A Brain Imaging Study With Positron Emission Tomography and the Radiotracer [11C]UCB-J to Estimate How Fast Brivaracetam and Levetiracetam Enter the Brain in Healthy Volunteers

Inclusion Criteria: Inclusion Criteria: * Subject is male or female and between 18 to 55 years of age (inclusive) * Subject is in good physical and mental health, in the opinion of the Investigator, determined on the basis of medical history, physical and neurological examinations, vital signs, 12-lead Electrocardiography (ECG), and clinical laboratory tests * Female subjects of childbearing potential must have a negative pregnancy test; female subjects of childbearing potential have to confirm that, for 1 month prior to the first administration of the study medication and during the entire study until the Safety Follow-Up (SFU) Visit she will either use a highly effective contraceptive method (eg, oral contraception, intrauterine device, diaphragm with spermicide) or abstain from sexual activity that can cause pregnancy Exclusion Criteria: Exclusion Criteria: * History or presence of clinically significant respiratory, gastrointestinal, renal, hepatic, pancreatic, hematological, cardiovascular, musculoskeletal, genitourinary, immunological, or dermatological disorders, or any type of cancer * Subject has a history of a neurological diagnosis, including but not limited to stroke, traumatic brain injury, epilepsy, space occupying lesions, multiple sclerosis, Parkinson's disease, vascular dementia, transient ischemic attack, or any other neurological disorder that may influence the outcome or analysis of the scan results * History of donation of more than 450 mL of blood within 60 days prior to dosing in the Yale PET center or planned donation before 30 days has elapsed since intake of study drug * The subject has Magnetic Resonance Imaging -incompatible (MRI - incompatible) implants and other contraindications for MRI, such as a pacemaker, artificial joints, non-removable body piercings, etc. * Subjects who have received a diagnostic or therapeutic radiopharmaceutical less than 7 days prior to participation in this study * Participation in other recent research studies \< 1 month or \< 1 year for studies involving ionizing radiation that would cause the subject to exceed the yearly dose limits for healthy volunteers