Mindfulness meditation practitioners show lower frontal gamma brain activity, indicating reduced default mode network (DMN) engagement and less self-referential thinking, both as a lasting trait and during a time production task. They also produce longer time estimates, which correlate with lower frontal gamma. Additionally, they exhibit increased posterior gamma power, suggesting heightened attention and sensory awareness. These effects appear regardless of meditation proficiency, suggesting neuroplastic changes in self-referential and attentional networks from early practice stages. The findings demonstrate that EEG can non-invasively measure DMN activity.
Choosing the reference electrode for EEG recordings substantially affects measures of brain activity, including the default mode network (DMN). Simulated data showed that the infinity reference obtained by the reference electrode standardisation technique (REST) exactly recovered the true network configuration. In real EEG data from 15 participants, different references—REST, average reference, linked mastoids, and left mastoid—produced significant differences in power spectra, coherence, and DMN connectivity. Compared with REST, the average reference strengthened long-distance connections between anterior and posterior brain areas, while linked mastoids and left mastoid references disrupted posterior connectivity. The effects depended on EEG frequency band. REST is a valid reference technique for objective comparisons across studies and clinical practice.