Fig. 4.

Paradoxical effects of the olfactory and intranasal trigeminal systems in chronic PTSD. Greater odor detection impairment was associated with increased burned rubber (BR) odor-elicited activation in right 1° somatosensory cortex (SsCtx) in combat veterans with PTSD (CV+PTSD), but not healthy combat veterans (CV-PTSD) (top scatter plot). In contrast, greater odor threat “sensitivity” (BR intensity ratings) in CV+PTSD, but not CV-PTSD, was associated with less BR odor-elicited activity in right primary olfactory (anterior piriform) cortex (APCtx) (bottom scatter plot).