Mindfulness Practice and Increases in Gray Matter Density, Gray Matter Volume, and Cortical Thickness: A Scoping Review

Background/Objectives: Mindfulness-based interventions (MBIs) have been linked to psychological and cognitive benefits, yet evidence for their impact on brain structure remains sparse. Neuroimaging suggests MBIs may alter gray matter volume (GMV), density (GMD), and cortical thickness (CT). The purpose of this scoping review was to investigate structural neuroplasticity following MBIs. Methods: Following PRISMA-ScR guidelines, databases were searched for studies published between 2010 and 2023 that used structural MRI to assess structural brain changes in subjects after receiving MBIs. Nine studies met inclusion criteria, including five randomized controlled trials. Results: Mindfulness interventions ranged from 10 h of training to long-term practice spanning decades. Structural changes were most consistently observed in the insula, prefrontal cortex, hippocampus, posterior cingulate, and temporoparietal junction, regions tied to interoception, executive control, and self-referential processing. The greatest structural changes were reported in studies implementing multi-month interventions or long-term meditative practice. Conclusions: MBIs are associated with structural brain changes across a limited and heterogeneous body of literature, but current evidence is insufficient to draw firm conclusions regarding causality or consistency of effect. Larger, diverse, and more methodologically rigorous trials with extended follow-up are needed to clarify the durability and significance of observed changes.