Mindfulness meditation alters alpha amplitude without affecting arousal

Mindfulness meditation has experienced a surge in popularity due to its well-documented health benefits, although the mechanisms driving these benefits are not clearly understood. This study explored whether mindfulness of breathing meditation induces changes in brain function and physiological responses related to attention or arousal mechanisms. Electroencephalography (EEG) and skin conductance level (SCL) data were recorded during eyes-closed resting and meditation states in 42 young adults (M_age = 21.05 years; 26 females) across two sessions (pre-training, post-training) six weeks apart. Between sessions, participants were randomly assigned to one of two groups completing a daily 15-min activity involving either mindfulness (n = 21) or music (n = 21; active-control group). Results revealed a significant reduction in alpha amplitude (8-13 Hz) during meditation compared to rest. Additionally, post-training, there was a smaller alpha reduction during meditation in the mindfulness group, particularly in the frontal/posterior region, evidence of a possible trait effect. While SCL remained stable over meditation and rest, a decrease was evident in both groups post-training, indicating reduced arousal. However, no significant associations were found between SCL and global alpha amplitude. Together, these findings suggest mindfulness meditation reduces alpha band activity, likely reflecting enhanced attentional engagement rather than an arousal change, supporting the view of mindfulness meditation as a state of relaxed alertness. The present findings provide new insights into the mechanisms underlying mindfulness meditation, emphasising the importance of alpha band activity in attentional control, which may contribute to its health benefits, including improved emotional regulation and cognitive functioning.