MBSR Mechanisms in GAD

Mindfulness-Based Stress Reduction (MBSR) has demonstrated efficacy for Generalized Anxiety Disorder (GAD), yet there remains a major knowledge gap about its neural mechanisms. This study will examine functional activation of brain regions associated with the fear extinction network (ventromedial prefrontal cortex (vmPFC), hippocampus, and amygdala) as a specific probe of the 'instinctual' type of emotion regulation as well as large-scale functional connectivity as a marker of neural plasticity changes. Sex differences in MBSR-induced neural changes and their relationship to sex differences in clinical GAD response will be examined. Finally, a novel statistical approach will be used to explore whether baseline neural measures can predict neural changes and clinical symptom reduction to identify likely MBSR responders. The unique combination of a focus on GAD, an anxiety condition with established emotion regulation difficulties implicating target neural circuits, previously demonstrated MBSR efficacy, and sex differences with rigorous fMRI behavioral probes with novel analytic approaches ought to provide major new insights about MBSR versus stress education mechanisms and sex considerations, moving towards precision medicine that could guide future treatment development research. Eligible participants with Generalized Anxiety Disorder will be 2:1 randomized to group intervention with MBSR or stress education classes. They will participate for 13-14 weeks plus one 3 month follow up assessment (23-24 weeks from screening). Full participation includes screening, baseline, endpoint and 3 month follow up assessments, two sets of experimental days 12 weeks apart which include fMRI scans, and 8 weeks of the assigned group intervention (either MBSR or stress education).