‘Placebo effect’ region in brain mapped by fMRI

Researchers at Northwestern University and the Rehabilitation Institute of Chicago (RIC) say functional MRI (fMRI) helped derive a brain-based marker predicting the “placebo effect,” potentially leading to treatment plans accounting for patients with high positive responses to placebos.

The study, published in PLOS Biology, developed fMRI technology with “the potential to usher in an era of individualized pain therapy by enabling targeted pain medication based on how an individual’s brain responds to a drug.”

According to a press release from Northwestern, the research discovered a unique brain region within the mid frontal gyrus that identifies placebo pill responders in one trial and can be validated (95 percent correct) in the placebo group of a second trial.

Beyond clinical applications, it could help in trials by screening out patients with high placebo responses.

“Given the enormous societal toll of chronic pain, being able to predict placebo responders in a chronic pain population could both help the design of personalized medicine and enhance the success of clinical trials,” Marwan Baliki, PhD, research scientist at RIC and an assistant professor of physical medicine and rehabilitation at Northwestern University Feinberg School of Medicine, said in a statement.

More than half the participants reported significant pain relief from ingesting a placebo pill. Baliki and his coauthor said future studies could “eventually provide a brain-based predictive best-therapy option for individual patients”, potentially decreasing unnecessary use of ineffective, expensive treatments or opioid painkillers by patients.