**Pulsed tVNS Protocol and Reinforcement Learning Study** This study explores how a special kind of brain stimulation called **taVNS** (transcutaneous auricular Vagus Nerve Stimulation) might help people learn better. The vagus nerve is a part of your body that sends signals from your brain to other parts. In the study, participants will receive short bursts of this stimulation to see how it affects learning actions and outcomes. - **Participation involves three sessions**, including eye-tracking and two neuroimaging sessions to test brain responses. - **Stimulation is safe and non-invasive**, with intensity adjusted to a mild pricking sensation, ensuring comfort. - **Eligibility:** You must be 18-35 years old, with a Body-Mass-Index (BMI) of 18.5 to 30, and have normal or corrected vision to join. Participants will undergo activities that test learning by choosing actions that could lead to rewards, all while receiving different levels of stimulation. The study aims to determine the best time to give stimulation during learning and if it helps improve decision-making skills.