Mindfulness meditation acutely increases frontal theta brain activity during practice, but long-term practitioners show lower trait frontal theta activity compared to short-term practitioners. This lower baseline activity may reflect expert meditators' ability to limit unnecessary information processing and enhance awareness of present experience. The acute theta increases during meditation appear related to concentration rather than mindfulness specifically. Twenty participants were studied, including ten experienced Buddhist meditators.
Long-term Soto Zen Buddhist meditators showed no significant change in beta brainwave activity during an adapted meditation task, contrary to expectations. Instead, the frequency of weekly meditation practice correlated with increased induced theta power and a higher theta/beta ratio, suggesting that mindfulness meditation involves permitting distractions and deliberately reducing attention rather than actively focusing.