MS PATHS Normative Sub-Study

Key Inclusion Criteria * Ability to understand the purpose and risks of the study and provide signed and dated informed consent and authorization to use protected health information in accordance with national and local participant privacy regulations. Key Exclusion Criteria * History of human immunodeficiency virus. * Confirmed or suspected pregnancy. * Diagnosis of migraine requiring medication or any other participant-reported diagnosis of a neurological disease or condition (e.g., stroke, transient ischemic attack, epilepsy, brain infection, brain surgery, prior head injury or concussion, or brain tumor). * Any participant-reported diagnosis of an autoimmune disorder (e.g., rheumatoid arthritis, Sjögren's syndrome, scleroderma, or systemic lupus erythematosus). * Standard MRI exclusion criteria, including claustrophobia, inability to lay still in the magnet (e.g., tremor), or any type of implanted metal in the body that would be affected by the strong magnetic field. NOTE: Other protocol defined Inclusion/Exclusion criteria may apply