Chronic pain is a debilitating condition, and opioid medications are commonly used to manage it. However, their effects on the brain are still not fully understood. Your participation can help change that!

Opioids are prescription medications used to treat pain. Common prescription opioids include hydrocodone, Vicodin, Percocet, Fentanyl, Duragesic, OxyContin, oxycodone, and morphine. Individuals on methadone, tramadol, or codeine are not eligible for this study.

An MRI is a type of scan that uses strong magnets and radio waves to create detailed pictures of the brain. This procedure is non-invasive, with no injections involved in this study. 

The MRI scanner is a large, cylindrical machine with an opening in the center. MRI scans are performed by skilled technologists at the Stanford Richard M. Lucas Center for Imaging, located at 1201 Welch Rd, Stanford, CA 94305.

Before your scan, you will change into scrubs and be screened for metallic objects. Then, you will lie down on a narrow table that will move into the scanner. This is a brain MRI scan with a head coil placed around your head. To protect your ears from the loud noises made by the scanner, you will be provided with earplugs. The scan itself will take about one hour. During the scan, you can either relax with your eyes closed (but try not to fall asleep), look at a cross on a screen when it appears, or play a simple game that you will practice before the scan.

After the scan, you can resume normal activities immediately.

We use heat and cold to understand how your nerves process pain. For the heat test, a small device is placed on your skin that gradually warms up, allowing us to see how you feel and react to increasing temperatures. In the cold test, you put your hand in ice-cold water to measure how much cold you can handle before it becomes painful. You will complete these tests at the Stanford Division of Pain Medicine research lab, located at 1070 Arastradero Rd, Suite 200, Palo Alto, CA 94304.

The cognitive tests include one you will complete at home on your computer, and another on an iPad in the lab. These tests assess your memory, attention, and decision-making skills. You will also answer questions about your pain, health, and daily activities.