Increased activation in the PFC has been correlated with chronic pain.[3] In a study comparing the MRI scans of chronic lower back pain patients before and after treatment to their healthy counterparts, patients with chronic pain exhibited thinner PFCs than the control.[3] After treatment, chronic lower back patients showed increased thickness in the PFC which decreased pain perception and physical disability.[3] Additional brain regions are involved in pain perception in what is referred to as the 'pain matrix'.[1] The pain matrix includes the primary somatosensory cortex (SI), insula, ACC, and thalamus.[1] Reduction of pain perception via mediation is mediated by the interconnected brain pathways between pain perception and meditation. These intersections are what contribute to the reduction in perceived pain via mediation.