Olfactory stimuli increase presence during simulated exposure

Abstract

Exposure therapy (EXP) is an extensively studied and supported treatment for anxiety and trauma-related disorders. EXP works by exposing the patient to the feared object or situation in the absence of danger in order to overcome the related anxiety. 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. Studies have shown that scents can elicit emotionally charged memories, but no prior research could be identified that examined the effect of olfactory stimuli upon the patient’s sense of presence during simulated exposure tasks. Methods: 60 adult participants navigated a mildly anxiety-producing virtual environment (VE) similar to those used in the treatment of anxiety disorders. Participants were screened for olfactory dysfunction and history of seizures. Participants completed questionnaires pertaining to their (a) tendency to immerse themselves in activities and (b) current health. Visual exploration and presence ratings were collected throughout the experiment. Results: Linear Mixed Modeling showed statistically significant relationships between olfactory stimuli and presence as assessed by both the In group Presence Questionnaire (IPQ: R2 =.85, (F(3,52) = 6.625, p =.0007) and a single item visual-analogue scale (R2 = .85, (F(3,52) = 5.382, p = .0027).