the structure of the brain changes dramatically in response to training and experience. This change is ongoing throughout life, which suggests that you can indeed teach an old dog new tricks.
Davidson’s ongoing research is oriented practically, and he has recently been involved in a series of studies that ask how meditation can influence our emotions and the way we react to real-life experiences. His larger goal is to take specific meditative techniques and find ways to apply them to improve mental and physical health. One of his most interesting studies involves a comparison of the brains of experienced and novice meditators.
Until very recently, it was thought that our personalities were relatively fixed by the time we reached adulthood. But a wealth of research on neuroplasticity shows that the neural networks that determine our experience of the world are in a continual state of flux.
Davidson and his colleagues took EEG readings of eight long-term Buddhist meditators and ten college students who had been trained in a meditative practice for developing “unconditional loving-kindness and compassion.” In training for the study, the students were asked to bring to mind someone they cared for and respected and get familiar with the feeling of love and compassion they had for that person. After that feeling became distinct, they were asked to extend it to “all sentient beings without thinking specifically about anyone in particular.” In the study itself, both the long-term meditators and the students were asked to generate an all-embracing feeling of love and compassion.
The researchers were looking for a change in brain function during the practice as well as long-term effects of such practices on the brain when the test subjects were not practicing the loving-kindness meditation. To test for this, baseline levels of brain wave activity were established for each subject from EEG recordings of four 60-second blocks of normal, non-meditative resting activity. The brain wave activity of the subjects was then recorded as they generated feelings of loving-kindness and compassion in four separate blocks of 30 seconds of resting activity followed by 60 seconds of meditative activity.
In interpreting the data, the scientists looked for the presence of gamma waves (measuring between 25 and 42 Hz) and their relative proportion to slower brain waves. Gamma waves are generally understood to indicate that higher cognitive functions are taking place. And because the test subjects were seated and inactive during the experiment, the presence of a high proportion of gamma waves should indicate that their brains were “doing something” as they were generating feelings of loving-kindness.
The results showed a measurable difference in gamma activity between the established meditators and the students. Furthermore, this difference widened considerably when the subjects began their meditative practice. This in itself was not unexpected, but the scale of the differences is suggestive. Among the eight long-term meditators, the EEG recordings showed a 2-fold increase in gamma activity for three of the subjects. Five of the eight showed a 3-fold increase. Among the ten recently trained students, only two showed a significant (2-fold) increase in gamma activity.
The gamma activity in some of the long-term practitioners was the highest ever recorded in healthy human beings. No one can say whether these practitioners were drawn to meditation because their brains were wired a certain way or whether their brains changed as they developed in meditation, but the researchers did find a positive correlation between hours of practice—not age—and baseline gamma activity. This suggests that long hours of mental training were responsible for the remarkably high levels of brain activity found in these experienced meditators.
This type of research is helpful to both practitioners of meditation and to the scientific community. It is helpful to meditators because it gives us an idea of what is happening to our brains as we progress in our practice. It provides some independent evidence that our practice does actually make a difference. And this can lead to greater conviction, which is always welcome in a meditation practice. Uncertainty is one of the biggest obstacles to continued progress.
This type of research is also helpful to the scientific community because it suggests that even a small amount of meditation practice can have measurable changes in the brain and that long-term meditation practice can produce profound results. This opens a window into a broader view of human consciousness. While these studies do not address the most profound meditative practices, they do offer a solid and acceptable frame for the scientific community to start working with new models of human consciousness.
In terms of technological sophistication, the studies being done by scientists like Richard Davidson are a world away from those of the Greens, but they all reinforce the age-old belief that meditation is a potent tool for expanding our self-awareness and developing self-control. As scientific acceptance of meditation research grows, more studies will inevitably be done on refined states of consciousness and complicated meditation practices. And even though they represent considerable advances in scientific understanding, the current studies are just the beginning.
As the joint discoveries of scientists and meditators increase our knowledge of human potential, many of the limitations we take for granted are likely to fall away. Our collective conception of the possible determines what we can accomplish as individuals. But we might find ourselves in the near future doing things that we now consider unrealistic fantasies. Consider how absurd it would have seemed 100 years ago to say that we could send people to the moon or to search for water on Mars. People simply couldn’t imagine such a level of technological sophistication.
It might help to think of meditation as an internal technology that is undergoing a remarkable renaissance in this particular historical moment. Is it really possible to be the change we seek in the world (as Gandhi famously advised) by watching our breath and calming our mind? It’s an open question and a challenge for all of us who practice meditation. But science now confirms that meditation can improve our lives by giving us greater control of how we experience the world. And that is what really matters most. Ultimately, the desire to expand human potential is the common motive that keeps scientists engaged in research and meditators looking ever more deeply inward.
If you’re interested in the meeting of science and the world’s great contemplative traditions, check out the Mind and Life Institute’s website at www.mindandlife.org. The Mind and Life Institute has been bringing together open-minded scientists and meditators, organizing conferences, and publishing their findings for nearly 20 years. The Mind and Life Institute home page also features a link to Dr. Richard Davidson’s published report of the experiment described in this article.