Neural mechanisms underlying the depression-reducing effects of mindfulness-based stress reduction in university students: A Rs-fMRI study

Depression constitutes a major global public health burden, with university students exhibiting a disproportionately high prevalence of depressive symptoms. Although Mindfulness-Based Stress Reduction (MBSR) has demonstrated efficacy in alleviating depressive symptomatology, its underlying neurobiological mechanisms remain incompletely understood. This randomized controlled trial investigated neural activity changes and functional connectivity alterations of MBSR's depression-reducing effects in university students using resting-state functional magnetic resonance imaging (rs-fMRI). Forty-two healthy university students were randomly assigned to either an 8-week MBSR intervention or a control group. Clinical outcomes were assessed using the Depression Anxiety Stress Scales-21, and rs-fMRI data were acquired to examine regional brain activity and functional connectivity. Results demonstrated that MBSR participants exhibited greater improvements in depression scores compared to the control group. Neuroimaging analyses indicated that MBSR intervention led to reduced Amplitude of Low-Frequency Fluctuations (ALFF), fractional ALFF, and Regional Homogeneity in the right middle cingulate cortex (MCC). Furthermore, seed-based functional connectivity analysis demonstrated decreased connectivity between the right MCC and regions involved in emotional regulation and self-referential processing, including the left hippocampus and bilateral precuneus, in the MBSR group relative to controls. Furthermore, changes in MCC-hippocampus and MCC-precuneus functional connectivity were negatively correlated with improvements in depression scores. These findings provide novel evidence that MBSR promotes adaptive neural reorganization, characterized by reduced activity and altered functional connectivity within the MCC-centric emotional regulation network, providing mechanistic insight into for its depression-reducing effects in subclinical populations and supporting the neural efficiency hypothesis.