Mind wandering during breath focus meditation is linked to specific changes in brain waves. In 25 novice meditators, episodes of mind wandering showed increased amplitude and decreased frequency of theta oscillations (4-8 Hz), while alpha oscillations (8-14 Hz) decreased in amplitude and increased in frequency. Mind wandering also involved greater harmonicity and phase synchrony between theta and alpha rhythms. These spectral changes resemble those seen in controlled cognitive processes like memory and executive control, suggesting shared neurocognitive mechanisms. The findings indicate that theta-alpha oscillatory activity could serve as a basis for EEG-neurofeedback protocols to detect mind wandering during meditation.
Experienced meditators report greater focus and less mind wandering during meditation than non-meditators, and these differences are reflected in their brain activity. In a study of 29 experienced meditators and 29 non-meditators, EEG recordings during rest and breath-focus meditations showed that meditators, but not controls, had a significant decrease in individual alpha frequency and amplitude and a steeper 1/f slope during meditation compared to rest. Controls, but not meditators, showed increased alpha amplitude during mind wandering relative to breath focus. The findings indicate that meditation training alters both the subjective experience and the oscillatory and non-oscillatory components of brain activity.