Brain recordings show real but modest shifts while people meditate, and the pattern depends on the kind of meditation. A 2016 meta-analysis of 78 brain-imaging studies found that focused attention, mantra, open monitoring and loving-kindness practices each engaged a distinct set of regions[1]. In EEG recordings of electrical activity, a 2026 meta-analysis found that alpha, beta and gamma activity tended to rise during meditation, but found no reliable change in theta waves[2], the rhythm popular accounts most often tie to meditation. Most of these studies are small, and their results vary widely.
Here is what the research shows about the meditating brain, where it is weaker than the headlines suggest, and a short practice that follows what the studies found.
What happens in the brain during meditation?
Different styles of meditation recruit different brain networks, with only a little overlap. The 2016 meta-analysis pooled 31 experiments with 527 participants. A few areas, including the insula and the dorsal anterior cingulate cortex, were active across several techniques, but the authors wrote that "convergence is the exception rather than the rule"[1]. They found medium effect sizes and also flagged many methodological concerns, so "meditation" is better treated as a family of mental exercises than as one brain state.
Within one style, the brain moves through a cycle. In a 2012 study, 14 meditation practitioners meditated on the breath inside an MRI scanner and pressed a button each time they realized their mind had wandered[3]. During mind wandering, regions of the default mode network were active, a set of areas long linked to a wandering mind. The moment of noticing engaged the salience network, and shifting attention back to the breath and holding it there engaged parts of the executive network. Activity in these phases also varied with how much meditation people had done over their lives. Seen this way, a sitting is less a steady state than a loop that you repeat: wander, notice, return.
Whether any of this lasts beyond the meditation itself is less clear. In the largest controlled study, 218 adults who had never meditated showed no structural brain changes after an 8-week mindfulness course compared with control groups[4]. That debate is covered in our look at whether meditation rewires the brain.
Does meditation increase theta waves?
Sometimes, but not reliably enough to call meditation a theta state. A 2018 systematic review found that focused attention and open monitoring were linked to increases in theta activity at the front of the head, while alpha activity rose toward the back during both, and changes tended to be larger in people with more training[5]. An earlier review described an overall slowing of EEG activity with meditation, with theta and alpha related to proficiency, but called the findings variable[6].
The newest pooled analysis is more cautious. The 2026 meta-analysis found positive pooled effects for alpha, beta and gamma, but no significant pooled effect for theta. It found substantial differences between studies, and much of the evidence compared groups at a single point in time rather than following people as they trained[2].
Theta also does not simply mean "deeper". In a 2021 study of 13 long-term meditators, who averaged 32 years of practice, and 15 people who had never meditated, theta amplitude was higher when participants reported hindrances, such as drowsiness and distraction, and lower as they reported deeper meditation. Alpha showed the opposite pattern[7]. One idea, put forward in a 2019 perspective paper, is that frontal midline theta reflects the mental control needed to keep a meditation going, and it may play a part in longer-term brain change. The evidence for that second step comes partly from animal studies[8].
Is meditation the same as being half asleep?
No, though beginners often drift that way. Buddhist traditions describe meditation as relaxed alertness that must guard against both restlessness and drowsiness, and a 2014 review found that early, effortful stages of practice may bring more fatigue and sleepiness, while later stages tend toward greater wakefulness[9]. The drowsiness in the 2021 study above counted as a hindrance, not as depth[7]. The edge of real sleep is a different state with its own research, covered in our piece on sleep onset and creativity.
What does yoga nidra do to the brain?
Yoga nidra, a guided deep-relaxation practice usually done lying down, has some intriguing brain findings and many weak trials. In a small 2002 brain-scan study, a tracer that competes with dopamine bound 7.9% less in the ventral striatum during yoga nidra than while people listened to speech with their eyes closed. The authors estimated this as a 65% increase in dopamine release, and the change tracked a rise in EEG theta[10]. Participants reported less desire to act and more vivid imagery. It was a single small study, and the 65% figure is derived from the tracer change rather than measured directly.
The symptom trials are larger but uneven. In a 2025 randomized trial of 362 adults, an 11-minute online yoga nidra practiced over two months produced small improvements in well-being measures compared with a waiting list, with effect sizes between 0.08 and 0.16[11]. A 2026 meta-analysis of 73 studies with 5,201 participants found larger benefits for stress, anxiety and depression, but cautioned that, given low study quality, those estimates likely overstate the effect[12].
| Style | What you do | What brain studies found | How strong |
|---|---|---|---|
| Focused attention | Rest attention on one thing, such as the breath, and return when it wanders | Default mode network during wandering, salience network on noticing, executive network on returning[3]; more frontal theta and posterior alpha[5] | Several small studies |
| Open monitoring | Notice whatever arises without settling on one object | Its own activation pattern[1]; more frontal theta and posterior alpha[5] | Small studies |
| Loving-kindness | Silently wish yourself and others well | Its own activation pattern[1] | Few studies |
| Yoga nidra | Lie down and follow a guided tour of the body and breath | Dopamine release and more theta in one PET study[10] | One small imaging study |
How do you practice focused-attention meditation?
Sit upright, rest your attention on your breath, and treat each return from a wandering thought as the exercise itself. These steps follow the wander, notice, return cycle from the scanner study[3].
- Sit in a chair with your back upright and your feet on the floor, and set a timer for 10 minutes. An upright posture is a common way to stay on the alert side of relaxed.
- Close your eyes or let your gaze rest on the floor a little ahead of you.
- Find the place where you feel your breath most clearly, such as the nostrils, chest or belly, and rest your attention there.
- When you realize your mind has wandered, pause for a moment to notice where it went. That noticing is the step the salience network handled in the scanner.
- Bring your attention back to the breath without scolding yourself. If it happens fifty times, you have done fifty repetitions.
- If you start to feel heavy or foggy, open your eyes, sit up straighter, or take a few deeper breaths. If you feel restless, lengthen your exhale.
- When the timer sounds, note in a word or two whether you felt mostly drowsy, mostly restless or mostly settled. Over a few weeks the notes will show you which way you tend to drift.
If silence makes this hard, a guided recording can carry you through the first few weeks. Whitespace is a self-guided meditation app that speaks: you bring the intention, and it writes and voices a meditation for exactly that.
Why are brain studies of meditation so mixed?
Mostly because the studies are small and their methods differ. A 2018 critique by 15 researchers in the field warned that poor methods and misinformation about mindfulness could leave the public "harmed, misled, and disappointed", and gave particular attention to brain imaging[13]. Many EEG studies compare long-time meditators with non-meditators at one point in time, which cannot show that meditation caused the difference[2]. Read single brain-scan findings, including the ones above, as clues rather than proof. Meditation is also not free of side effects: a 2020 review of 83 studies found adverse events, most often anxiety and depression, in 8.3% of participants overall[14].
Questions people ask
What brain waves does meditation produce?
Alpha activity has the most consistent support. A 2026 meta-analysis found pooled increases in alpha, beta and gamma during meditation, but no reliable increase in theta, and results varied a lot between studies.
Is meditation the same as sleep?
No. Traditions describe meditation as relaxed alertness, and in one EEG study drowsiness counted as a hindrance to deeper meditation. Beginners do often feel sleepy, which tends to ease with practice.
What is the default mode network?
It is a set of brain regions that tends to be active when the mind wanders. In a scanner study of breath meditation, it was active during mind wandering, and other networks took over when people noticed and returned to the breath.
How long does it take for meditation to change the brain?
Activity shifts within a single sitting. Lasting structural change is less certain: the largest controlled study, in 218 adults, found no structural brain changes after an 8-week mindfulness course compared with control groups.
Can meditation have side effects?
Yes, for some people. A 2020 review of 83 studies with 6,703 participants found adverse events in 8.3% of people overall, most often anxiety and depression, sometimes in people with no history of mental health problems. If meditating leaves you worse, shorten it, keep your eyes open, and talk to a professional if it persists.