July 28, 2011 – Meditation could increase the connection between different parts of the brain. It would thus reduce the cerebral atrophy associated with Alzheimer’s disease, observed in aging people.
American researchers1 made this discovery by comparing the brain activity of followers of meditation to that of people who did not practice it2.
Their trick? Use a magnetic resonance imaging technique that visualizes bundles of nerve fibers in the brain, scientifically called “diffusion tensor imaging”.
More white matter, for longer
The researchers were then able to observe significant differences between the two groups in the white matter of the brain. White matter is made up of bundles of nerve fibers that connect different parts of the brain to each other in order to transmit nerve signals.
Thus, the brains of people practicing meditation not only exhibited more bundles, but the bundles were also denser.
To make an analogy, we could say that the harnesses are like electric wires. In people who meditate, the threads are more numerous and stronger. They thus ensure a greater connection between the different parts of the brain.
The most marked differences were observed in three places: in the corpus callosum, which connects the two hemispheres (left and right) of the brain, in the pyramidal tract, which connects the brain to the spinal cord, and in the unciform bundle linking the frontal lobe (the front part of the brain) to the limbic system (seat of emotions).
Even more, the researchers also observed that the normal – age-related – decline in the amount of white matter was less in people who meditated than in others.
Two hypotheses: the innate or the acquired?
How to explain these observations? Two hypotheses are suggested. On the one hand, meditation could provide benefits to the immune system, which would promote the development and maintenance of white matter or, at least, reduce its decline.
On the other hand, it is also possible that people who practice meditation have, at their core, different brains from others. They could indeed be endowed with a greater connection of bundles of neural fibers, which would make them more receptive to this type of mental exercise.
Further studies with a larger number of participants and over a long period of time will be necessary to accurately determine the part of innate and acquired in the increase in neural connection observed in meditation practitioners.
Louis M. Gagné – PasseportSanté.net
1 Luders E, Clark K et al. Enhanced brain connectivity in long-term meditation practitioners. Neuroimage. 2011 June 6.
2. The study compared a group of 27 adults practicing a form of meditation for 5 years to 46 years to a control group, identical in terms of sex, average age (52 years) and level of education. , which also consisted of 27 participants.
