Apkarian AV. Pain perception in relation to emotional learning. Curr Opin Neurobiol. 2008 Aug;18(4):464-8. Noninvasive brain imaging has established the participation of the cortex in pain perception and identified a long list of brain structures involved. More recent studies show the interaction between clinical chronic pain conditions and the reorganization of the brain functionally, anatomically, and chemically. Mechanisms underlying this...