Brain scans

Mindfulness: The Research

This story is part of a 3-part series on mindfulness.

“I think there's a natural marriage between being a psychologist and neuroscientist—being interested in how minds and brains work—and mindfulness, which is basically watching how your own mind works from the inside out,” Todd Braver, a professor of neuroscience, radiology, and psychological and brain sciences, says. “So it seemed natural to study it.”

Mindfulness is still a nascent field of study, and the research has ranged from the rigorous to the, well, bunk. Braver has a graph of the number of scientific publications that use "mindfulness" in the title. If you go up until about 1998, there are a handful of studies or fewer per year. Then suddenly as you go past 2000, the number skyrockets, so that by 2012, there are hundreds of papers coming out every year. “It's really something that's just exploded scientifically in the last two decades,” he says.

The Early Years

Jon Kabat-Zinn
Jon Kabat-Zinn

Jon Kabat-Zinn, now a professor of medicine emeritus at the University of Massachusetts Medical School, first popularized the word ‘mindfulness’ in the 1970s for a program he developed called ‘mindfulness-based stress reduction’ (MBSR). It adapted Buddhist teachings and meditation techniques, but removed the religious framework, in order to make it more accessible for Western and health environments. However, much of the early research on meditation, yoga, and other mindfulness techniques was highly flawed. Rather than having randomized studies, the early researchers were themselves practitioners of meditation and yoga and often used small sample sizes of like-minded individuals, or those who were already convinced it worked as well.

“It wasn't really high-quality science,” Braver says. “It is still the case—though it's not problematic in and of itself—that a lot of people who are doing mindfulness research engage in the practices themselves and find it personally beneficial. But I think what has changed is that the rigor and methodology of the studies has improved over the last 20 years compared to some of the earlier work.”

To Braver, this distinction between rigor and bias is one of the most important lessons he teaches his students. “We have a strong obligation to do the most careful, rigorous science that we can and not be seduced by what our beliefs are beforehand,” Braver says. “Science is about finding out the truth as best as we can, and if we come in with a foregone conclusion about what we're going to find, then that's going to influence how we do the science and our interpretations of it.”

A Buddhist monk meditates with EEG for neuroscience research
A Buddhist monk meditates with EEG for neuroscience research

Braver credits Richard Davidson from the University of Wisconsin-Madison for legitimizing the field. When Davidson first began his mindfulness research in the 1970s, he had to keep it hidden, since it was so disreputable. Major research funding for these kinds of studies would have been unheard of. However, Davidson made some astounding findings. His first published work on the topic examined the brains of Buddhist monks and found exceptional brain function characteristics compared to the average person, in terms of some brainwave patterns, and some of their responses to loud, aversive noises—how strongly their brain reacted or didn’t react.

Later, in the early 2000s, Davidson worked with a CEO of a major corporation who was interested in exploring mindfulness. Davidson taught a short eight-week intervention to a random sample of the employees. They found that those who took the course had dramatically higher brain and immune function at the end of the course than the comparison group. Braver says, “So Davidson led these studies on both world-expert monks who practice mindfulness for thousands of hours each year, achieving tens of thousands of hours of experience over their lifetime, as well as the effects observed from shorter-term interventions conducted with just your average people.”

“Science is about finding out the truth as best as we can, and if we come in with a foregone conclusion about what we're going to find, then that's going to influence how we do the science and our interpretations of it.”

Remolding That Gray Matter

Mindfulness can actually change how the brain is wired and shaped. In the early 2000s, researchers began to show that human brains are a lot more ‘plastic’ than was originally thought—even as adults—which means that brains can change their structure and function relatively dramatically. “So when you ask yourself, ‘What can you change with these kind of practices? What's the limit?’ we know that these practices can have a strong impact on brain function and structure that we hadn't appreciated before,” says Braver.

“There's been findings that show, for example, that mindfulness practices change brain volume and thickness in certain areas that are related to memory, such as the hippocampus, and in areas thought to be involved in awareness of bodily signals,” says Braver. “One of these brain areas controls what we call ‘introception,’ or your ability to detect signals going on both internally and emotionally, like, ‘Is my heart racing or not? Is my breath shallow or not?’ It's an area called the insula that's deep in the folds of the cerebral cortex. Here again the evidence has shown that you get both increases in responsivity and also increased cortical thickness in this area through mindfulness practice.”

The changes are very targeted on the specific areas that might be important for emotional and cognitive regulation, and also for attentional function. If you're interested in learning more about what mindfulness is and how one practices it, visit Part I of this series.

Cautious Optimism

For her part, Heather Rice, an assistant dean in the College of Arts & Sciences and a senior lecturer in psychological and brain sciences, wants more data. According to Braver’s graph, the explosion of mindfulness research didn’t take off until the 2000s. For all of the nuances and complexities of mindfulness, 20 years is nothing. 

“This recent explosion of mindfulness research—a lot of them aren’t the strongest of studies. There's not a lot of, for example, randomized controlled studies where you've got a group of people and half of them are randomly assigned to do meditation and half of them are randomly assigned to do something else that is similar to meditation but doesn't have what we would think of as the ‘active ingredients’ of meditation. You just don't see that kind of work very often,” she says. “So a lot of the conclusions that people are trying to make from the research that's out there, we just can't make yet. But now there is a growing body of well-designed studies suggesting that mindfulness practice can be really helpful.”

Richard Davidson
Richard Davidson

This is what Rice wants the students in her course “Mindfulness in Psychology and Eastern Philosophies” to take away: yes, there’s evidence to suggest that meditation and mindfulness practices are beneficial, but we need a lot more research—and that’s where the students can actually help. “That doesn't mean that we should stop asking questions,” she says, “but it does mean we should be informed consumers. We need more rigorous research. And now, thanks to the work of Richard Davidson and my colleague Todd Braver, this kind of research is being taken seriously and is getting funding. The rigorous studies are starting to be conducted, and they have shown that there are some reliable effects.”

She’s hopeful that these positive results can be widely replicated. “If mindfulness does improve psychological well-being, it's a relatively easy and inexpensive treatment strategy compared to many other existing therapies. It doesn't require fancy equipment. It's something that you can practice on your own. So, there’s the potential for many people to benefit from it.” 

“So a lot of the conclusions that people are trying to make from the research that's out there, we just can't make yet. But now there is a growing body of well-designed studies suggesting that mindfulness practice can be really helpful.”

Studying Mindfulness Effects in the Lab

Several years ago, when Braver first began to practice mindfulness, he found it to be a natural extension of his own research on self-control. “A lot of the mindfulness research focuses on controlling your thoughts, not letting them control you; being able to regulate your emotions; and the idea that concentration, attention, and self-control are really important elements for psychological well-being.”

Todd Braver and his graduate students
Todd Braver and his graduate students

For a previous experiment, he and his group had developed a battery of experimental tasks that tapped into dimensions of control, and they were beginning to pinpoint the brain basis of those functions as well as metrics for comparison. In order to best isolate the individual differences between brains, Braver and his group decided to study identical twins. Twins are ideal to study because genetically, they are the same, and often their strengths and weaknesses are very similar. However, their brains can be different, given that even slightly different life experiences will modify the brain structure and wiring in different ways. Braver and his group were excited to compare two brains that started the same but diverged along the way in order to pinpoint the exact areas of the brain that change due to experience. “And since we had this group of individuals that had been already randomly selected from the population,” Braver says, “I thought we could use it as an opportunity to do a nice mindfulness intervention.”

So Braver is scanning the twins’ brains again, after having one member of the twin pair participate in an eight-week-long mindfulness-based stress reduction intervention. Each twin is scanned twice, in order to look for any before and after differences, as well as any differences between the two twins. (The other twin will be able to take the intervention too, but once the study is over.) “If the twins start to diverge from each other in the cognitive control functions that we are measuring, it would help us confirm that it is the increased practice and exposure to mindfulness that might be causing the changes in brain function,” he says. “The goal is to do the research in a way that is more careful and controlled than some of the work that's been done previously.”

Research in the Classroom

Braver is also conducting a second study with the participants of his first-year seminar course, who are encouraged to practice mindfulness as they learn about it. “The original idea for the course was to combine two things that interest me: the practical side of teaching people these mindfulness skills and the scientific side of how we actually go about studying what's happening and then evaluate the results,” he says. “So basically we assess ourselves at the beginning of the class, and throughout the semester, and then once more at the end of the class. During the semester, we talk about what are we looking for and what are some things that are useful to assess. I’m collecting data, and they're collecting data on themselves, and then we're talking about how we use this data. The students get to be experimenter and participant at the same time.”

Though there are self-report scales for what is called “trait mindfulness,” Braver and his class are also trying out a new, potentially more accurate measure. Richard Davidson and his group recently found that those who were able to more accurately count their breaths also had higher levels of happiness, positive mood, and overall psychological well-being. “Being able to focus on your breath, to control your attention, is one of the skills that gets practiced in mindfulness,” Braver says. “Breath counting provides an objective measure, and mindfulness training has been shown to increase counting accuracy.”

Richard Davidson and his group recently found that those who were able to more accurately count their breaths also had higher levels of happiness, positive mood, and overall psychological well-being.

In order to find a control group, Braver teamed up with his colleague Tim Bono, who teaches a first-year seminar of his own called “The Psychology of Young Adulthood.” In this course, Bono has similar goals of helping first-year students develop skills and training for their life ahead, including some discussion of mindfulness, though they do not practice it as much as Braver’s group. “It seemed like they were a good comparison group because they were the same age, they were people who were likely to be interested in the same kinds of topics or else they wouldn't have signed up for the seminar, and they're going through a similar life stage, transitioning into their first year at WashU,” Braver says. “Bono had already also done some assessments on how the class was affecting his students, so we began to do the same assessments before, during, and after the course, and that was how we compared our groups.”

Braver is quick to admit that these data aren’t the cleanest. There was only so much experimental control they could impose with the students, and it was the first time he and his graduate student, Catherine Tang, were using certain assessment tools. Furthermore, classes are kept to a small size in order to keep it more intimate, but that means the sample size isn’t very big. Braver says, “So I would say some of our findings, I think they're a good indicator of what potential is there, but they're not as strong as we might have thought they would be. But there are still some promising patterns here.”

“The most interesting thing we found was that this measure of ‘trait mindfulness’ strongly increased in the people in our course relative to Bono's course. We also found a significant reduction in anxiety in our class, and we found evidence of subtle effects in improved attention and working memory, or the ability to hold information in mind over a delay when there is distraction, in our class,” Braver says. He and his graduate student will be gathering more data this semester, trying to improve upon their methods from last time. Both of these studies will offer valuable new information to help us better understand—and document—the effects of mindfulness.


If you're interested in reading more about what mindfulness is and how one practices it, visit Part I of this seriesIf you're interested in exploring more about the overlap between religion and science in mindfulness, visit Part III of this series. Or return to the series homepage