This study explores how **pulsed tVNS** (transcutaneous vagus nerve stimulation) can help in learning tasks. *Vagus nerve* is a nerve that helps control certain functions in the body. The study tests if short bursts of stimulation can improve learning by giving feedback when actions are performed. Participants will attend three sessions. The first is an eye-tracking session to see how their pupils react to the stimulation. If they respond well, they're invited for two more sessions to see if the stimulation helps in learning tasks while in an fMRI scanner (a machine that makes detailed images of the body). The task involves choosing actions that lead to rewards based on cues. The study will see if high-intensity stimulation during this task can improve learning.

• Study involves three sessions.
• Participants perform learning tasks during stimulation.
• Participants must be aged 18-35 and meet certain health criteria.