Researchers at UCLA had earlier found that specific regions in the brains of long-term meditators were larger and had more grey matter than the brains of individuals in a control group.
Now, a follow-up study has suggested that people who meditate also have stronger connections between brain regions and show less age-related brain atrophy.
Having stronger connections influences the ability to rapidly relay electrical signals in the brain. And significantly, these effects are evident throughout the entire brain, not just in specific areas.
Eileen Luders, a visiting assistant professor at the UCLA Laboratory of Neuro Imaging, and colleagues found that the differences between meditators and controls are not confined to a particular core region of the brain but involve large-scale networks that include the frontal, temporal, parietal and occipital lobes and the anterior corpus callosum, as well as limbic structures and the brain stem.
"Our results suggest that long-term meditators have white-matter fibers that are either more numerous, more dense or more insulated throughout the brain," said Luders.
"We also found that the normal age-related decline of white-matter tissue is considerably reduced in active meditation practitioners," added Luders.
The study consisted of 27 active meditation practitioners (average age 52) and 27 control subjects. Results showed pronounced structural connectivity in meditators throughout the entire brain's pathways.
"It is possible that actively meditating, especially over a long period of time, can induce changes on a micro-anatomical level," said Luders.
As a consequence, she said, the robustness of fiber connections in meditators may increase and possibly lead to the macroscopic effects seen by DTI.
"Meditation, however, might not only cause changes in brain anatomy by inducing growth but also by preventing reduction," said Luders.
"That is, if practiced regularly and over years, meditation may slow down aging-related brain atrophy, perhaps by positively affecting the immune system," added Luders.
The study is detailed in the online edition of the journal NeuroImage.