Yoga changes the brain and improves mental health

In the last decade, yoga has become fashionable, as evidenced by the proliferation of its variations, more or less credible, or the creation, in 2015, of an “International Day of Yoga”.

Many benefits are attributed to this discipline, and scientific work has sought to assess its effects on health, as well as its ability to improve the situation of patients suffering from various pathologies, such as low back pain, cancer or heart problems, for example. The consequences of practicing yoga have been studied not only in the general population, but also in specific populations: young people, people with mental illness, etc.

The results seem to indicate that doing yoga does indeed result in a variety of positive effects on physical health. This exercise dramatically improves balance, flexibility, as well as strengthening the muscles and heart. Yoga can also have a beneficial effect on the immune system, and be of interest in disease management.

What about mental health? We now know that for the latter, practicing physical activity is beneficial. Yoga is no exception. It even has a direct effect on the brain. Explanations.

Yoga improves brain activity

Yoga has the particularity, compared to other types of physical activity, of combining sequences of movements with breathing control and attention regulation exercises. In a recent meta-analysis, in other words a statistical analysis of data published in the scientific literature (an “analysis of analyses”), Chinese researchers analyzed the results of 15 scientific publications who studied the effects of yoga as well as practices belonging to the same type of “body-mind” physical activity (tai-chi-chuan or taiji, qi gong, baduanjin, wuqinxi, etc.). Among these various tasks, researchers notably used magnetic resonance imaging (MRI) to observe the effects of yoga on the brain.

The analysis of all the results of these different studies shows some improvements in the practitioners of mind-body activities, including an increase in the size of some brain regions as well in their activity. These changes primarily occur in the prefrontal cortex, hippocampus, temporal lobe, insula and cingulate cortex, structures crucially involved in emotional regulation, memory and self-control. The researchers also observed better functional connectivity in high-level brain networks, such as cognitive control (regulating attention, inhibition, working memory, etc.) and the default mode (network of thoughts and emotions of self and others).

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Another meta-analysis showed that cerebral changes observed in MRI can be correlated with behavioral changes (observed during psychological evaluations of yoga practitioners through questionnaires, observations, or interviews). How do these brain changes affect their daily lives?

Yoga reduces stress

A meta-analysis of 42 studies looked at the effect of yoga practice on stress. Stress is a biopsychological response that results specifically in physiological symptoms, negative thinking and cognitive decline. Yoga seems to contribute to stress reduction by lowering the amount of cortisol, the main stress hormone. These results remain qualified and require more in-depth studies in particular with more participants and longer interventions to judge a long-term effect of yoga on stress.

In addition to this hormonal change, other works indicate that yoga will have an effect on the activity of the frontal cortex and the parietal cortex of the brain. The frontal cortex is associated with self and emotional control, while the parietal cortex is responsible for processing and integrating sensory information.

This is explained by the fact that a yoga session is punctuated by meditative moments where practitioners must often focus on their breathing, on a specific part of their body or even on what they feel at the moment. moment . These moments of meditation will help to better regulate the activity of these brain regions, while the activity related to mental load or stress will be reduced.

Yoga improves symptoms of anxiety

Anxiety is an overflow of emotional regulation capacities that manifests itself in the symptoms of stress. It appears to be diffuse anxiety, particularly associated with difficulty concentrating and falling asleep. Depression is a psychiatric disorder characterized by a dysregulation of emotions associated with a feeling of sadness or constant hopelessness, as well as loss of interest and self-withdrawal.

Anxiety and depression are associated with a change in the activity of the amygdala, a brain structure specifically involved in negative emotions.

A meta-analysis of 27 studies conducted in children and adolescents investigated the effects of yoga on anxiety-depressive symptoms. The participants are either normal people or people with various pathologies (variant pathology, cardiac pathology, digestive disorders, etc.). This review revealed that 70% of this work showed an improvement in the mental health of young people following the practice of yoga, and more specifically anxiety, and these results were directly related to the decrease in amygdala activity. which is found in practice. adults These beneficial effects on anxiety-depressive symptoms have also been shown in adults, as well as in people suffering from anxiety-depressive disorder.

Since studies in this area of ​​research are recent, they are still few in number and vary in their protocols. Therefore, it is necessary to remain cautious in interpreting the results. In addition, in the event of an anxiodepressive disorder, the practice of yoga does not replace medical and psychological care. These results however suggest that yoga can not only be used as a physical activity, but also to improve mental health.

Yoga also improves mental performance

Practicing yoga also seems to have an effect on cognitive performance. A meta-analysis published in 2020 and covering 13 articles shows that following yoga sessions, adults with or without cognitive impairment showed improvements in their attention performance , memory and inhibition.

These enhancements may be related to cerebral changes observed through brain imaging, particularly increased gray matter volume in the hippocampus, the medial temporal lobe, the prefrontal cortex, the insula and the cingulate cortex, region closely related to cognitive. performance. Furthermore, the increased activity of the frontal regions of the brain is long-lasting. However, the authors of these works recommend conducting more in-depth studies, in larger samples and using standardized protocols (randomised controlled trials), to improve the quantity and quality of data available.

It is important to note that the improvements observed seem to be specifically due to the mindfulness and meditation exercises that accompany the yoga sessions. During the sessions, the use of these exercises can have an important synergetic effect. This may mean that, in order to observe the effects of yoga on anxiety symptoms and cognition, it is necessary to learn how to direct one’s attention to the present moment and his emotions. In addition, other factors such as being in a group during the sessions and having positive interactions may also contribute to the reduction of anxiety-depressive symptoms.

If you want to practice yoga and see for yourself its effects, you have to answer one question: which one to choose? Among the many existing types of yoga, three appear regularly in the studies we reviewed: Hatha yoga, Kundalini yoga or Kripalu yoga. If you had to pick one to start with, this would probably be one of them… Just find a class near you!