Mantra meditation training over a two-week period of Kundalini yoga/meditation reduced activity in key default mode network (DMN) regions—the pregenual anterior cingulate cortex and precuneus—with trends toward decreased activation in the posterior cingulate cortex. These reductions occurred even when compared to a finger-tapping control task that itself deactivates DMN regions, indicating that mantra practice suppresses DMN activity beyond the control task. The choice of control task matters: prior studies using language-based controls may have masked these effects. The findings suggest that mantra meditation, like focused attention and open monitoring practices, modulates DMN activity.
Moderately experienced meditators with less than two years of practice show significant activation in the hippocampus and parahippocampal formations during silent mantra meditation, as measured by functional magnetic resonance imaging. Activation also occurred in the middle cingulate cortex and precentral cortex, but not in the anterior cingulate cortex, and only small clusters appeared in the prefrontal cortex. The findings suggest that hippocampal activation occurs early in meditation practice and across different meditation styles, including relaxation. The authors propose further research to clarify whether this hippocampal activity relates to memory consolidation.