Several limitations should be considered with regard to interpreting the study findings. The data sample acquired in this study was moderate in size (15 per study group) which limits the generalizability of the study findings. In addition, fMRI data in this study was acquired for whole brain, and these findings were reported as exploratory analyses, however, the main results reported here are focused on specific cortical regions, hypothesized a priori to be associated with the challenge paradigms. The regions chosen, the cingulate gyrus and amygdala, are known to be sensitive to susceptibility artifact. This type of artifact makes it difficult to interpret null or negative results, as the absence of a significant difference between study conditions may either reflect the true state or be due to signal loss. Given the fact that we observed significant differences in both cingulate and amygdalar responses to both masked affective stimuli types between groups, the question of signal distortion possibly resulting in null effects is not likely. Further, regions of interest used in the current study were based on the use of an atlas
