Brain Imaging and Pain: Analysis of Placebo Analgesia

This study is a basic science study of the mechanisms of placebo analgesia in asymptomatic healthy individuals. Each participant receives a baseline pain testing session, followed by a conditioning paradigm that results in expectation of pain relief and conditioning. They then undergo functional magnetic resonance imaging during either placebo (conditioned analgesia) or baseline. To examine order effects and habituation, the participants also either undergo a repeated placebo or a repeated baseline. The primary dependent measures in the study are the fMRI determined regions of interest, in a network of brain areas associated with pain processing. The anticipated outcome of the study is the alteration of network connectivity between sensory, affective, evaluative areas of the brain associated with placebo.

Because this is not a traditional clinical trial, there are not traditional efficacy criteria, rather the outcomes are changes in brain function from manipulations of patient expectation and classical conditioning.