It is well-established that the practice of mindfulness meditation leads to improved emotion regulation as well as to changes in brain structure, but relatively little is known about the relationship between these changes. Brain regions found to be impacted by mindfulness training include the ventromedial prefrontal cortex, the hippocampus, and the amygdala. Interestingly, there is evidence that these brain structures are part of a brain circuit that is critical for both the extinction of conditioned fear responses and for the retention of fear extinction memory. Evidence exists that the integrity of the axonal pathway between the amygdala and the vmPFC is crucial for the successful regulation of emotions. The proposed study will test whether mindfulness meditation practice strengthens structural connections between the vmPFC and the amygdala, using diffusion tensor imaging. Furthermore, it will investigate whether these potential changes in structural connectivity are related to an improvement in fear extinction learning.