Gray Matter Changes in Adolescents Participating in a Meditation Training

Abstract

Meditation has shown to benefit a wide range of conditions and symptoms, but the neural mechanisms underlying the practice remain unclear. Magnetic resonance imaging (MRI) studies have investigated the structural brain changes due to the practice by examining volume, density, or cortical thickness changes. However, these studies have focused on adults; meditation's structural effects on the adolescent brain remain understudied. In this study, we investigated how meditation training affects the structure of the adolescent brain by scanning a group of 38 adolescents (16.48 ± 1.29 years) before and after participating in a 12-week meditation training. Subjects underwent Training for Awareness, Resilience, and Action (TARA), a program that mainly incorporates elements from mindfulness meditation and yoga-based practices. A subset of the adolescents also received an additional control scan 12 weeks before TARA. We conducted voxel-based morphometry (VBM) to assess gray matter volume changes pre-to post-training and during the control period. Subjects showed significant gray matter (GM) volume decreases in the left posterior insula and to a lesser extent in the left thalamus and left putamen after meditation training. There were no significant changes during the control period. Our results support previous findings that meditation affects regions associated with physical and emotional awareness. However, our results are different from previous morphometric studies in which meditation was associated with structural increases. We posit that this discrepancy may be due to the differences between the adolescent brain and the adult brain.

Role of meditation to improve children's health: Time to look at other strategies

“…Another large school‐based RCT of 13–20‐year‐old students reported significant decreases in depression in the intervention group ( n = 201) after weekly mindfulness training of 100 min plus 15 min of daily home practice over 8 weeks, when compared to the control group who had no intervention ( n = 207) 32 . These findings are consistent with a recent cohort study in 38 adolescents aged 16.5 years old that reported improvements in brain structure in those areas of the brain linked to physical and emotional awareness, after a weekly mindfulness program that ran over 12 weeks, when compared to controls who did not participate in the mindfulness meditation program ( n = 21) 33 . In addition, an RCT study in 15 high school girls aged 16–18 years old, who were classified as having dysfunctional eating behaviours, demonstrated that weekly 90‐min sessions of mindfulness‐based stress reduction over 8 weeks improved body image perceptions when compared to controls who did not practice mindfulness ( n = 15) 34 …”

Mindfulness, emotional intelligence and occupational burnout in intensive care nurses: A mediating effect model

“…Consequently, a more skilful approach and a new perspective could be utilizing (Ghawadra et al., 2019; Gu et al., 2020), thereby reducing emotional exhaustion and depersonalization. Meanwhile, studies showed that long‐term mindfulness meditation training could thicken the cerebral cortex responsible for attention and comprehensive emotions, shrink the amygdala related to fear emotions and strengthen the function of the insula (Seminowicz et al., 2020; Yuan et al., 2020), which lead the individuals to be more positive and optimistic. These studies proved that the effect of mindfulness on emotional exhaustion from the perspective of neurophysiological mechanism, and depersonalization is the result of emotional exhaustion.…”

Training-Induced Neural Plasticity in Youth: A Systematic Review of Structural and Functional MRI Studies

“…As discussed above, opposite correlations with performance can be observed in children compared with adults, e.g., in one study, thinning of the cortex was associated with higher intelligence at younger age, however, this relationship was reversed in young adults, where higher IQ correlated positively with increase in cortical thickness (Schnack et al, 2015 ). Similarly, one of the reviewed training studies (Yuan et al, 2020 ) reported that the observed VBM changes with meditation training in the studied sample of adolescents were opposite in directionality compared with the previously published VBM literature in adults with meditation training, which may be due to developmental synaptic pruning effects (Giedd et al, 1999 );…”

“…The normalized clustering coefficient and small-worldness displayed significant group × timepoint interactions, both with large effect sizes: −1.1 and −1.4, respectively. Finally, in the seventh study, an effect size of Cohen's d = 0.47 was reported for gray matter volume decreases in the left posterior insula in adolescents with meditation training (Yuan et al, 2020 ). Interestingly, the authors report that the observed VBM changes with meditation training in the studied sample of adolescents were opposite in directionality compared with the previously published VBM literature in adults with meditation training (Yuan et al, 2020 ).…”