Do Olfactory Stimuli Increase Presence During Exposure Tasks: A Comparative Study

Exposure therapy (ET) is an extensively studied and supported treatment for anxiety and trauma-related disorders. ET works by exposing the patient to the feared object or situation without any danger in order to overcome the related anxiety. Over the past few years, various technologies including head-mounted displays (HMDs), scent machines, and headphones have been used to augment the exposure therapy process by presenting multi-sensory cues (e.g., sights, smells, sounds) to increase the patient*s sense of presence. While studies have shown that scents can elicit emotionally charged memories, no prior research could be identified that examined the effect of olfactory stimuli upon the patient*s sense of presence during exposure tasks. In this study, the effect of olfactory stimuli on subject*s sense of presence was assessed via psychophysiological response (electrodermal activity), visual scanning, and self-report measures. Linear Mixed Modeling showed relationships between olfactory stimuli and presence ratings as well as self-reported anxiety levels, but not visual scanning or physiological arousal. Recommendations were made for continued research in the union of olfactory stimuli, presence, and exposure therapy