Meditation, White Matter & Aging

Mindfulness is the act of focusing one’s attention on the present moment without judgement. This can be achieved through formal meditation or by simply bringing attention and awareness to the present moment during day-to-day activities. The benefits of mindfulness are far reaching - from decreasing stress, anxiety, and depression, to boosting focus, memory, problem solving. In addition to these functional benefits, there is also some evidence that mindfulness affects the structure of the brain. Studies have shown that meditation is associated with a higher concentration of grey matter in certain areas of the brain. However, the impact of mindfulness and meditation on white matter is less understood.

Unlike grey matter, which is composed of neuron cell bodies, white matter is composed of neuron axons, which connect different regions of the brain to one another. Therefore, white matter is incredibly important for cognitive function. Myelin is a fatty substance that wraps around these axons and is what gives it its white appearance. Myelin protects these axons like the bark on a tree and allows for quicker transmission of messages between neurons. White matter has been shown to be positively affected by exercise and eating a diet rich in healthy fats. However, white matter volume and integrity naturally decrease with age. Therefore, Laneri and colleagues aimed to elucidate the impact of mindfulness and meditation on the age-related decline of white matter.

The researchers recruited 33 healthy individuals from Buddhist and Zen centres in Germany. All of them practiced meditation regularly and had at least 5 years of meditation experience. They also recruited 31 healthy individuals who had no experience with meditation. They focused on five regions of the brain that have been found to be activated differently in meditators: the anterior cingulate cortex, the insula, the amygdala, the thalamus, and the hippocampus. In these areas, the researchers used fractional anisotropy (FA), a diffusion tensor imaging technique that is a good indicator of white matter integrity and connectivity.

Laneri and colleagues found that the meditators had higher FA values in several regions of the brain, including the thalamus (responsible for relaying sensory information to the brain), the insula (important for body awareness), and the amygdala (responsible for emotion regulation). This is consistent with studies that have found increased activation in these areas of the brain during meditation. Additionally, there was a typical decline in FA with age in the control group but not in the meditators in almost all of the brain regions. This suggests that mindfulness meditation could help slow the aging process by preserving white matter.

Figure from Laneri et al. 2016. The control group displayed a typical decline in white matter integrity in the left insula with age, whereas the meditators did not.

Aging is associated with a gradual decline in cognitive function, which is thought to be partly due to white matter degeneration. This study is promising as it suggests that mindfulness meditation could help prevent or slow this age-related decline and preserve brain structure and function. The researchers suggest that longitudinal studies are needed to determine cause and effect and that the optimal meditation techniques to preserve white matter integrity have yet to be determined. However, these results imply that mindfulness practices can attenuate the white matter degradation and associated cognitive decline in aging.

What can we take away from this research?

1. While there are many factors associated with the age-related decline in cognitive function, it appears that meditation might help preserve brain structure and function.

2. You’re never too old to start meditating! Everyone can learn something at any age and the more you meditate, the easier it might be to learn other things as well.

3. If you’ve never meditated before, just start with 5 minutes of doing nothing but focusing on your breath. Whenever your mind wanders, simply bring your attention back to your breath.

You can read the entire research article here and for more instructions on how to meditate, check out our blog on this subject!