Nowadays, it is rare to meet a person who is not practicing, has not tried, or at least heard of meditation. According to social media and various meditation gurus, it would seem that meditation can solve all of the problems of the modern world: stress, obesity, financial difficulty, insomnia, anxiety and cure various diseases, such as depression or cancer. But at the same time, mindfulness is still considered by many to be a very esoteric practice, associated with shamanism, chakra opening, or some other voodoo pseudoscience practice. Mindfulness is seen as something that is very 'unscientific'.
Meditation practice reliably increases the ability to observe your thoughts, feelings, sensations and impulses as they are happening.
Meditation can promote healthy aging and delay the onset of dementia or cognitive impairment.
A 2015 systematic review showed that meditation affects our brain waves.
But what does science and peer-reviewed research articles say about meditation? This is the first article in a series “Science of Meditation” where I describe the science behind meditation on how it affects our brain, body, behavior and health. In this article we will start at the top and explore what is happening in your brain when you meditate.
Meditation can change the size and activity of your brain
According to a 2014 meta-analysis which reviewed 21 neuroimaging studies examining ∼300 meditation practitioners, meditation practice reliably increases brain volume of eight brain regions that are associated with meta-awareness (the ability to observe your thoughts, feelings, sensations and impulses as they are happening), exteroceptive and interoceptive body awareness, memory, sensory information processing, pain, self-regulation, self-control, attention, emotion regulation, and intra- and interhemispheric communication.
These results are supported by studies examining how meditation affects brain activity. Several meta-analyses show that meditation changes not only the size of these brain parts, but can also activate them. This means that during and after meditation practice, we find increased blood flow to the above listed brain areas due to increased brain volume and increased neuronal cell activity.
Most of the time, but not always, larger parts of the brain, meaning more brain cells and connections between them, means that this part of the brain is used often and a lot, activated more times, indicating better functioning of that part of the brain. Thus, according to these meta-analyses, people who practice mindfulness could have better control over themselves and their emotions, better understanding of their bodies and emotions, and be more empathetic and aware, compared to non-practitioners.
It should also be mentioned that with age and in the case of neurodegenerative diseases, brain cells die, the volume of the brain decreases and functions related to the affected parts of the brain deteriorate, such as memory or coordination of movements. Therefore, we could say that having more brain cells in certain parts of the brain makes us more protected from this age-related or neurodegenerative disease damage.
Interestingly, a number of research studies show that this age-related decline in brain volume is somewhat slower and smaller in people who meditate. The more and the longer people meditate, the greater the protection. Meditation can promote healthy aging and delay the onset of dementia or cognitive impairment.
Other systematic reviews and meta-analyses published throughout 2018-2021, although differ in one brain region or another, also show that meditation activates and increases the size of brain areas related to introspection (body, thoughts, emotions), self-regulation and emotion regulation.
The fact that meditation increases brain volume and activity suggests that meditation-induced effects on the brain are long-lasting and continue even after the practice itself. After all, we want to be "zen" not only during the quiet meditation practice itself, but also after leaving the session, when we sit behind the car wheel, communicate with our family and try to live a calmer and more conscious life.
Meditation can affect your brain waves
How our brains and us change over time through regular meditation practice is beautifully illustrated by research that measures brain waves. Our brain cells communicate with each other by sending electrical signals that we can measure with electrodes on the skull. The signal we will detect is the so-called brain waves, which describe the type of brain cell activity prevailing at that time.
Different brain waves are associated with different states of the brain and of us. For example, slow large brain waves, called delta waves, are found when we sleep; a bit faster alpha waves are detected when we are awake, but relaxed; while fast beta waves are detected when we are fully awake and alert.
A 2015 systematic review showed that meditation affects our brain waves. In particular, meditation is associated with increased alpha waves, which reflect a state of relaxation (perhaps no one was surprised by this finding). This is the most reliable result found by the vast majority of studies.
Interestingly, the more experienced the meditation practitioner is, the more likely we are also to detect theta waves in their brain. Theta waves are associated with concentration, alertness, and focus. Lastly, in highly experienced meditators we also detect gamma waves, which are related to concentration, working memory, conscious and clear perception of the moment, as well as the so-called "flow" state.
When applying one or another practice or intervention, it is useful to know which parts of the brain it affects, in order to understand whether the intervention is effective, how it works and how long the effect lasts.
However, it should not be forgotten that even the repeated movement of the little finger changes the structure and activity of the brain (for example, the part of the cerebral cortex responsible for the movements of the little finger). Anything we do (and especially repeatedly) changes the brain. This is the well-known neuroplasticity of the brain. Thus, structural and functional studies alone are not enough to understand the effects of meditation on our body, they need to be linked to observable changes in our state, behavior and well-being caused by the intervention.
In the following article we will explore how these meditation related changes in the brain translate into our behavior. For example, how changes in our brains' emotional and stress centers affect how we respond to stress and how fast we recover after stressful situations.