CLB’s recent conference on Pain and Neuroimaging has been featured in this week’s edition of Science. 323 Science 195 (2009). In Brain Scans of Pain Raise Questions for the Law, Greg Miller highlights the December 4th conference at Stanford Law School where Sean Mackey, Adam Kolber, Amanda Pustilnik, Katja Wiech, Vania Apkarian, Stephen Easton, David Faigman, and our own Hank Greely commented on the legal uses of neuroimaging as evidence of pain.
Each of the speakers raised significant near-term challenges to the use of fMRI in legal proceedings as evidence of pain. However, some of the speakers thought the horizon was not that far off for its appropriate legal use.
Katja Wiech underscored the significant variability in our subjective assessment and sensitivity to pain. She also presented interesting data from her lab on the effect of perceived self-control on pain assessments. Interestingly, pain intensity was rated as significantly higher to the subjects when they were told that a computer or other person controlled the stimulation, even though the stimuli strength was the same throughout. This research may be helpful in developing more humane policies for implementing painful procedures in the clinic or in the criminal justice system.
Sean Mackey questioned how we might ever be able to use brain imaging to make reverse inferences about whether someone is or is not in pain. Put differently, just because we see brain activation in a plaintiff, it does not mean we can currently say she was or was not in pain. This is because there are no specific “pain centers” of the brain that are common to all people and across all pain stimuli.
Vania Apkarian discussed the behavioral effects of chronic pain. According to data he presented, chronic back pain patients are impaired at emotional learning, but have increased sensitivity to taste. He therefore quipped, “take them to Napa rather than Vegas.” Based on characteristic activation in certain brain areas, Vania’s team could predict how long someone had been in pain based on the magnitude of the activation in an area of the brain called the right insula. The more time the person has been in a specific kind of pain, the more active this area is. This could have interesting legal significance, as it might one day be used as a time marker to help identify the cause of a particular injury. However, this technique should not be admissible until we know more about the particular type of pain stimulus and how specific the brain activation is in response. What is the predictive value of the brain imaging when cross-referenced with the subject’s actual time-course of pain? This may be too difficult to isolate in a way that would be useful for a particular plaintiff, still, it’s interesting…
Unfortunately I was not able to attend all of the fascinating conference. If you were there and had any other points you either heard or wanted to share, please do so here!
If you would like to listen to the audiofeed from the conference, you can download the files here.