Enhanced amygdala-anterior cingulate white matter structural connectivity in Sahaja Yoga Meditators

PLoS One. 2024 Mar 28;19(3):e0301283. doi: 10.1371/journal.pone.0301283. eCollection 2024.

Abstract

Objective: To study the white matter connections between anterior cingulate cortex, anterior insula and amygdala as key regions of the frontal-limbic network that have been related to meditation.

Design: Twenty experienced practitioners of Sahaja Yoga Meditation and twenty nonmeditators matched on age, gender and education level, were scanned using Diffusion Weighted Imaging, using a 3T scanner, and their white matter connectivity was compared using diffusion tensor imaging analyses.

Results: There were five white matter fiber paths in which meditators showed a larger number of tracts, two of them connecting the same area in both hemispheres: the left and right amygdalae and the left and right anterior insula; and the other three connecting left anterior cingulate with the right anterior insula, the right amygdala and the left amygdala. On the other hand, non-meditators showed larger number of tracts in two paths connecting the left anterior insula with the left amygdala, and the left anterior insula with the left anterior cingulate.

Conclusions: The study shows that long-term practice of Sahaja Yoga Meditation is associated with larger white matter tracts strengthening interhemispheric connections between limbic regions and connections between cingulo-amygdalar and cingulo-insular brain regions related to top-down attentional and emotional processes as well as between top-down control functions that could potentially be related to the witness state perceived through the state of mental silence promoted with this meditation. On the other hand, reduced connectivity strength in left anterior insula in the meditation group could be associated to reduced emotional processing affecting top-down processes.

MeSH terms

  • Amygdala / diagnostic imaging
  • Brain
  • Diffusion Tensor Imaging
  • Gyrus Cinguli / diagnostic imaging
  • Humans
  • Magnetic Resonance Imaging / methods
  • Meditation* / psychology
  • White Matter* / diagnostic imaging
  • Yoga* / psychology

Grants and funding

KR is supported by Efficacy and Mechanism Evaluation (EME) programmes, an MRC and NIHR partnership (project ref: NIHR130077 and NIHR203684) and by the NIHR Maudsley Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King’s College London. The views expressed are those of the authors and not necessarily those of the National Health Service, the NIHR or the Department of Health and Social Care. ABL has received research support from the Universitat Jaume I (UJI-B2020-30; UJI-B2016-21). The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.