PROJECT SUMMARY Chronic pain affects approximately 20% of both adults and children in the US and is a source of substantial disability and health care costs. Chronic pain can be challenging to diagnose due to the presence of poorly understood symptoms. When diagnosed, current pharmacologic treatments for pain are remarkably ineffective, while effective non-pharmacologic treatments remain under-utilized. These shortcomings in the diagnosis and treatment of pain arise from tremendous gaps in our knowledge about the basic central nervous system systems that process nociceptive information and instantiate an experience of pain. These gaps are further amplified in the case of pediatric chronic pain due to a lack of basic/translational research. Our team of basic scientists and clinician scientists is uniquely positioned to perform human pediatric studies integrating functional neuroimaging with quantitative sensory testing and psychological assessments to delineate brain systems engaged during chronic pain. We will examine four distinct chronic pain syndromes: migraine, complex regional pain syndrome, functional abdominal pain, and musculoskeletal pain. We seek to 1) Identify shared and distinct brain systems engaged by different forms of pediatric chronic pain, 2) Determine if predictors of recovery differ across different chronic pain conditions, 3) Delineate brain systems associated with the spread of pain. We will follow patients longitudinally for 1 year after initiation of treatment to assess the degree of recovery and spread of pain. This study will provide a critical foundation of basic knowledge for future clinical trials of diagnostic markers for different forms of chronic pain and for the development of new treatments for chronic pain.