What Meditation Does to the Brain

Meditation changes how several brain networks behave, and a few months of practice may change some structure as well. The best-supported finding concerns the network that hums along when the mind drifts into thoughts about yourself. In experienced meditators its two main hubs, in the medial prefrontal cortex and the posterior cingulate, were relatively quiet whichever style they practised, and they stayed more tightly linked to regions that monitor and steer attention, at rest as well as during meditation (Brewer et al., 2011).

The step past that is the useful part. Those findings describe the small movements of an ordinary sit: drifting off, noticing, coming back, feeling the body instead of narrating it. Once you know which movement the research keeps pointing at, you can practise it on purpose. The science is also younger and shakier than the headlines suggest, and the last part of this page is about that.

What the brain is doing during a sit

Every breath practice runs the same small cycle. You rest attention on the breath, the mind slides off into a plan or a memory, at some point you notice, and you bring it back. Sharon Salzberg expected hundreds of breaths before her mind wandered the first time she tried. It was, in her words, “one breath, and I’d be gone”.

attention on breathmind drifts offyou noticeyou come back

Each station maps loosely onto what the scans measure. The drifting belongs to the default mode network, the midline regions that are active during mind-wandering and thoughts about the self. Brewer and colleagues (2011) point out that this kind of wandering goes along with unhappiness, which is a sobering thing to learn about the brain’s resting habit. The noticing and the return lean on control regions, the dorsal anterior cingulate and the dorsolateral prefrontal cortex. In meditators those were more strongly coupled to the posterior cingulate, as if a watchman had been posted near the place where drifting starts. That picture is an interpretation. The study measured connectivity, and the authors call what they found possible mechanisms, consistent with less mind-wandering.

The second movement is quieter. Farb and colleagues (2007) asked people to attend to themselves in two ways. In a narrative focus they thought about what kind of person they are; in an experiential focus they stayed with sensation as it happened. Shifting into experience lowered activity in the medial prefrontal cortex even in newcomers. After an eight-week mindfulness course the drop was larger and more widespread, and a right-side network came in more strongly, including the insula, which carries signals from inside the body. In newcomers the insula and the medial prefrontal cortex were tightly coupled. In the trained group that link had come undone.

The authors read this as two kinds of self-awareness, the self stretched across time and the self in this moment, which normally run together and can be pulled apart with attention training. For a practitioner that is a plain instruction. When you catch yourself in a story about who you are, the way out runs through the body.

A practice built on those two movements

This is a ten-minute sit arranged around the two things the research keeps returning to: catching the drift, and moving from story into sensation.

1. Sit on a chair, a cushion or a bench, whichever you can hold for ten minutes without shifting. A chair is fine, and it is the better choice if your back hurts or getting up from the floor is hard. Feel the weight of your body settle onto the seat.
2. Put your attention on the breath in one place, the belly or the nostrils. Treat it as sensation: the slight coolness of air on the way in, the belly lifting under your clothes.
3. When you find you have drifted, stay with the moment of noticing for one breath before you go back. That small catch is the movement the control-network findings keep circling.
4. If the drift was a story about yourself (how the day went, what someone thinks of you, what you should have said), find one physical sensation that is happening now, the feet on the floor or the hands in your lap, and rest there before returning to the breath.
5. For the last few minutes, widen the field. Let sounds and sensations from the whole body in alongside the breath, without picking any of them up.
6. Before you stand, notice how the body feels and what the mind is doing. Then get up slowly.

Come back each time without scolding yourself. The wandering is the material you are working with.

How much practice the studies used

The structural findings come from programmes measured in weeks. Mindfulness-Based Stress Reduction, the course behind many of these studies, was built by Jon Kabat-Zinn in the late 1970s at the medical school of the University of Massachusetts. It runs for eight weeks and combines meditation, body awareness and yoga.

Shorter doses show up in attention research. The neuroscientist Amishi Jha found that 12 minutes of meditation, five days a week, can protect and strengthen the ability to pay attention, and Richard Davidson has quoted research suggesting benefits from as little as 8 minutes a day. Psychology Today’s overview reports that even 10 minutes raises alpha waves, which are linked to relaxation. Traditions vary: Transcendental Meditation asks for 20 minutes twice a day. Across these sources the steady advice is that showing up daily counts for more than the length of any single sit.

What changes in structure

The best-known structural study is small. Hölzel and colleagues (2011) scanned 16 healthy people with no meditation background before and after an eight-week MBSR course, and compared them with a waiting-list group of 17.

16

Grey matter concentration rose in the left hippocampus, which the team had targeted in advance, and in a whole-brain search it also rose in the posterior cingulate, the temporo-parietal junction and the cerebellum. These regions are involved in learning and memory, emotion regulation, thinking about oneself and taking another person’s perspective. The posterior cingulate is one of the same default mode hubs that Brewer’s meditators quieted, so the activity findings and the structural ones point at overlapping ground.

Cleveland Clinic summarises the wider picture: people who meditate regularly tend to show denser tissue or larger areas in regions that handle the senses, focus and emotion. Treat that as a direction of travel. Reviews of the field judge most structural studies to have weak methods.

Stress, emotion and the body

Vago and Silbersweig (2012) proposed a framework, called S-ART, for how these pieces fit. In their model, mindfulness trains three capacities: seeing what your own mind is doing, adjusting your behaviour in response, and relating to others beyond self-focused needs. A fronto-parietal control network ties these together, and the result they describe is less bias in how we process ourselves.

self-awarenessself-regulationself-transcendence

less self-bias

The authors offer S-ART as a model to guide future research, so it explains more than it proves. It still helps make sense of the scans above: the watchman in Brewer’s study and the loosened self-story in Farb’s both look like self-awareness and self-regulation at work.

The body has its own route into this. The vagus nerve is the main branch of the parasympathetic nervous system and carries information about the inner organs up to the brain. Vagal tone tracks how well a person regulates stress, and breathing can shift it, so Breit and colleagues (2018) suggest that meditation and yoga, by raising it, likely contribute to resilience against mood and anxiety symptoms. The word “likely” is theirs, and it is the right word. Cleveland Clinic points at the stress system as well: the HPA axis, the body’s main stress response, connects to a circuit through the amygdala, hippocampus and prefrontal cortex, and meditation’s benefits may come partly through changes there.

Why a wandering mind matters for the body becomes clearer in Slavich and Irwin’s (2014) work on depression. Their theory holds that social threats, including imagined and symbolic ones, can switch on the immune system’s inflammatory response, and that this response helps drive depressive symptoms. A mind rehearsing an argument at three in the morning is producing that kind of imagined threat. Whether meditation turns the response down is a question this research does not settle.

On attention, the findings are mixed but mostly encouraging. Mindfulness has been shown to increase alpha power, and several studies report a smaller Stroop effect, the slowdown you get when a colour word is printed in a clashing colour, though that result does not always replicate. On pain, Ong and colleagues (2019) list meditation among the approaches that work through the prefrontal cortex, and note that grey matter lost there during chronic pain often returns after successful treatment. Reviews still find too few studies to draw conclusions about meditation and chronic pain.

What the outcomes show

The brain findings would matter less if people did not feel any different. They do, on average. Keng and colleagues (2011) reviewed the empirical work and concluded that mindfulness raises well-being, reduces symptoms and emotional reactivity, and improves self-regulation of behaviour. Hofmann and colleagues (2010) pooled 39 studies with 1,140 participants and found moderate improvements in anxiety and mood, with larger effects in people diagnosed with anxiety and mood disorders, and those gains held at follow-up.

The wider evidence base is now large. One overview gathered 44 meta-analyses covering 336 randomised controlled trials and more than 30,000 participants, and judged that mindfulness programmes have broad potential while naming ways the evidence still needs strengthening.

What the scans cannot tell you yet

Early meditation research, going back to the 1950s, was full of flawed studies. Today’s work uses randomised trials and active control groups more often, but several problems remain.

• Small samples. The grey matter study that is quoted everywhere had 16 people in its training group. Findings this size need repeating before anyone builds on them.
• Before or after. Brewer compared experienced meditators with people who had never meditated. A difference between two groups does not show that meditation caused it; people who stick with meditation for years may have differed from the start.
• Publication bias. Funnel-plot analyses point to publication bias in meditation imaging research, which makes the published picture look better than the full one.
• Different styles, different brains. A review of functional imaging studies found that different meditation styles produce different brain activity, so any one sentence about what meditation does to the brain is a simplification.
• Other causes of the same differences. Teicher and Samson (2016) show that childhood abuse and neglect alter the anterior cingulate, the dorsolateral prefrontal cortex and the hippocampus, many of the same regions meditation studies report on, and that maltreatment has gone unaccounted for in almost all psychiatric imaging studies. A brain scan carries a whole life in it.
• Measuring mindfulness. Self-reported mindfulness has also risen in some control groups, which makes questionnaires a shaky yardstick. Objective measures, such as attention tasks, blood pressure and brain function, are where the stronger recent evidence sits.

Mayo Clinic adds a caution of its own: meditation can sometimes make symptoms of certain mental health conditions worse, and some experts think the research still falls short of proof. If you live with a mental health condition, talk to a professional about whether and how to practise, and use meditation alongside treatment, never in place of it.

Where this leaves you

The neuroscience of meditation is early, the studies are small, and the pictures they produce are easy to oversell. What holds up is modest and useful. The network that spins stories about you can be quieted, the part of you that notices can be kept closer to it, and the body offers a way out of the story whenever you find yourself lost in one. You do not need a scanner to work with any of that. You need the next breath, and the moment you notice you have left it.