Acceptance and Commitment Training for Adolescents and Young Adults With Neurofibromatosis Type 1, Plexiform Neurofibromas, and Chronic Pain

Background: \- People with neurofibromatosis type I (NF1) and plexiform neurofibroma (PN) tumors often have chronic pain that his hard to control. People usually take medicines for the pain, but they may not work well and might cause side effects. A new strategy called Acceptance and Commitment Training (ACT) may help these people cope with chronic pain. ACT focuses on things like values and living in the moment. Objective: \- To see if Acceptance and Commitment Training improves pain coping in people with NF1 pain. Eligibility: \- People age 16-34 who have NF1, 1 or more PN tumors, and pain that interferes with their daily functioning. Design: * Participants will be screened with a physical exam, medical history, and questions about their pain. * Participants will fill out questionnaires about their pain and feelings. Their heart rate will be measured via electrocardiogram (ECG). * Participants will be divided into 2 groups randomly. One will wait 8 weeks. * The other will start training right away. * Participants will have 2 two-hour sessions with an ACT trainer. They will learn techniques for setting goals based on personal values and other ways to cope with pain. They will get a workbook and a compact disc (CD) to take home for practice. * Participants will do practice exercises at home between sessions. They will get weekly emails with a practice exercise. They will join video chat sessions via home computer with their trainer. * All participants will return to National Institutes of Health (NIH) after 8 weeks for questionnaires and an ECG. The wait group will then start training. They will return 8 weeks later for questionnaires and an ECG. * Six months later, they will complete questionnaires from home by computer.