The aim of this project is to determine whether the acute oral administration of Ibuprofen changes the activation pattern in the amygdala and other brain structures during functional magnetic resonance imaging. The investigators use a double-blind, randomized, repeated-measures design. Each of the 20 healthy control subjects will be tested three times and receive placebo, 200 mg or 600 mg dose of ibuprofen p.o. The study will consist of 4 sessions: a baseline screening session and 3 testing sessions scheduled 1-2 weeks apart. Each of these individuals will undergo a multi-level assessment based on the RDoC approach that consists of (a) a standardized diagnostic assessment, (b) self-report questionnaires assessing the positive and negative valence domains as well as interoception, (c) behavioral tasks assessing reward-related processing, avoidance, and aversive processing, cognition, and interoception; (d) physiological measurements consisting of facial emotion expression monitoring, heart rate and respiration, (e) functional magnetic resonance imaging focusing on reward-related processing, fear conditioning and extinction, cognitive inhibition, and interoceptive processing, and (f) biomarker assessments.