Preprint · Jan 2026
Examining the Longitudinal Impact of Mind-Body Interventions on Brain Structure: Secondary Analyses of Data from the HealthyAgers trial
By Todorova N, Phansikar M, Gorka AX et al.
Mindfulness-based stress reduction is an 8-week training program designed to teach individuals how to incorporate mindfulness into their lives to promote stress reduction and well-being (Kabat-Zinn, 1982). Early research exploring the impact of mindfulness-based stress reduction (MBSR) on brain structure reported volumetric increases in regions such as the amygdala, hippocampus, insula, and more (Holzel et al., 2010, 2011; Pickut et al., 2013; Santarnecchi et al., 2014). Findings showing that MBSR can increase brain volume, density, and/or cortical thickness in certain brain regions were largely replicated until recent years, in participant populations ranging from healthy adults of all ages (Fox et al., 2014; Gotink et al., 2016) to clinical populations such as Parkinson’s patients (Pickut et al., 2013) and individuals with opioid dependence (Fahmy et al., 2019). While promising, the majority of the aforementioned studies were conducted on small sample sizes, and regions of significance varied broadly. In more recent years, researchers have aimed to replicate these early findings with methodologically rigorous trials. One such trial found no evidence that MBSR produces structural changes compared to an active control group or a waitlist condition (Kral et al., 2022). Notably, their findings showed that in order to exhibit significant changes in the gray matter volume (GMV) of the amygdala, participants needed to practice mindfulness for a minimum of 22 minutes per day, suggesting a dose-response relationship warranting further exploration. Rigorous studies investigating MBSR for older adults are rare, with one large-scale randomized control trial finding no group differences in hippocampal volume or cortical thickness of the dorsolateral prefrontal cortex (DLPFC) immediately following MBSR intervention, nor at 6-month follow-up (Lenze, 2022). Curiously, they found a significant reduction in hippocampal volume for the MBSR groups as compared to the non-MBSR groups at 18-month follow-up. These null and unexpected findings illustrate a need for further investigation. Our team conducted a randomized control trial comparing an 8-week MBSR intervention to Lifestyle Education (LifeEd), a well-matched active control group. The study protocol has been published by Prakash et al. (2022). Study participants underwent structural and functional MRI imaging at baseline, post-intervention, and at 12-month follow-up. With a sample size of 110 healthy older adults between the ages of 65 and 85, we will explore the impact of both mind-body interventions on older adults’ hippocampal GMV, as well as on the cortical thickness of the DLPFC and insula. We will investigate whether there is a dose-response relationship between engagement with mind-body interventions and changes in cortical thickness and subcortical volume.