No evidence of structural brain change following short-term meditation
New study finds no indication of structural brain change with short-term mindfulness training
New evidence revealed in the mid-20th century that the brain could be “plastic” and that experience could cause changes in the brain. Learning new skills, aerobic exercise, and balance training are all activities related to plasticity.
However, it is unclear whether mindfulness interventions, such as meditation, can alter brain structure. Some research conducted using the well-known eight-week mindfulness-based stress reduction course has suggested that meditation may actually change the structure of the brain. However, the scope and technology of this study were limited, and elective participant groups may have skewed the results.
In a new study, a team led by Richard J. Davidson from the University of Wisconsin-Madison’s Center for Healthy Minds found no evidence of structural changes in the brain after short-term mindfulness training.
The team’s recent study, published in scientific advances, is the largest and most rigorously controlled to date. In two new trials, more than 200 healthy participants with no meditation experience or mental health issues had MRI scans to measure their brains before being randomly assigned to one of three study groups: the course Eight-week MBSR, a non-mindfulness based course. wellness intervention called Health Enhancement Program, or a control group that did not receive any type of training.
The MBSR course was taught by certified instructors and included mindfulness practices such as yoga, meditation, and body awareness. The HEP course was developed as an activity similar to MBSR but without mindfulness training. Instead, HEP engaged participants in exercise, music therapy, and nutrition practices. Both groups spent more time training at home.
After each eight-week trial, all participants underwent a final MRI scan to measure changes in brain structure. Data from both trials were pooled to create a large sample size. No significant differences in structural brain changes were detected between MBSR and either control group.
Participants were also asked to self-assess on mindfulness following the study. Members of the MBSR and HEP groups reported increased attention compared to the control group, providing evidence that improvements in self-reported mindfulness can be linked to the benefits of any type of wellness intervention more broadly, rather than directly. be specific to the practice of mindfulness meditation.
So what about the previous study that found evidence of structural changes? Since the participants in this study had sought out a stress reduction course, they might have had more room for improvement than the healthy population studied here. In other words, according to the lead author of the new study, behavioral scientist and first author Tammi Kral, “simply choosing to enroll in MBSR may be associated with increased benefit.” The current study also had a much larger sample size, increasing confidence in the results.
However, as the team writes in the new paper, “it may be that it is only with much longer training duration, or training explicitly focused on a single form of practice, that structural modifications will be identified”. While structural brain changes are found with physical and spatial training, mindfulness training covers a variety of psychological domains like attention, compassion, and emotion. This training engages a complex network of brain regions, each of which can change to different degrees in different people, making overall changes at the group level difficult to observe.
These surprising results ultimately underscore the importance of careful scrutiny of positive results and the need for verification through replication. Additionally, studies of longer-term interventions as well as those focusing solely on meditation practices may lead to different results. “We’re still in the early stages of research into the effects of meditation training on the brain, and there’s still a lot to discover,” says Davidson.
This work was supported in part by the National Institutes of Health (grants P01AT004952, P50-MH084051, R01-MH43454, T32MH018931, P30 HD003352-449015, and U54 HD090256), the Fetzer Institute, the John Templeton Foundation, and a National Academy of Education / Spencer Foundation Postdoctoral Fellowship.
Reference: “Absence of structural brain changes resulting from mindfulness-based stress reduction: two combined randomized controlled trials” by Tammi RA Kral, Kaley Davis, Cole Korponay, Matthew J. Hirshberg, Rachel Hoel, Lawrence Y. Tello , Robin I. Goldman, Melissa A. Rosenkranz, Antoine Lutz and Richard J. Davidson, May 20, 2022, Scientific advances.