Furthermore, participants must not suffer from a mental illness, including Attention Deficit Hyperactivity Disorder (ADHD), and must not have a recent history of drug abuse. Additionally, participants must also be right-handed, not suffer from a fear of small, enclosed spaces (claustrophobia), and not have any implanted medical devices such as a pacemaker, orthodontic braces, or shrapnel. They must not have a history of seizures, uncontrolled hypertension or known renal impairment.