The Warmth, Anticipation, Sensation, Aversion, and Body-part Imaging Study

This is a brain imaging (fMRI) research study that explores how healthy volunteers experience warmth and mild pain sensations. It is not testing a treatment — it is looking at brain activity patterns to better understand pain perception. **You may be eligible if...** - You are a healthy volunteer aged 18 or older - You can read and speak English - You have no current or recent history of chronic pain - You have abstained from alcohol and recreational drugs for 48 hours before the scan - You pass all MRI safety screening checks - If female, you are not pregnant and are using reliable contraception **You may NOT be eligible if...** - You have any metal in your body (implants, pacemaker, shrapnel) or history of working with metal fragments - You are claustrophobic - You have a history of cancer, stroke, seizures, neurological conditions, or cardiovascular disease - You have chronic pain, chronic fatigue, or a history of substance abuse - You have an autoimmune or inflammatory condition - You have a current or recent history of psychiatric illness Talk to your doctor to see if this trial is right for you.