Research News

New faculty: Todd Monroe explores how neurobiology can better guide pain management

Todd Monroe, assistant professor of nursing (Susan Urmy/Vanderbilt)

When Todd Monroe’s grandmother was diagnosed with breast cancer late in the course
of her dementia, the nursing home staff caring for her struggled to assess her pain.

Even after she was moved to hospice care, many of the nurses were reluctant to administer pain medications to someone who could no longer speak. Fortunately, Monroe was with his grandmother at the time of her death from end-stage Alzheimer’s disease to personally ensure that she received the medications she needed. But the experience made him realize that many people don’t have family members who are medically trained and can advocate on their behalf.

Monroe, assistant professor of nursing, has focused his research on showing how the neurobiology of pain can be used to better guide pain management in older adults with and without dementia. He was initially drawn to Vanderbilt for his post-doctoral work because the School of Nursing, Vanderbilt University Institute of Imaging Science and the Psychiatric Neuroimaging Program combined to offer a multidisciplinary, collaborative training opportunity. Professor of Nursing Lorraine Mion and VUIIS Director John Gore in particular have served as mentors.

With financial support from the John Hartford Foundation and the Atlantic Philanthropies, the Mayday Fund, and the Vanderbilt Institute for Clinical and Translational Research, Monroe is examining how healthy older adults and older adults with mild to moderate Alzheimer’s disease experience and process experimental pain. The research uses a combination of psychophysical (verbal reports) and functional magnetic resonance imaging to examine brain regions responsible for the sensory and emotional responses to pain. An FDA-approved experimental thermal pain device is used to administer different levels of stimuli. The subject first provides a verbal pain rating, and then brain responses to the thermal stimuli are recorded using fMRI.

“[rquote]A key point is that the response to experimental acute thermal pain has been shown to predict chronic pain states outside of the laboratory,” Monroe said.[/rquote]

Working closely with Ronald Cowan, director of the Vanderbilt Psychiatric Neuroimaging Program, Monroe found that older women seem to find pain less unpleasant when compared to older men.

“We theorize that more lifetime chronic pain exposure may alter the neurobiology in females,” Monroe said. “While finding pain to be less unpleasant may seem attractive, we believe this phenomenon may lead to under-reporting and under-treatment of pain in older females. To our knowledge, this will be the first study to report psychophysical and neurophysiological sex differences in pain in older adults.

“Simultaneously, we are examining alterations in pain processing in the brains of people with dementia,” he said. “This work is important because communication problems in dementia may predispose to difficulties in reporting pain.”

View the complete list of new university faculty for 2013-14.

View the complete list of new medical faculty for 2013.