Meditation attenuates default-mode activity: A pilot study using ultra-high field 7 Tesla MRI.

Using 7 Tesla functional MRI, a pilot study scanned 10 beginner meditators during focused attention meditation (attending to breathing) and non-focused rest. After adjusting for physiological differences, meditation reduced activity in default-mode network hubs (antero-medial prefrontal and posterior cingulate cortices, precuneus) and visual and thalamic regions compared to rest. These reductions survived stringent corrections for physiological fluctuations. State mindfulness scores rose significantly after the session and remained elevated at a 2-week follow-up. The findings support evidence that focused attention meditation dampens default-mode activity tied to self-referential processing and demonstrate the feasibility of ultra-high field fMRI for meditation research.

Study at a glance

Abstract

Mapping the neurobiology of meditation has been bolstered by functional MRI (fMRI) research, with advancements in ultra-high field 7 Tesla fMRI further enhancing signal quality and neuroanatomical resolution. Here, we utilize 7 Tesla fMRI to examine the neural substrates of meditation and replicate existing widespread findings, after accounting for relevant physiological confounds. In this feasibility study, we scanned 10 beginner meditators (N = 10) while they either attended to breathing (focused attention meditation) or engaged in restful thinking (non-focused rest). We also measured and adjusted the fMRI signal for key physiological differences between meditation and rest. Finally, we explored changes in state mindfulness, state anxiety and focused attention attributes for up to 2 weeks following the single fMRI meditation session. Group-level task fMRI analyses revealed significant reductions in activity during meditation relative to rest in default-mode network hubs, i.e., antero-medial prefrontal and posterior cingulate cortices, precuneus, as well as visual and thalamic regions. These findings survived stringent statistical corrections for fluctuations in physiological responses which demonstrated significant differences (p < 0.05/n, Bonferroni controlled) between meditation and rest. Compared to baseline, State Mindfulness Scale (SMS) scores were significantly elevated (F(3,9) = 8.16, p < 0.05/n, Bonferroni controlled) following the fMRI meditation session, and were closely maintained at 2-week follow up. This pilot study establishes the feasibility and utility of investigating focused attention meditation using ultra-high field (7 Tesla) fMRI, by supporting widespread evidence that focused attention meditation attenuates default-mode activity responsible for self-referential processing. Future functional neuroimaging studies of meditation should control for physiological confounds and include behavioural assessments.