Two distinct mental strategies used to manage pain—focusing attention externally and re-appraising the pain—involve different brain pathways, according to new research using functional magnetic resonance imaging (fMRI). The study appeared in the journal Anesthesiology (2011, 115 , 844–51).
Investigators from Stanford University in Palo Alto, California, wanted to determine whether distinct methods of pain management impacted the same neural pathways. The researchers tested subjects with chronic pain under two separate conditions. For the first analysis, subjects used “external focus of attention” to manage pain by drawing their attention away from their pain and focusing on something else. MRI data showed activity in cortical areas, which are responsible for higher brain functions. In the second condition, study subjects were told to use “re-appraisal”—changing the interpretation of pain from threatening to nonthreatening. For example, a subject re-appraises a situation when he reassures himself that his pain is bearable and he won’t let it stop him from functioning. MRI data for this mental strategy showed activity in deep brain structures, which are related to emotional behavior, and in some cortical regions.
Senior study author Sean C. Mackey, MD, PhD, chief of the division of pain management at Stanford University, said, “Our study helped support that each cognitive strategy may have a unique brain pattern distinct from other strategies.”
Mackey and colleagues believed that their finding might explain why some strategies are more effective for certain patients than others. Limitations of the study were that subjects did not necessarily represent all individuals who suffer from chronic pain and that the sample size was small. More research was recommended.