Brainwaves and meditation
When meditation is mentioned, many people think of something mystical. Something beyond science. But over the past few decades, brain research has begun to look more closely – and some of what it has found is genuinely remarkable.
This text is a revised version. I originally wrote things here that I believed were established facts, but are not. What remains is now accompanied by a source – and what I had to remove is mentioned too. I prefer that to telling a beautiful story.
Brainwaves – frequencies, not levels of consciousness
Our brain constantly produces electrical activity. This can be measured as waves, and different frequency ranges predominate depending on the state. So far, this is uncontroversial.
What follows from it is less uncontroversial. The popular account – that each frequency is a rung on a ladder of consciousness and meditation takes you down that ladder – does not stand up to the research evidence.
Alpha waves (8–12 Hz) represent relaxed alertness. You are awake but at ease. This is the best-supported finding and fits well with what many people experience at the beginning of a session.
Theta waves (4–8 Hz) lie in the transitional range between waking and sleeping and also increase measurably during meditation. They are often associated with deep insights – I used to write here that they “stimulate healing processes”. There is no evidence for that, and the sentence has gone.
Gamma waves (from about 30 Hz) feature in one spectacular study: in 2004, Lutz and colleagues measured unusually high gamma amplitudes and synchrony during compassion meditation in Tibetan monks with many thousands of hours of practice. This is a real finding – but one involving very few, extremely experienced practitioners doing a particular practice, not a universal law of meditation.
Delta waves (below 4 Hz) dominate during deep sleep. Whether they play a distinct role in deep meditation remains open – the review found no clear pattern here. So I leave this as what it is: unclear.
What I had to remove: the left and right hemispheres
There used to be a whole section here claiming that the left hemisphere was responsible for logic and language, the right for intuition and creativity, that the left dominated in everyday life and meditation brought the two into balance. I even added: “This is not an esoteric concept – it is neurology.”
That was wrong – the opposite was true.
I am deliberately leaving this section as a correction rather than quietly deleting it. The hemisphere story is so widespread in meditation and coaching circles that it is more useful to explicitly put it to rest.
What happens instead
Because the experience this is really about is real. Anyone who meditates knows the moment when analysing stops and something else takes over: you no longer think about yourself; you experience yourself. Logic and feeling no longer get in each other’s way.
There is a better description of precisely this shift than left and right.
This captures it much better than two halves of the brain: it is not about one side becoming quieter and the other louder, but about which mode we are perceiving in at that moment. And about the fact that the second mode can be practised.
What changes with practice
With regular practice, many practitioners report being able to stay longer in a state that is both calm and alert. This is consistent with the alpha-theta finding.
Whether stable patterns also develop that do not occur in non-meditators is much harder to demonstrate than it often sounds: the studies involve small groups, very different forms of meditation and people who have voluntarily chosen years of practice. This makes cause and effect difficult to separate.
Technical aids
There are audio products that work with frequencies – binaural beats and similar approaches. They can be pleasant and make it easier to begin when the mind is restless.
Technology can open a door. You have to walk through it yourself.
What measurement can do – and what it cannot
An EEG shows that something changes during meditation. It does not show that the experience behind it is what we believe it to be, and it does not validate any tradition.
The more honest statement is therefore: research finds correlates. It measures what accompanies meditation. It does not decide what the experience means.
And the experience itself does not need an EEG anyway. It only needs you, a quiet place and the willingness to become still.
The beginning is always the same
Whether alpha or theta – in the end, it comes down to the same thing: sit down. Become still. Observe.
Science gives us a language for a small part of what happens. Experience gives us the rest.