As I recall, there were a couple fMRIs that participants had as part of the study protocol. I wonder if a second study from Baraniuk's team will be forthcoming more specific to the fMRI results. START appears to be simply POTS triggered by exercise - did any CFS subjects satisfy START requirements? Since we seem to share the same CSF values as controls, could what he be demonstrating is a new metric for at least a form of PEM (maybe two)? Afterall, the differences appear to have been triggered by exertion/exercise.