Larger whole brain grey matter associated with long-term Sahaja Yoga Meditation: A detailed area by area comparison

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Sergio Elías Hernández, Roberto Dorta,José Suero, Alfonso Barros-Loscertales,José Luis González-Mora, Katya Rubia

Objectives

Our previous study showed that long-term practitioners of Sahaja Yoga Meditation (SYM) had around 7% larger grey matter volume (GMV) in the whole brain compared with healthy controls; however, when testing individual regions, only 5 small brain areas were statistically different between groups. Under the hypothesis that those results were statistically conservative, with the same dataset, we investigated in more detail the regional differences in GMV associated with the practice of SYM, with a different statistical approach.

Design

Twenty-three experienced practitioners of SYM and 23 healthy non-meditators matched on age, sex and education level, were scanned using structural magnetic resonance imaging (MRI). Their GMV were extracted and compared using Voxel-Based Morphometry (VBM). Using a novel ad-hoc general linear model, statistical comparisons were made to observe if the GMV differences between meditators and controls were statistically significant.

Results

In the 16 lobe area subdivisions, GMV was statistically significantly different in 4 out of 16 areas: in right hemispheric temporal and frontal lobes, left frontal lobe and brainstem. In the 116 AAL area subdivisions, GMV difference was statistically significant in 11 areas. The GMV differences were statistically more significant in right hemispheric brain areas.

Conclusions

The study shows that long-term practice of SYM is associated with larger GMV overall, and with significant differences mainly in temporal and frontal areas of the right hemisphere and the brainstem. These neuroplastic changes may reflect emotional and attentional control mechanisms developed with SYM. On the other hand, our statistical ad-hoc method shows that there were more brain areas with statistical significance compared to the traditional methodology which we think is susceptible to conservative Type II errors.

Citation: Hernández SE, Dorta R, Suero J, Barros-Loscertales A, González-Mora JL, Rubia K (2020) Larger whole brain grey matter associated with long-term Sahaja Yoga Meditation: A detailed area by area comparison. PLoS ONE 15(12): e0237552. doi:10.1371/journal.pone.0237552

Editor: Niels Bergsland, University at Buffalo, UNITED STATES

Monitoring the Neural Activity of the State of Mental Silence While Practicing Sahaja Yoga Meditation

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Sergio E Hernández 1 , José Suero, Katya Rubia, José L González-Mora
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PMID: 25671603 DOI: 10.1089/acm.2013.0450

Abstract

Objective: To identify the neural correlates of the state of mental silence as experienced through Sahaja yoga meditation.

Design: Nineteen experienced meditators underwent functional magnetic resonance imaging during three short consecutive meditation periods, contrasted with a control relaxation condition.

Results: Relative to baseline, at the beginning of the meditation sessions there was a significant increase of activation in bilateral inferior frontal and temporal regions. Activation became progressively more reduced with deeper meditation stages and in the last meditation session it became localized to the right inferior frontal cortex/ right insula and right middle/superior temporal cortex. Furthermore, right inferior frontal activation was directly associated with the subjective depth of the mental silence experience.

Conclusions: Meditators appear to pass through an initial intense neural self-control process necessary to silence their mind. After this they experience relatively reduced brain activation concomitant with the deepening of the state of mental silence over right inferior frontal cortex, probably reflecting an effortless process of attentional contemplation associated with this state.

Source: National Library of Medicine, National Center for Biotechnology Information, https://pubmed.ncbi.nlm.nih.gov/25671603/

Short-term Sahaja Yoga Meditation Training Modulates Brain Structure and Spontaneous Activity in the Executive Control Network

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Alessandra Dodich 1 2 , Maurizio Zollo 3 , Chiara Crespi 1 4 , Stefano F Cappa 4 5 , Daniella Laureiro Martinez 6 , Andrea Falini 1 7 , Nicola Canessa 4 8
Affiliations expand
PMID: 30485713 PMCID: PMC6346416 DOI: 10.1002/brb3.1159
Free PMC article
Abstract

Introduction: While cross-sectional studies have shown neural changes in long-term meditators, they might be confounded by self-selection and potential baseline differences between meditators and non meditators. Prospective longitudinal studies of the effects of meditation in naïve subjects are more conclusive with respect to causal inferences, but related evidence is so far limited.

Methods: Here, we assessed the effects of a 4-week Sahaja Yoga meditation training on gray matter density and spontaneous resting-state brain activity in a group of 12 meditation-naïve healthy adults.

Results: Compared with 30 control subjects, the participants to meditation training showed increased gray matter density and changes in the coherence of intrinsic brain activity in two adjacent regions of the right inferior frontal gyrus encompassing the anterior component of the executive control network. Both these measures correlated with self-reported well-being scores in the meditation group.

Conclusions: The significant impact of a brief meditation training on brain regions associated with attention, self-control, and self-awareness may reflect the engagement of cognitive control skills in searching for a state of mental silence, a distinctive feature of Sahaja Yoga meditation. The manifold implications of these findings involve both managerial and rehabilitative settings concerned with well-being and emotional state in normal and pathological conditions.

(a) Spatial contiguity between the right inferior frontal clusters showing increased GM density (in blue) and a modulation of coherent activity (in red) after meditation training. The overlap between morphometric and resting‐state data is shown in green. (b) Spectral power of intrinsic activity in the executive control network, providing a measure of the contribution of each frequency bin (between 0 and 0.25 Hz) to the fluctuations of BOLD signal at rest (asterisks indicate the frequency bins displaying a significant effect in time‐by‐group interaction). Meditators, compared with non meditators, display a reduction of power at ultra‐low frequencies, and an increase at low–middle frequencies, after training. (c) Average GM density in the cluster resulting from VBM interaction analysis for the two time points of both training (MG) and control (CG) groups (error bars depict standard deviations). Meditators, compared with non meditators, display a significant increase of GM density with training in the right fronto‐insular cluster depicted in green color in panel A

References

  • Adan A., Serra‐Grabulosa J. M., Caci H., & Natale V. (2009). A reduced Temperament and Character Inventory (TCI‐56). Psychometric properties in a non‐clinical sample. Personality and Individual . Differences, 46(7), 687–692. 10.1016/j.paid.2009.01.023 – DOI
  • Aftanas L. I., & Golocheikine S. A. (2001). Human anterior and frontal midline theta and lower alpha reflect emotionally positive state and internalized attention: High‐resolution EEG investigation of meditation. Neuroscience Letters, 310(1), 57–60. 10.1016/S0304-3940(01)02094-8 – DOI – PubMed
  • Aftanas L. I., & Golocheikine S. A. (2002). Non‐linear dynamic complexity of the human EEG during meditation. Neuroscience Letters, 330(2), 143–146. 10.1016/S0304-3940(02)00745-0 – DOI – PubMed
  • Aftanas L. I., & Golosheikin S. A. (2003). Changes in cortical activity during altered state of consciousness: Study of meditation by high resolution EEG. Fiziologiia Cheloveka, 29(2), 18–27. – PubMed
  • Allen E. A., Erhardt E. B., Damaraju E., Gruner W., Segall J. M., Silva R. F., & …Calhoun, V. D. (2011). A baseline for the multivariate comparison of resting‐state networks. Frontiers in Systems Neuroscience, 5, 2 10.3389/fnsys.2011.00002 – DOI – PMC – PubMed

Source: National Library of Medicine, National Center of Biotechnology Information, https://pubmed.ncbi.nlm.nih.gov/30485713/