Neuroimaging of Opioids and Pain Interactions

Principal Investigator: Charles S. Cleeland, Ph.D.

The purpose of this study is to examine the interaction between morphine, positive imagery and pain as measured by functional magnetic resonance imaging (fMRI) in healthy volunteers. We hope to determine the sites of activation in the brain that are associated with pain and the analgesic action of morphine and positive imagery.

Specific Goals

  • To measure the changes in blood flow that occur in the brain during the presentation of an experimental pain stimulus (Complete)
  • To determine how these changes in blood flow are affected by the use of either morphine or positive imagery to decrease the pain (Complete)



In this study, we are using the pressure algometer and the cold pressor to induce pain in human volunteers. To experience pain using the pressure algometer, the volunteer places his or her index finger in a plexiglass apparatus and a weight is placed on top of it. To experience pain using the cold pressor technique, the volunteer places his or her hand in ice water.


This is a two-day study. On each day the volunteer has an fMRI while he or she experiences pain. On one day, the volunteer receives morphine as a treatment for pain, and on the other day the volunteer receives positive imagery suggestions as a treatment for pain.


The intensity and unpleasantness of pain are measured separately using 0-10 self-report scales. Brain activation is measured by the changes in blood flow observed in fMRI scans.

For more information

Contact Guadalupe Palos, Dr.P.H., at