The many benefits of meditation on our brain

The Belgian neurologist Steven Laureys, who is recognized worldwide for his studies on the state of consciousness of comatose patients, initially considered meditation with skepticism, seeing it first as a “fad”. But when an event turned his life upside down, it was yoga and the discovery of meditation that helped him. His scientific mind then prompted him to explore the effects of mediation on the brain, and what he discovered convinced him of the benefits of this mental gymnastics. This even led him to prescribe it to his patients suffering in particular from pain, anxiety, depression, and even insomnia in addition to conventional treatments.

In his research laboratory at the University Hospital of Liège, in Belgium, Dr.^r Laureys used different brain imaging techniques to study the brain of famous Buddhist monk Matthieu Ricard. His team found that the structure and functioning of the brain of this expert in meditation was clearly different from those of other people who are old, like him, over 70, but who do not meditate. In addition to publishing several scientific articles relating his discoveries, Dr.^r Laureys wrote: Meditation is good for the braina book published by Odile Jacob, in which he popularizes everything we have learned about the effects of meditation on the brain and health.

More specifically, the Liège researchers observed, using magnetic resonance imaging (MRI), a thickening of the gray matter of his brain in brain regions orchestrating the control of attention (anterior cingulate cortex). , the perception and regulation of internal signals and stimuli coming from our own body, including pain (insular cortex), memory (hippocampus), emotional control (amygdala) and decision-making (prefrontal cortex).

“Grey matter volumetrics [qui se compose des cellules nerveuses ou neurones] by Matthieu Ricard appeared to us to be similar to that of people 10 to 15 years younger than him,” remarks Dr.^r Laureys, while recalling that our gray matter decreases as we age. “Meditation does not immunize us against dementia, it will not cure us of this disease, but we see that it has a visible impact on the brain. This is why, within the framework of European multicentre studies, people who are at risk of developing neurodegenerative diseases, such as Alzheimer’s, are offered an eight-week program of mindfulness meditation called “Reduction of stress based on mindfulness” (Mindfulness-Based Stress Reduction, MBSR),” he says.

Development of neural networks

Using diffusion MRI, which measures the white matter (which is mainly made up of axons, the wires that connect neurons together) in the brain, the D^r Laureys also noted in Matthieu Ricard and other meditation experts a densification of the corpus callosum, this bridge which connects the two hemispheres of the brain. “A denser corpus callosum means there are more interhemispheric connections. But a better connected brain is also more efficient,” explains Dr.^r Laureys.

These observations, which have been made in other experienced meditators and by other teams of scientists, show that mental training through meditation increases the development of certain neural networks and connections thanks to the neuroplasticity of the brain. Even in novices who meditated for 20 minutes a day for eight weeks, changes in brain structure and function were detected, resulting in “positive effects on emotions and The behaviour “.

The D team^r Laureys was also able to highlight Matthieu Ricard’s ability to modify his brain activity through the power of meditation, an ability that had not been observed in anyone else before. To do this, the researchers used a test they normally use to assess the consciousness of comatose patients, which involves stimulating certain areas of the brain with powerful magnetic waves, while measuring the electrical activity of the brain by electroencephalography (EEG).

“The complexity of the disturbances induced on the EEG by this transcranial magnetic stimulation (TMS) determines the capacity of the brain to have a content of consciousness. During slow and deep sleep, as well as during anesthesia, this complexity is very low, while during dreaming, it is higher,” explains Dr.^r Laureys. “This response to TMS that is recorded by the EEG is a reaction that you cannot influence, it is like the patellar reflex that you trigger by a little hammer blow at the base of the knee. However, Matthieu Ricard managed to modify this answer. He could increase or decrease the complexity of the response depending on the meditation exercise he was doing. When he performed classical meditation, an increase in complexity was measured, and when he was asked to think of nothing, to enter a cognitive state as reduced as possible, he succeeded in reaching a temporary pseudocomatose state and the complexity response to TMS decreased. »

Increased focus

The researchers also subjected Matthieu Ricard and his fellow monks to tests aimed at measuring their attention spans, and they found that these meditation experts obtained scores similar to those of young academics in their 20s. They made fewer mistakes and were faster than people their age who weren’t meditating. “Meditation teaches us to be really focused on the task at hand, because very often we are [jusqu’à 47 % du temps, selon une étude] distracted by our thoughts,” says Dr.^r Laureys. He is also a visiting professor at the CERVO center at Laval University, where he is working to set up an international joint unit on the study of consciousness.

When Matthieu Ricard was asked to fall asleep, two minutes later his brain emitted slow waves which indicated that he was already in the slow, deep sleep phase.

When the energy consumption of his brain was measured using positron emission tomography, it was observed that the metabolic activity there was higher than that of the average person of his age.

Benefits of meditation have even been found at the chromosome level, adds Dr.^r Laureys. “When we age, the telomeres, these little tips located at the end of our chromosomes and which protect the DNA from them, shorten. We also know that stress accentuates this shortening. If the telomeres are smaller, there is a greater chance that errors will occur in the DNA of cells when they multiply, and these errors can lead to diseases, such as cancer. However, studies have shown that the telomeres of experienced meditators are longer than those of the uninitiated, and researchers have observed an increase in telomerase, an enzyme that protects telomerases, in people who practice mindfulness. “, he specifies.

However, meditation makes it possible to better manage stress, which often amplifies all the ailments and illnesses that afflict us, he points out. “Meditation also helps to change a person’s state of mind in the face of pain. It will not necessarily change your reality, but it is a very powerful tool that will allow you to experience your reality differently. »

“Meditation can also stimulate concentration, creativity, empathy, compassion, benevolence,” he continues. All in all, it can substantially improve our quality of life.

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