Functional Neuroimaging to Detect the Neural Signatures of the Unpleasantness of Pain and Effort
Background: The way the brain processes rewards and punishments may play a role in some disorders of the nervous system. People with chronic overlapping pain conditions (such as myalgic encephalomyelitis/chronic fatigue syndrome \[ME/CFS\]) may have heightened responses to unpleasant, punishing sensations. Some of these conditions may also cause heightened responses to effort; this is an unpleasant sensation felt during physical and mental exertion.
Objective: To learn more about how the brain processes different unpleasant sensations.
Eligibility: People aged 18 to 50 years with ME/CFS. Healthy volunteers are also needed.
Design: Participants will have 3 visits in 1 to 5 weeks. Visit 1: Participants may have a neurologic exam. They will have a mock magnetic resonance imaging (MRI) scan. They will lie on a bed in a wooden tube while they practice 2 tasks: Thermal pain rating: A device that creates mild to moderate heat will be placed on one leg. Physical effort rating: Participants will squeeze a plastic bar with different levels of force. Visit 2: Participants will have a real MRI scan. They will lie on a table that slides into a large tube. Visit 3: Participants will have another MRI scan. They will repeat the thermal pain and physical effort tasks while in the scanner. Sensors will be placed on 1 arm to measure how the muscles function as they squeeze the bar. Their heart rate will be tested: They will hold their finger against a camera lens for 1 minute. They will do 2 other tasks: 1 requires repeatedly pressing a key on a keyboard, and the other requires squeezing a bar.
⁃ Healthy Controls: In order to be eligible to participate in this study as a healthy control, an individual must meet all the following criteria:
• Ability of subject to understand and the willingness to sign a written informed consent document.
• Stated willingness to comply with all study procedures and availability for the duration of the study.
• Male or female, aged 18-50 (inclusive).
• Good general health as evidenced by medical history and/or physical examination.
⁃ ME/CFS Patients: In order to be eligible to participate in this study as an ME/CFS patient, an individual must meet all the following criteria:
• Ability of subject to understand and the willingness to sign a written informed consent document.
• Stated willingness to comply with all study procedures and availability for the duration of the study.
• Male or female, aged 18-50 (inclusive).
• Has a diagnosis of ME/CFS, meeting at least one of three ME/CFS criteria: the 1994 Fukuda Criteria, the 2003 Canadian Consensus Criteria for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome, or the Institute of Medicine Diagnostic Criteria.