July 14, 2011

Science Daily/University of California - Los Angeles

Researchers have found that long time meditators have stronger connections between brain regions, and show less age-related atrophy when compared to a control group. 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.

Two years ago, researchers at UCLA found that specific regions in the brains of long-term meditators were larger and had more gray matter than the brains of individuals in a control group. This suggested that meditation may indeed be good for all of us since, alas, our brains shrink naturally with age.

Now, a follow-up study suggests 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.

Results showed pronounced structural connectivity in meditators throughout the entire brain's pathways. The greatest differences between the two groups were seen within the corticospinal tract (a collection of axons that travel between the cerebral cortex of the brain and the spinal cord); the superior longitudinal fasciculus (long bi-directional bundles of neurons connecting the front and the back of the cerebrum); and the uncinate fasciculus (white matter that connects parts of the limbic system, such as the hippocampus and amygdala, with the frontal cortex).

"It is possible that actively meditating, especially over a long period of time, can induce changes on a micro-anatomical level," said Luders, herself a meditator. 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," Luders said. "That is, if practiced regularly and over years, meditation may slow down aging-related brain atrophy, perhaps by positively affecting the immune system."

"It's possible that meditators might have brains that are fundamentally different to begin with," Luders said. "For example, a particular brain anatomy may have drawn an individual to meditation or helped maintain an ongoing practice -- meaning that the enhanced fiber connectivity in meditators constitutes a predisposition towards meditation, rather than being the consequence of the practice."

Still, she said, "Meditation appears to be a powerful mental exercise with the potential to change the physical structure of the brain at large. Collecting evidence that active, frequent and regular meditation practices cause alterations of white-matter fiber tracts that are profound and sustainable may become relevant for patient populations suffering from axonal demyelination and white-matter atrophy."

http://www.sciencedaily.com/releases/2011/07/110714091940.htm