Nine individuals in each group were indicated in the neuroimaging analysis, this should be indicated in the abstract.
However, the authors need to compare their findings to other research evidence showing impaired EIH and/or descending inhibition in patients with FM - especially considering that their results did not support EIH in the controls. The authors merely mention that the exercise stimulus may have been insufficient for the controls to show EIH without critically discussing what such a conclusion would mean (eg, FM patients have better EIH mechanisms than the controls).