Science on Meditation and Your Brain
What monks know—and we can learn—about the fruits of meditation. A special report on the latest research from scientists who also meditate.
The images of monks with electrodes taped to their scalps were startling when they first appeared. Today, the ancient practice of meditation, begun in Vedic times, is attracting the attention of a growing community of scientists—and not all their study subjects wear robes. Meditation has gone mainstream: Millions of Americans practice some kind of meditation—among them school children, executives, cancer patients, prisoners, sports teams. Even many of the scientists themselves are meditators, for without a first-person experience of meditation, they say, it would be hard to design high-quality studies or even identify which questions are the right ones to ask.
As I meditated, I realized that what I was actually doing was training my attention,
Amishi Jha, a neuroscientist who studies attention and memory, took up meditation as a way to handle the stresses of life as a mother of two young children, with a faculty position at an Ivy League university. “As I meditated, I realized that what I was actually doing was training my attention,” Jha says. “It was really an aha moment as a scientist.” She decided she could use her scientific techniques and paradigms to discover what exactly was happening in the brain during meditation.
Jha is not alone. Scientists are using increasingly sophisticated high-tech tools—imaging of the functioning brain, for one—to learn what effect meditation has on the brain, on psychological distress, and on the physical symptoms of illness. In all cases they are finding that meditation leads to profound improvements in functioning.
One particularly interesting body of research has focused on mindfulness meditation, though researchers recognize that other forms of meditation may produce different or more significant changes in the brain and body. Part of the reason for the interest in mindfulness meditation, says Philippe Goldin, PhD, a clinical psychologist and meditation researcher at Stanford University in California, is that in 1979 Jon Kabat-Zinn, PhD, developed a specific eight-week course called Mindfulness-Based Stress Response (MBSR). The standard MBSR course encompasses formal meditation sitting with a focus on the breath, walking meditation, body scans in which participants observe their own physical sensations, eating meditation, and hatha yoga. Students also participate in weekly discussions and lectures, and commit to a daily home meditation practice.
More than 15,000 students have completed the course at the Center for Mindfulness in Medicine, Health Care, and Society, which Kabat-Zinn founded, and thousands more have taken the course elsewhere. With that long-standing experience, scientists know that the MBSR program is effective, and the consistency of the approach enables them to compare results between studies and over time.
Rewiring the Brain
In Jha’s first study on meditation and the brain, which will be published next month in Cognitive, Affective, & Behavioral Neuroscience, she found that mindfulness meditation improved study volunteers’ ability to focus their attention. Seventeen people with no prior experience in meditation completed a series of computer tasks before and after the MBSR course.
The tasks probed three neurological systems in the brain that control different aspects of attention. The systems are called alerting, orienting, and conflict monitoring, and they correspond, respectively, to one’s readiness to pay attention to something, one’s ability to direct attention to that object, and one’s ability to focus on something in the presence of distractions. After completing the MBSR course, the volunteers were faster at orienting their attention than they were before it. They showed no improvement in computer tasks that relied on either the alerting or conflict monitoring realms of attention.
By contrast, when Jha challenged experienced meditators before and after a month-long meditation retreat with the same computer tasks, she found that their alerting system improved. “They got better at their readying capacity of attention,” Jha says. “They could keep their attention in a much more neutral state without knowing what they were to engage in.”
Contrary to what many meditators might expect, Jha didn’t find that meditation improved the volunteers’ ability to sustain their attention. “What we think might be happening,” she says, “is that even though the subjective experience is one of sustaining continual attention for a longer period of time, this experience may be a consequence of improvements in the moment-by-moment orienting of attention without being distracted away.”
Of course, Jha is not alone in her efforts to find out what is going on under the scalp during and after meditation. Antoine Lutz, PhD, and Richard Davidson, PhD, of the University of Wisconsin in Madison, made headlines three years ago when they reported that the electrical activity in the brains of Buddhist monks was significantly different from what was seen in meditation novices.
During the study, the monks were asked to enter a meditative state of pure compassion while wearing a cap with 128 electrodes on their heads. The resulting electroencephalogram (EEG) illustrated that the monks had high amplitude gamma waves, which are a particular type of brain wave that occurs when physically separated neural networks work together to process information. Thus these long-term meditators have somehow learned how to turn on coordinated activity in multiple brain regions.
More remarkable, perhaps, Lutz says, is that there seemed to be both short- and long-term differences between the monks’ gamma waves and those of novice meditator control subjects, which suggests that meditation can induce lasting changes in the brain. “The interesting thing is that meditators not only want to reach some state during meditation, but they also want to transform themselves, meaning that after a period of meditation you want to be somehow behaving differently and have a different way to experience emotions,” Lutz says. The brain changes that showed up in the monks, when compared to controls, suggest that those changes are happening—and at the level of brain wiring.
Changing Thinking Patterns
In addition to examining meditation’s impact on brain activity, scientists and clinicians want to know what impact it has on a person’s psychological health and well-being. And though individual meditators may say they feel better as a result of meditation, only carefully designed scientific studies can help pin down who benefits from such practice and what those benefits really are.
One of the most important studies in this area was done by Zindel Segal and John Teasdale at the University of Toronto. They reported that a combination of cognitive therapy and mindfulness meditation halved the risk of relapse in patients with a history of three or more episodes of major depression.
The likely explanation for this dramatic risk reduction is that individuals with a history of depression are extremely vulnerable to negative thinking. Such thinking can trigger a spiral into another depressive episode. Mindfulness training takes away some of the power from those thoughts by allowing individuals to see that they are only thoughts or memories, not facts, and that they are only part of a larger experience.
“Time and again, mindfulness-based stress reduction has been shown to be very helpful in reducing symptoms of anxiety, depression, and experience of physical pain,” says Stanford researcher Goldin. “It gives people specific skills to be with whatever is happening and not add on layers of thinking, interpreting, and habits that actually enhance the psychological imbalance.”
Goldin himself came to meditation while studying in Nepal during his junior year of college. While there, he spent time living in monasteries, learning Sanskrit and Tibetan Buddhist philosophy. “And most important,” he says, “I was meeting many different teachers who just through their example showed me that their mind was more free and unencumbered than mine…through meditation practice.” When Goldin came back to the United States and embarked on a career in clinical psychology and neuroscience, he brought the meditation skills with him.
Exercising the attention “Muscle”
In his current research, Goldin has been testing the effect of MBSR and cognitive-based therapy in patients with social anxiety. People who suffer from social anxiety disorder, which is also called social phobia, have an intense fear of negative evaluation by other people, they fear humiliating or embarrassing themselves in performance or social situations, and can have trouble forming close relationships or even leaving the house. Goldin finds that patients who participate in a modified MBSR course, which takes nine weeks and integrates cognitive skills as well as mindfulness meditation, feel a relief of their symptoms and do better on diagnostic tests.
To find out what is happening at the level of neurobiology, Goldin gives them a series of challenges and exercises while they are lying in a magnetic resonance imaging scanner. The functional MRI (fMRI) images show how much blood is flowing to different regions of the brain, which is indicative of how hard an area is working. In these tests, which he conducts before and after the nine-week course, Goldin first triggers the participants’ anxiety with images or verbal cues. Then he asks them to either try to regulate their emotions through self-talk aimed at reducing the intensity and credibility of the trigger, or by mindfulness meditation with a focus on the sensation of their breath at the tip of their nose.
When he looks at the pictures that were taken at different points in the exercise, he finds that the amount of activity in different regions of the brain shifts substantially. When the participants first experience the trigger, without making an effort to control it, activity is high in the limbic regions of the brain, which encode fear and other emotions. After mindfulness training, however, when they shift their attention to their breath, the brain activity shifts to the networks involved in attention—the same ones that Jha studies. Moreover, they were more adept at using self-talk strategies to reduce activity in the limbic regions. “This is promising. It is like when you use a muscle for three months and it becomes stronger and bigger. These people are using the muscle of attention,” he says.
Iraq Vets Learn Yoga Nidra
Meanwhile, Richard Miller, PhD, of the Center of Timeless Being in Sebastopol, California, has been working at the Walter Reed Army Hospital in Washington, DC, with war veterans who have post-traumatic stress disorder (PTSD). Miller teaches the soldiers a guided meditation practice, called yoga nidra, which encompasses physical, emotional, and mental relaxation; observation; and acceptance. The 18-session course spans 10 weeks and includes daily home practice with recorded guidance.
In a small pilot study with a handful of volunteers, Miller saw promising results. Five soldiers completed the course and the post-training evaluation. All showed dramatic decreases in stress. Miller points out that the results of the pilot study need to be interpreted with caution because there were so few participants. The results did make people take notice though, and he already has Department of Defense support to start a randomized controlled trial with 200 soldiers to see if the approach will pan out in a larger group.
When the soldier climbed into the MRI machine, he experienced a vivid flashback and bolted from the room. After attending a yoga nidra session, he was able to focus his breath, do yoga nidra—and finish the test.
Several of the soldiers from the pilot study told Miller that the skills were noticeably helpful. In one case, a soldier had to undergo an MRI for evaluation of clinical issues not related to the yoga nidra or PTSD. When he climbed into the machine he experienced a vivid flashback, which is a common symptom of PTSD. The soldier bolted from the room and felt totally defeated. However, after attending a yoga nidra session later in the day he decided to try again. This time he focused on his breath and did yoga nidra while in the scanner and was able to finish the test. He left feeling victorious.
“That is how they are using it,” Miller says. “They are learning how to use it in the midst of their life.”
A self-directed meditation practice is not advisable for anyone suffering from serious psychological distress, however. Goldin cautions that not everyone nor all conditions will benefit from meditation. He says he would be concerned about introducing meditation to someone in the midst of a depressive episode. Self-focused attention may enhance rumination, he says, and because the quality of such an individual’s thoughts are so negative, more harm than good might come from such an experience.
Rather, he would prescribe asana at such a time because it will get a person off the couch and active—which is known to help break the cycle of depression and looping thoughts. Once someone has regained a healthier mood, then meditation might be the right thing. “It is super important to do more research to know what kind of problems benefit from which kind of practice.”
Effects on the Body, Too
Numerous clinicians have found that meditation helps with physical ailments as well. For example, Kabat-Zinn found that patients with psoriasis healed almost four times more quickly if they used a combination of standard ultraviolet light therapy and meditation.
Linda Carlson, PhD, a clinical psychologist at the University of Calgary, and her colleagues regularly use MBSR with cancer patients and have found that the practice improves both subjective and objective measures of health and well-being. “We’ve found a huge effect,” Carlson says, “on symptoms of stress, anger, muscle tension, digestion, sleep, anxiety. We were surprised at the size of the effect. It was quite a bit bigger than research on a lot of other interventions shows.”
Recently the team has looked at the impact of MBSR on blood pressure in women cancer patients, most with breast cancer. They found that in women with high blood pressure, the training led to drops in pressure that were similar to when a patient is put on medication. In other words, the women’s blood pressure dropped from slightly above normal into the normal range—without pharmaceutical intervention.
Numerous groups have also seen improvements in immune system functioning after MBSR training. Carlson thinks that the adjustments reflect a re-balancing of internal rhythms that get out of whack during episodes of illness or disease. By meditating regularly, the patients seem to be able to restore that balance and strengthen their own physical and mental defenses.
For Jha, her work studying the brain adds an extra layer of challenge to letting go during her practice. “Because I think so much about it in my normal non-meditating life, about what are the mechanisms of these effects, when I am actively practicing it is hard not to wonder about what might be happening.”
For the rest of us, interesting as all these findings may be, we have simply to turn our attention to our breath and begin to reap all the benefits.
Rabiya S. Tuma, PhD, is a biologist. She is a regular contributor to the Dana Alliance for Brain Initiatives and writes frequently on brain research.