The article looks at mindfulness mediation, a practice that involves becoming aware of experiences in the present moment without judging oneself. Many studies have already shown that mindfulness-based stress reduction programs can ease symptoms of anxiety and depression and can improve sleep and attention. But how does it work? To answer this question, researchers studied what mindfulness meditation does to your brain (to learn about what mindfulness mediation does to your pain, see this post).
The study looked at a handful of participants enrolled in an 8-week Mindfulness-Based Stress Reduction course. This course entails one meeting per week, one full day of training in week 6, and daily homework to do at home (meditation exercises). The experiment was very simple: researchers took a picture of each participant's brain using magnetic resonance imaging (MRI) at two time points: before the course started, and once it was over (8 weeks later). They also took pictures of the brains of control subjects who didn't take the course (also about 8 weeks apart).
By now I'm sure you've guessed the results: yup, the participants who meditated had significantly bigger brains. One area of the brain in particular was bigger: the hippocampus, a region known for its role in memory, but also involved in emotions. The researchers hypothesized that the increase in gray matter in the brain of people who mediate may explain the improvement they experience in dealing with their emotions. This hypothesis is supported by the fact that people who suffer from certain emotion-related diseases and disorders like depression and post-traumatic stress disorder often have a smaller hippocampus.
While I'm a big believer in meditation (this blog is so biased!), there are two limitations of this study worth mentioning. First, the researchers only looked at about 14 participants in each group. That's a pretty small sample, so it will be interesting to see what later experiments looking at more subjects come up with. Second, the mindfulness-based stress reduction program is not only about meditating: it also involves social interaction at the weekly meetings, stress education, and gentle stretching, which the control participants didn't get. So it's quite possible that the effect described here (bigger brains) are not the result of meditation per se. At this point we can't tease it out.
Regardless of these limitations, though, the study drives home an important message: the adult brain can change in response to training. I for one find some comfort in that.
Reference: Mindfulness practice leads to increases in regional brain gray matter density. (2011) Holzel BK et al. Psychiatry Research: Neuroimaging, 191:36-43.