ABSTRACT
Stress- and trauma-related disorders, including posttraumatic stress disorder (PTSD), are characterized by an increased sensitivity to threat cues. Given that threat detection is a critical function of olfaction and that combat trauma is commonly associated with burning odors, we sought a better understanding of general olfactory function as well as response to specific trauma-related (i.e. burning) odors in combat-related PTSD. Trauma-exposed combat veterans with (N = 22) and without (N = 25) PTSD were assessed for general and specific odor sensitivities using a variety of tools. Both groups had similar general odor detection thresholds. However, the combat veterans with PTSD, compared to combat veterans with comparable trauma exposure, but without PTSD, had increased ratings of odor intensity, negative valence, and odor-triggered PTSD symptoms, along with a blunted heart rate in response to burning rubber odor. These findings are discussed within the context of healthy versus pathological changes in olfactory processing that occur over time after psychological trauma.
ABSTRACT
Cue-elicited reactivity is a significant factor in relapse during smoking quit attempts. Previous research has focused primarily on visual smoking cues, with very limited research examining reactivity to olfactory triggers. Twenty-six adult non-treatment-seeking, nicotine-dependent smokers were exposed to 7 odorants during a cue-reactivity session measuring heart rate, skin conductance, and subjective craving. Cues included 2 cigarette odors (fresh tobacco and cigarette smoke), 2 odors previously identified as smoking-related (freshly mowed grass and coffee), 2 odors previously identified as unrelated to smoking (lavender and burned rubber), and 1 odorless control (propylene glycol). Pairwise comparisons demonstrated that subjective intensity of craving was significantly higher following exposure to the fresh tobacco odor compared with the odorless control (p < .01). A significant main effect for cue type on a physiological measure of arousal was also revealed, with a fresh tobacco odor-elicited significant increase in skin conductance level compared with the odorless control. However, no main effect of cue type on heart rate was found (p = .25). The results of the present study indicate that cigarette odor is an effective olfactory cue that heightens both subjective craving and increases skin conductance in smokers. Future research is needed to evaluate whether avoidance of these odors, or extinction of responses to them, can reduce relapse risk during smoking quit attempts.
